Series-pass voltage regulator

Thread Starter

notoriusjt2

Joined Feb 4, 2010
209

t_n_k

Joined Mar 6, 2009
5,448
The key elements are the zener diode voltage and the values of R2 & R3.

R2 & R3 form a voltage divider across the output. The LM741 op-amp will attempt to control the output such that the R2 + R3 divider output voltage fed back to the LM741 negative input is the same as the zener voltage.
 

Thread Starter

notoriusjt2

Joined Feb 4, 2010
209
i guess you could call it the top of R2.

between R2 and R3 is 5.6V

the bottom of R3 is GND

is this not correct?
 

Ron H

Joined Apr 14, 2005
7,012
i guess you could call it the top of R2.

between R2 and R3 is 5.6V

the bottom of R3 is GND

is this not correct?
I think you have figured it out. I just thought it would make more sense if you called the junction of R2 and R3 Vin, and the top of R2 Vout, since that's how it's labeled on the schematic.
If you do that, Vout/Vin=(R2+R3)/R3.
If you want to communicate using schematics, it is helpful if you stick to the labeling and reference designators on the schematic.
 
Top