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    Double oops. Yes, BVDss is exactly what I thought: Vdrain - Vsource.
    Beyond this there is conduction, right? For this particular part
    this happens in an "all at once" fashion and the heat is spread
    evenly so it takes a relatively large, sustained current to risk
    damaging the chip, right?<br>
    So if the body diode has avalanched it's close to a short circuit
    and so the current goes like this:<br>
    <br>
    <pre>        +V <<----|</pre>
    <pre>        coil     |</pre>
    <pre>        source   |</pre>
    <pre>        drain    |</pre>
    <pre>        ground >>|
</pre>
    Now the body diode is a snubber/freewheeler/<insert five other
    synonyms>. If the supply voltage, inductance, turn off time ,
    transistor selection are all OK then an external diode is a waste of
    money.<br>
    <br>
    What am I missing here?<br>
    <br>
    -Pete<br>
    <br>
    <div class="moz-cite-prefix">On 03/11/2016 04:31 PM,
      <a class="moz-txt-link-abbreviated" href="mailto:kschilf@yahoo.com">kschilf@yahoo.com</a> wrote:<br>
    </div>
    <blockquote
      cite="mid:1341997360.534201.1457731919214.JavaMail.yahoo@mail.yahoo.com"
      type="cite">
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                          id="yiv0647688466yui_3_16_0_1_1457730728150_2606"
                          style="color:#000;background-color:#fff;font-family:HelveticaNeue,
                          Helvetica Neue, Helvetica, Arial, Lucida
                          Grande, sans-serif;font-size:16px;">
                          <div id="yiv0647688466">
                            <div
                              id="yiv0647688466yui_3_16_0_1_1457730136768_3125">
                              <div
                                id="yiv0647688466yui_3_16_0_1_1457730136768_3124"
                                style="color:#000;background-color:#fff;font-family:HelveticaNeue,
                                Helvetica Neue, Helvetica, Arial, Lucida
                                Grande, sans-serif;font-size:16px;">
                                <div
                                  id="yiv0647688466yui_3_16_0_1_1457729256661_8666">Hi
                                  Pete,</div>
                                <div
                                  id="yiv0647688466yui_3_16_0_1_1457730136768_3126"><br
                                    clear="none">
                                </div>
                                <div
                                  id="yiv0647688466yui_3_16_0_1_1457730136768_3127">
                                  <div
                                    id="yiv0647688466yui_3_16_0_1_1457730136768_3904">The
                                    voltage at each of the three
                                    terminals of the transistor (gate,
                                    drain, source) is a function of the
                                    rest of the circuit.  You can bias
                                    (set voltages, and draw currents)
                                    the transistor anyway you want, once
                                    you understand its behavior (and
                                    limits) at whatever operating point
                                    you set.</div>
                                  <div
                                    id="yiv0647688466yui_3_16_0_1_1457730728150_2705"><br
                                      clear="none">
                                  </div>
                                  <div
                                    id="yiv0647688466yui_3_16_0_1_1457730728150_2701">
                                    <div
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_2610">It
                                      is possible to bias the source
                                      such that Vsource > Vdrain (Vds
                                      < 0).</div>
                                    <div
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_2611">BVDss
                                      the maximum voltage difference
                                      (Vdrain - Vsource) exerted before
                                      you possibly damage the part. 
                                      This value is temperature
                                      dependent.<br clear="none">
                                    </div>
                                  </div>
                                  <div
                                    id="yiv0647688466yui_3_16_0_1_1457730728150_2605"><br
                                      clear="none">
                                  </div>
                                  <div dir="ltr"
                                    id="yiv0647688466yui_3_16_0_1_1457731473767_2612">
                                    <div dir="ltr"
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_4229">Born
                                      before Wikipedia, I still believe
                                      in books.  :-)</div>
                                    <div dir="ltr"
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_7101"><br
                                        clear="none">
                                    </div>
                                    <div dir="ltr"
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_7100">Since
                                      textbooks ain't cheap, borrow a
                                      sophomore level circuits text
                                      (NCSU library, etc.).  Peruse the
                                      chapter on BJT's and MOSFET's. 
