[TriEmbed] Driving 32 5v relays

[Richard Prevette]

I am making a Christmas light display using 32 relays.  Using arduino and
four 74HC595n shift registers.
The relays are SRD-5vDC-SL-C.  Here is the question: I may be
misunderstanding but the datasheet states each
relay takes 72ma.  I put  a meter across the power and that seems right.
At one point all relays will be on at the same time.
That looks like I need a power source that will supply about 2.3 amps.  32
x 72 x 1000 = 2.3a (Correct ?)

I have a Dell AC adapter that states output at 14v dc and 3 amps.  All I
need is a resister to lower 14 to 5 volts and
I good to go?
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