Voltage Reference Vs. Voltage Regulator

[ee484]

voltage regulator versus voltage reference

Hi, all.

I have used voltage regulator as my reference. But, I have currently known there was a device called voltage reference. I would like to make a good voltage reference for my ADC and wondering if voltage regulator would do the job pretty well or not. Voltage reference is much better than voltage regulator for referencing voltage for a ADC?

For example, if Nyquist ADC is being used, and it requires refence votlage since it does not have bandgap reference in it. Which one would you like to use?

Any comments? Pros and cons?

Thanks,

Best,
B

 

[surianova]

voltage reference only can drive resisitive load unless use together with buffer. Voltage regulator can use to drive resistive and capacitive load.

 

[forkschgrad]

hi,

can you suggest some good books discussing their difference. My idea is voltage reference is used as voltage source. Is voltage reference a form of voltage regulator? tnx.

 

[surianova]

hi,

can you suggest some good books discussing their difference. My idea is voltage reference is used as voltage source. Is voltage reference a form of voltage regulator? tnx.

i don't have book. but basiaclly

1. Voltage regulator need a reference for the input. So, the input is voltage reference.

2. Voltage reference normally a bandgap which is independent of power supply and temperature.

3. Actually u can straight use the voltage reference to drive your circuit with a buffer, but nomally u need higher voltage. So, u use non-inverting confuguration to bring the DC voltage higher like voltage regulator.

4. other difference is the reference voltage has high output impedance and regulator has low output impedance.


5. If your voltage is used to drive gate or capitance, voltage reference with high output impedance is good enough.

 

[leo_o2]

In my opinion, voltage reference has very small driving capability (<several mA depends on product) while voltage regulator can usually drive up to several hundreds of mA or even several A.
Voltage regulator also has fast response according to big driving capability. For ADC, I suggest voltage reference because big driving capability is not necessary. And many voltage references will have better TC than voltage regulator. TC might be a very important parameter for ADC reference like various meters application.

 

[tia_design]

Voltage Regulator is too expensive. If the circuit is Switch Cap, then using DAC to generate reference signal

 

[stocol]

regulator,i think u mean ldo,serve as power supply.
i think what u need for ur adc is volt ref,generally bandgap voltref.
it needs trimming to obtain accurrate value