generate voltage reference

crutschow

Joined Mar 14, 2008
38,598
Below is the LTspice simulation of a reasonably stable Zener reference circuit.
It uses a 5V Zener for good temperature stability, with an op amp to generate the bias current for the Zener from the Zener voltage itself, and give a low impedance output.
The circuit Zener and output voltages are thus basically insensitive to supply voltage changes, and output load.
The op amp gain is +1.2 so the output is 6V (green trace) from the 5V Zener (yellow trace).
The Zener bias current is 5mA.
R4 generates a small positive bias to insure that the circuit starts on power up.

This is probably about as good as you can get without going to a dedicated voltage reference IC.

1648412046602.png
 
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ci139

Joined Jul 11, 2016
2,008
V-ref - TEST - XP-010.pngMy "Mad Professor" variant . . . it is not an example to be built - but an illustrative example how the preceding and follow up circuitry may worsen or improve the reference precision . . . + a more realistic v. for the LT1635
& a more likely behaviour for the * LM317 TL431 composite (i never verified my ←models*← for temperature) → →
V-ref - TEST - XP-030.gifV-ref - TEST - XP-040.png
 
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Thread Starter

k1ng 1337

Joined Sep 11, 2020
1,038
Thanks to everyone, the information provided has been helpful. Instead of asking a million questions, I will return to the literature as well as become proficient in LTspice. I'll surely return with more questions as I find power conversion a particularly interesting topic. Think youtube ads suck? I seen two this week about power conversion hosted by AAC. For an ad video I learnt quite a bit, how bout that?
 
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