                                      That should clear up some of the
                                      mystery.  :-)</div>
                                    <div dir="ltr"
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_12052"><br
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                                    </div>
                                    <div dir="ltr"
                                      id="yiv0647688466yui_3_16_0_1_1457731473767_12054">
                                      <div
                                        id="yui_3_16_0_1_1457732229592_2683">Don't
                                        let the smoke out (at least
                                        while anybody is looking!)  :-)</div>
                                      <div
                                        id="yui_3_16_0_1_1457732229592_3044"><br>
                                      </div>
                                      <div
                                        id="yui_3_16_0_1_1457732229592_3045">Sincerely,<br>
                                      </div>
                                    </div>
                                  </div>
                                  <div
                                    id="yiv0647688466yui_3_16_0_1_1457731473767_12072">Kevin
                                    Schilf</div>
                                </div>
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id="yiv0647688466yui_3_16_0_1_1457729256661_8404"><br clear="none">
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                              Grande, sans-serif;font-size:16px;">
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                                id="yiv0647688466yui_3_16_0_1_1457729256661_8326"
                                style="font-family:HelveticaNeue,
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                                Grande, sans-serif;font-size:16px;">
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id="yiv0647688466yui_3_16_0_1_1457730136768_3129"><br clear="none">
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                                <div class="yiv0647688466yqt3064303358"
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                                    id="yiv0647688466yqt54586">
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                                      class="yiv0647688466yqt0867570876"
                                      id="yiv0647688466yqt19683">
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                                        class="yiv0647688466yqt9061048935"
                                        id="yiv0647688466yqt51373">
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                                          id="yiv0647688466yui_3_16_0_1_1457729256661_8325">
                                          <font face="Arial" size="2"> </font>
                                          <hr size="1"> <b><span
                                              style="font-weight:bold;">From:</span></b>
                                          Pete Soper via TriEmbed
                                          <a class="moz-txt-link-rfc2396E" href="mailto:triembed@triembed.org"><triembed@triembed.org></a><br
                                            clear="none">
                                          <b><span
                                              style="font-weight:bold;">To:</span></b>
                                          Shane Trent
                                          <a class="moz-txt-link-rfc2396E" href="mailto:shanedtrent@gmail.com"><shanedtrent@gmail.com></a>;
                                          <a class="moz-txt-link-rfc2396E" href="mailto:triembed@triembed.org">"triembed@triembed.org"</a>
                                          <a class="moz-txt-link-rfc2396E" href="mailto:triembed@triembed.org"><triembed@triembed.org></a>
                                          <br clear="none">
                                          <b><span
                                              style="font-weight:bold;">Sent:</span></b>
                                          Friday, March 11, 2016 12:38
                                          PM<br clear="none">
                                          <b
                                            id="yui_3_16_0_1_1457732229592_3084"><span
id="yui_3_16_0_1_1457732229592_3083" style="font-weight:bold;">Subject:</span></b>
                                          Re: [TriEmbed] N-MOSFET Symbol<br
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                                        </div>
                                        <div
                                          class="yiv0647688466y_msg_container"
id="yiv0647688466yui_3_16_0_1_1457729256661_8607"><br clear="none">
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                                            <div
                                              id="yiv0647688466yui_3_16_0_1_1457729256661_8606">
                                              If the transistor shorts
                                              out at 60 volts it's hard
                                              to get the source above 60
                                              volts, right?<br
                                                clear="none">
                                              -Pete<br clear="none">
                                              <br clear="none">
                                              <div
                                                class="yiv0647688466yqt6102815973"
id="yiv0647688466yqt89537">
                                                <div
                                                  class="yiv0647688466moz-cite-prefix"
id="yiv0647688466yui_3_16_0_1_1457729256661_8608">On 03/11/2016 12:36
                                                  PM, Shane Trent wrote:<br
                                                    clear="none">
                                                </div>
                                                <blockquote
                                                  id="yiv0647688466yui_3_16_0_1_1457729256661_8611"
                                                  type="cite">
                                                  <div dir="ltr"
                                                    id="yiv0647688466yui_3_16_0_1_1457729256661_8610">Pete,

                                                    <div
                                                      id="yiv0647688466yui_3_16_0_1_1457729256661_8609"><br
                                                        clear="none">
                                                    </div>
                                                    <div>Sorry,I do not
                                                      understand the
                                                      question. </div>
                                                    <div><br
                                                        clear="none">
                                                    </div>
                                                    <div
                                                      id="yiv0647688466yui_3_16_0_1_1457729256661_8612">Shane</div>
                                                  </div>
                                                  <br clear="none">
                                                  <div
                                                    class="yiv0647688466gmail_quote"
id="yiv0647688466yui_3_16_0_1_1457729256661_8615">
                                                    <div dir="ltr">On
                                                      Fri, Mar 11, 2016
                                                      at 11:50 AM Pete
                                                      Soper <<a
                                                        moz-do-not-send="true"
                                                        rel="nofollow"
                                                        shape="rect"
                                                        ymailto="mailto:pete@soper.us"
                                                        target="_blank"
href="mailto:pete@soper.us"><a class="moz-txt-link-abbreviated" href="mailto:pete@soper.us">pete@soper.us</a></a>> wrote:<br clear="none">
