[sdiy] When to use voltage regulators and when to use resistors?

[James R. Coplin]

Probably a pretty silly question but I'm wondering when to consider voltage
regulators versus knocking down voltage with resistors.  In my particular
case, I'm adding some modules to my rack mounted SEMs.  The SEMs run off of
18.5v but the additional circuitry I want to add expects 15v.  Should I put
a 15v regulator on or can I just pad down the 18.5 volts coming from the
power supply with appropriate resistor values?  I have plenty of spare
amperage in the supply to handle the additional modules, I'm just not so
sure about getting the voltage down to the 15v. Thanks!

James R. Coplin
(郭杰明)

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Work is the Curse of the Drinking Class
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