Voltage Regulator: Low Voltage Applications in Circuits

[ACLerok]

This may be a dumb question but I guess it won't hurt to ask. Is there a reason to use a voltage regulator to obtain a lower voltage from a certain set power supply voltage over using a voltage divider? I guess I'm talking low voltage applications in circuits not high power electronics.

 

[N468989]

the output of a voltage regulator is "independente" of its input, thus keeping the voltage constant for any input, on the other hand the voltage divider will change its output once the input voltage changes.

 

[Mike Phan]

if using a voltage divider, make sure that your application current is NOT higher than that of the voltage divider. some devices are fixed voltage regulators, others are adjustable voltage regulators. for example, 7805 is fixed 5V regultor, LT1074 is adjustable voltage regulator from which we can bias to have our desire output voltages.

 

[berkeman]

So to summarize, the voltage regulator holds a fixed output voltage, independent of Vin variations, and independent of Iout variations (within datasheet specifications for the regulator, of course).