                                                    </div>
                                                    <blockquote
                                                      class="yiv0647688466gmail_quote"
id="yiv0647688466yui_3_16_0_1_1457729256661_8614" style="margin:0 0 0
                                                      .8ex;border-left:1px
                                                      #ccc
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                                                      <div
                                                        id="yiv0647688466yui_3_16_0_1_1457729256661_8613">
                                                        That was very
                                                        clear about the
                                                        other transistor
                                                        forward
                                                        conducting. One
                                                        last question.
                                                        Here's the
                                                        datasheet for
                                                        the transistor
                                                        Brian Grawburg
                                                        started us with:<br
                                                          clear="none">
                                                        <br clear="none">
                                                           <a
                                                          moz-do-not-send="true"
                                                          rel="nofollow"
                                                          shape="rect"
                                                          target="_blank"
href="http://datasheet.octopart.com/FQP30N06L-Fairchild-datasheet-82531.pdf"><a class="moz-txt-link-freetext" href="http://datasheet.octopart.com/FQP30N06L-Fairchild-datasheet-82531.pdf">http://datasheet.octopart.com/FQP30N06L-Fairchild-datasheet-82531.pdf</a></a><br
                                                          clear="none">
                                                        <br clear="none">
                                                        In the context
                                                        of the simple
                                                        case of one of
                                                        these
                                                        transistors
                                                        driving a motor
                                                        what does it
                                                        mean for the
                                                        drain-source
                                                        breakdown
                                                        voltage BVdss to
                                                        be the same as
                                                        the max
                                                        drain-source
                                                        voltage Vdss
                                                        together with
                                                        the avalanche
                                                        current and
                                                        diode recovery
                                                        specs?</div>
                                                      <div><br
                                                          clear="none">
                                                        <br clear="none">
                                                          <br
                                                          clear="none">
                                                        -Pete</div>
                                                      <div><br
                                                          clear="none">
                                                        <br clear="none">
                                                        <br clear="none">
                                                        <div>On
                                                          03/11/2016
                                                          10:40 AM,
                                                          Shane Trent
                                                          wrote:<br
                                                          clear="none">
                                                        </div>
                                                        <blockquote
                                                          type="cite">
                                                          <div dir="ltr">Pete,

                                                          <div><br
                                                          clear="none">
                                                          </div>
                                                          <div>I think
                                                          it is easier
                                                          if you look at
                                                          a half-bridge
                                                          using just two
                                                          transistors
                                                          with a
                                                          bi-polar power
                                                          supply. </div>
                                                          <div><br
                                                          clear="none">
                                                          </div>
                                                          <div>Let's
                                                          assume we have
                                                          +/12V on the
                                                          power rails
                                                          with one
                                                          terminal of
                                                          the motor
                                                          grounded and
                                                          the other
                                                          connected to
                                                          your
                                                          half-bridge
                                                          output. We run
                                                          the motor
                                                          forward by
                                                          turning on the
                                                          top FET and
                                                          applying +12V
                                                          to the motor
                                                          terminal and
                                                          run it
                                                          backward by
                                                          turning on the
                                                          bottom FET and
                                                          applying -12V
                                                          to the motor
                                                          output. In
                                                          this case when
                                                          you cut the
                                                          power to the
                                                          motor the body
                                                          diode of the
                                                          FET that was
                                                          NOT conducting
                                                          acts as the
                                                          catch diode
                                                          for the motor
                                                          (the body
                                                          diode of the
                                                          FET that was
                                                          used to apply
                                                          power does not
                                                          conduct any
                                                          current). So
                                                          if you decide
                                                          to drive the
                                                          motor in only
                                                          one direction
                                                          and remove one
                                                          of the FETs,
                                                          you will have
                                                          to add a catch
                                                          diode since
                                                          you removed
                                                          the body diode
                                                          of the 2nd FET
                                                          which was
                                                          acting as your
                                                          catch diode. <span
style="line-height:1.5;">This is why h-bridge and half-bridge circuits
                                                          with BJTs
                                                          include catch
                                                          diodes and
                                                          ones with
                                                          MOSFET
                                                          typically do
                                                          not.</span><span
style="line-height:1.5;"> </span><span style="line-height:1.5;">I like
                                                          to imaging my
                                                          explanations
                                                          makes sense
                                                          but I am never
                                                          sure. So, did
                                                          that make
                                                          sense to you?</span></div>
                                                          <div><br
                                                          clear="none">
                                                          </div>
                                                          <div>You can
                                                          use external
                                                          catch diodes
                                                          with a MOSFET
                                                          full or
                                                          half-bridge
                                                          but you need
                                                          to ensure the
                                                          external
                                                          diodes have a
                                                          lower Vf than
                                                          the FET body
                                                          diodes to
                                                          ensure the
                                                          external
                                                          diodes conduct
                                                          before the
                                                          body diodes.
                                                          You may also
                                                          see fast
                                                          external
                                                          diodes used
                                                          with a FET to
                                                          clamp
                                                          inductive
                                                          current spikes
                                                          faster than
                                                          the FET body
                                                          diode can
                                                          conduct,
                                                          clamping the
                                                          current spikes
                                                          a lower
                                                          voltage.</div>
                                                          <div><br
                                                          clear="none">
                                                          </div>
                                                          <div>Shane</div>
                                                          </div>
                                                          <br
                                                          clear="none">
                                                          <div
                                                          class="yiv0647688466gmail_quote">
                                                          <div dir="ltr">On
                                                          Thu, Mar 10,
                                                          2016 at 11:51
                                                          PM Pete Soper
                                                          <<a
                                                          moz-do-not-send="true"
                                                          rel="nofollow"
                                                          shape="rect"
                                                          ymailto="mailto:pete@soper.us"
target="_blank" href="mailto:pete@soper.us"><a class="moz-txt-link-abbreviated" href="mailto:pete@soper.us">pete@soper.us</a></a>> wrote:<br
                                                          clear="none">
                                                          </div>
                                                          <blockquote
                                                          class="yiv0647688466gmail_quote"
                                                          style="margin:0
                                                          0 0
                                                          .8ex;border-left:1px
                                                          #ccc
                                                          solid;padding-left:1ex;">
                                                          <div> Out in
                                                          the world
                                                          there are
                                                          droves of H
                                                          bridge motor
                                                          control
                                                          circuits with
                                                          beefy MOSFETS
                                                          and no diodes
                                                          in sight
                                                          except the
                                                          body diodes.
                                                          How is that
                                                          possible?</div>
                                                          <div><br
                                                          clear="none">
                                                          -Pete</div>
                                                          <div><br
                                                          clear="none">
                                                          <div>On
                                                          03/10/2016
                                                          05:59 PM,
                                                          Shane Trent
                                                          wrote:<br
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                                                          </div>
                                                          <blockquote
                                                          type="cite">
                                                          <div dir="ltr">Pete,

                                                          <div><br
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                                                          </div>
                                                          <div>I believe
                                                          you still need
                                                          the snubber
                                                          even with the
                                                          body diode. A
                                                          snubber is
                                                          typically
                                                          placed across
                                                          the inductor
                                                          (motor or
                                                          solenoid or
                                                          relay coil)
                                                          and not across
                                                          the switching
                                                          element. </div>
                                                          <div><br
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                                                          </div>
                                                          <div>For
                                                          example, if
                                                          you turn off
                                                          an N-FET
                                                          supplying
                                                          several amps
                                                          to a large
                                                          solenoid, when
                                                          you turn the
                                                          FET off the
                                                          collapsing
                                                          magnetic field
                                                          of the coil
                                                          will cause the
                                                          voltage across
                                                          the solenoid
                                                          terminals to
                                                          increase. The
                                                          N-FET will
                                                          neither
                                                          forward
                                                          conduct or
                                                          reverse
                                                          conduct via
                                                          the body diode
                                                          until the
                                                          transistors
                                                          breakdown
                                                          voltage (Vds
                                                          max) is
                                                          exceeded and
                                                          the FET
                                                          fails. </div>
                                                          <div><br
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                                                          </div>
                                                          <div>The
                                                          tradeoff with
                                                          using a diode
                                                          snubber (it
                                                          seems to be
                                                          more of a
                                                          voltage clamp)
                                                          across the
                                                          coil is that
                                                          it will act as
                                                          a catch diode
                                                          or
                                                          recirculation
                                                          diode and
                                                          cause the
                                                          solenoid to
                                                          turn off more
                                                          slowly. You
                                                          can strike a
                                                          balance
                                                          between
                                                          voltage and
                                                          turn-off speed
                                                          by combining a
                                                          regular diode
                                                          and Zener
                                                          diode to allow
                                                          the voltage to
                                                          increase
                                                          across the
                                                          solenoid
                                                          without
                                                          exceeding the
                                                          FET's maximum
                                                          voltage
                                                          rating. But
                                                          there are MANY
                                                          ways to design
                                                          inductive
                                                          clamps. </div>
                                                          <div><br
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                                                          </div>
                                                          <div>Shane<br
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                                                          <br
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                                                          <div
                                                          class="yiv0647688466gmail_quote">
                                                          <div dir="ltr">On
                                                          Thu, Mar 10,
                                                          2016 at 4:24
                                                          PM Pete Soper
                                                          via TriEmbed
                                                          <<a
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                                                          rel="nofollow"
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                                                          ymailto="mailto:triembed@triembed.org"
target="_blank" href="mailto:triembed@triembed.org"><a class="moz-txt-link-abbreviated" href="mailto:triembed@triembed.org">triembed@triembed.org</a></a>>


                                                          wrote:<br
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                                                          </div>
                                                          <blockquote
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                                                          <div> This may
                                                          come across as
                                                          high-minded,
                                                          but really I
                                                          just want to
                                                          pass it along
                                                          as something
                                                          that's
                                                          hopefully on
                                                          target. This
                                                          topic forced
                                                          me to go study
                                                          and read and
                                                          I'm looking
                                                          for
                                                          confirmation
                                                          I'm not
                                                          misleading
                                                          anybody.<br
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                                                          <br
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                                                          The specific
                                                          motor control
                                                          application
                                                          that I think
                                                          might be
                                                          relevant to
                                                          Brian's kids
                                                          is treated
                                                          with the
                                                          "freewheeling
                                                          diode"s link
                                                          on this page:<br
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                                                          <br
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                                                            <a
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                                                          rel="nofollow"
                                                          shape="rect"
                                                          target="_blank"
href="https://en.wikipedia.org/wiki/Power_MOSFET#Body_diode"><a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Power_MOSFET#Body_diode">https://en.wikipedia.org/wiki/Power_MOSFET#Body_diode</a></a><br
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                                                          <br
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                                                          Here is the
                                                          transistor
                                                          Brian's kids
                                                          are going to
                                                          use:<br
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                                                          <br
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                                                            <a
                                                          moz-do-not-send="true"
                                                          rel="nofollow"
                                                          shape="rect"
                                                          target="_blank"
href="https://www.fairchildsemi.com/datasheets/FQ/FQP30N06L.pdf"><a class="moz-txt-link-freetext" href="https://www.fairchildsemi.com/datasheets/FQ/FQP30N06L.pdf">https://www.fairchildsemi.com/datasheets/FQ/FQP30N06L.pdf</a></a><br
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                                                          <br
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                                                          This
                                                          transistor can
                                                          handle 32 amps
                                                          of avalanche
                                                          current and is
                                                          specifically
                                                          designed for
                                                          inductive
                                                          loads. The
                                                          body diode in
                                                          this
                                                          transistor
                                                          qualifies as a
                                                          snubber when a
                                                          motor is
                                                          turned off and
                                                          is
                                                          "freewheeling".
                                                          The energy
                                                          will go
                                                          straight to
                                                          ground without
                                                          incident.
                                                          Searching for
                                                          this part
                                                          number and
                                                          "motor" gives
                                                          a number of
                                                          hits where
                                                          hobby folks
                                                          are putting
                                                          rectifiers
                                                          across the
                                                          motor
                                                          windings. This
                                                          strikes me as
                                                          redundant. (At
                                                          this point one
                                                          might think
                                                          "but wait,
                                                          this
                                                          transistor is
                                                          only rated at
                                                          60 volts
                                                          source to
                                                          drain". But
                                                          when the coil
                                                          field
                                                          collapses and
                                                          the source
                                                          voltage shoots
                                                          up the
                                                          transistor
                                                          junction
                                                          "avalanches"
                                                          and begins to
                                                          conduct
                                                          current very
                                                          quickly,
                                                          yanking the
                                                          voltage right
                                                          down close to
                                                          ground. The
                                                          "avalanche
                                                          feature" of
                                                          the transistor
                                                          is
                                                          manufacturing
                                                          technique that
                                                          avoids "hot
                                                          spots" that
                                                          might ruin the
                                                          part.)<br
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                                                          <br
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                                                          Sorry for
                                                          assuming we
                                                          more or less
                                                          knew the
                                                          application:
                                                          wimpy little
                                                          low power
                                                          motors with
                                                          massive
                                                          overkill
                                                          components. 
                                                          And I'm
                                                          probably
                                                          running the
                                                          risk of
                                                          causing folks
                                                          to blow up
                                                          their parts by
                                                          not simply
                                                          recommending a
                                                          separate
                                                          snubber.  It
                                                          may be going
                                                          too far to
                                                          suggest that
                                                          the body diode
                                                          should be
                                                          included in
                                                          the schematic
                                                          when it can be
                                                          considered a
                                                          snubber, but I
                                                          confess this
                                                          the frame of
                                                          mind I'd
                                                          developed
                                                          before the
                                                          discussion
                                                          woke me up.
                                                          I'll be
                                                          reading
                                                          datasheets
                                                          more carefully
                                                          in the future!<br
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                                                          <br
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                                                          Ah, but we
                                                          haven't
                                                          mentioned
                                                          improperly
                                                          switching the
                                                          transistor and
                                                          having it sit
                                                          in its linear
                                                          zone. I claim
                                                          the local
                                                          record for how
                                                          fast a MOSFET
                                                          can desolder
                                                          itself when
                                                          this happens
                                                          at six amperes
                                                          to a small
                                                          SMD. :-)</div>
                                                          <div><br
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                                                          <br
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                                                          -Pete</div>
                                                          <div><br
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                                                          <br
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                                                          <br
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                                                          <div>On
                                                          03/09/2016
                                                          06:44 PM, <a
moz-do-not-send="true" rel="nofollow" shape="rect"
                                                          ymailto="mailto:kschilf@yahoo.com"
target="_blank" href="mailto:kschilf@yahoo.com"><a class="moz-txt-link-abbreviated" href="mailto:kschilf@yahoo.com">kschilf@yahoo.com</a></a>
                                                          wrote:<br
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                                                          </div>
                                                          <blockquote
                                                          type="cite">
                                                          <div
                                                          style="color:#000;background-color:#fff;font-family:HelveticaNeue,
                                                          Helvetica
                                                          Neue,
                                                          Helvetica,
                                                          Arial, Lucida
                                                          Grande,
                                                          sans-serif;font-size:16px;">
                                                          <div>Hi Pete,</div>
                                                          <div><br
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                                                          </div>
                                                          <div>Good note
                                                          about warning
                                                          flags.</div>
                                                          <div><br
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                                                          </div>
                                                          <div dir="ltr">I
                                                          have no idea
                                                          about the
                                                          application. 
                                                          Current in an
                                                          inductor can
                                                          not change
                                                          instantaneously. 
                                                          If you are
                                                          going to
                                                          interrupt the
                                                          circuit, you
                                                          should provide
                                                          a path to
                                                          allow the
                                                          inductor
                                                          current to
                                                          continue
                                                          (catch diode
                                                          in a switching
                                                          power supply)
                                                          or diminish
                                                          (diode across
                                                          a relay
                                                          winding),
                                                          etc.  If not,
                                                          you let Mr.
                                                          Murphy
                                                          determine
                                                          where the
                                                          energy will
                                                          go, sometimes
                                                          with exciting
                                                          consequences. 
                                                          :-)</div>
                                                          <div dir="ltr"><br
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                                                          </div>
                                                          <div dir="ltr">Sincerely,</div>
                                                          <div dir="ltr">Kevin
                                                          Schilf<br
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                                                          </div>
                                                          <div><span></span></div>
                                                          <div><br
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                                                          <br
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                                                          </div>
                                                          <div
                                                          style="display:block;">
                                                          <div
                                                          style="font-family:HelveticaNeue,
                                                          Helvetica
                                                          Neue,
                                                          Helvetica,
                                                          Arial, Lucida
                                                          Grande,
                                                          sans-serif;font-size:16px;">
                                                          <div
                                                          style="font-family:HelveticaNeue,
                                                          Helvetica
                                                          Neue,
                                                          Helvetica,
                                                          Arial, Lucida
                                                          Grande,
                                                          sans-serif;font-size:16px;">
                                                          <div dir="ltr">
                                                          <font
                                                          face="Arial"
                                                          size="2"> </font>
                                                          <hr size="1">
                                                          <b><span
                                                          style="font-weight:bold;">From:</span></b>
                                                          Pete Soper via
                                                          TriEmbed <a
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target="_blank" href="mailto:triembed@triembed.org"><a class="moz-txt-link-rfc2396E" href="mailto:triembed@triembed.org"><triembed@triembed.org></a></a><br
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                                                          <b><span
                                                          style="font-weight:bold;">To:</span></b>
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                                                          <br
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                                                          <b><span
                                                          style="font-weight:bold;">Sent:</span></b>
                                                          Wednesday,
                                                          March 9, 2016
                                                          5:25 PM<br
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                                                          <b><span
                                                          style="font-weight:bold;">Subject:</span></b>
                                                          Re: [TriEmbed]
                                                          N-MOSFET
                                                          Symbol<br
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                                                          </div>
                                                          <div><br
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                                                          I'm pretty
                                                          sure about 70%
                                                          of Brian's
                                                          interest in
                                                          this subject
                                                          involves <br
                                                          clear="none">
                                                          dealing with
                                                          inductive
                                                          loads. The
                                                          body diode in
                                                          the schematic
                                                          symbol is <br
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                                                          a merciful
                                                          hint.  If his
                                                          kids can
                                                          remember that
                                                          the lack of a
                                                          body diode <br
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                                                          is a red flag
                                                          they might
                                                          avoid blowing
                                                          up their BJTs
                                                          or adding
                                                          redundant <br
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                                                          components.<br
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                                                          <br
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                                                          -Pete
                                                          <div><br
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                                                          <br
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                                                          <br
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                                            TriEmbed web site: <a
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                                              target="_blank"
                                              href="http://triembed.org/"><a class="moz-txt-link-freetext" href="http://TriEmbed.org">http://TriEmbed.org</a></a><br
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    </blockquote>
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