Maker Pro
Maker Pro

Do anyone know how to approach this circuit?

J

john ong

Jan 1, 1970
0
R3 Ohm
|-------/\/\/\-------|
| _____________ |
R1 Ohm | |comparator | |
Vin---/\/\/\/\----------------------------|LM139 |---------|<---Vout
| | | |Vref = 1.4v | |
| | | |Supply=+/-Vcc| \
| | | ______________ /
\ C1 F--- ------ \
/ --- |zener | / R4 Ohm
R2 Ohm\ | |diode | |
/ | |5.6v | +|
\ | -------- V1 voltage
| | | -| source
|________|________|______________________________|
|
 
F

Fred Bloggs

Jan 1, 1970
0
john said:
R3 Ohm
|-------/\/\/\-------|
| _____________ |
R1 Ohm | |comparator | |
Vin---/\/\/\/\----------------------------|LM139 |---------|<---Vout
| | | |Vref = 1.4v | |
| | | |Supply=+/-Vcc| \
| | | ______________ /
\ C1 F--- ------ \
/ --- |zener | / R4 Ohm
R2 Ohm\ | |diode | |
/ | |5.6v | +|
\ | -------- V1 voltage
| | | -| source
|________|________|______________________________|
|
----

Yes- I'm sure lots of people know how to solve this- and that's because
they did their homework on their own.
 
T

The Real Andy

Jan 1, 1970
0
john ong said:
R3 Ohm
|-------/\/\/\-------|
| _____________ |
R1 Ohm | |comparator | |
Vin---/\/\/\/\----------------------------|LM139 |---------|<---Vout
| | | |Vref = 1.4v | |
| | | |Supply=+/-Vcc| \
| | | ______________ /
\ C1 F--- ------ \
/ --- |zener | / R4 Ohm
R2 Ohm\ | |diode | |
/ | |5.6v | +|
\ | -------- V1 voltage
| | | -| source
|________|________|______________________________|
|
----

I know how to do it but I ain't tellin' ya cause it sounds like homework.
 
J

john ong

Jan 1, 1970
0
Well guess I have to write something without everyone starts thinking
I'm striving. I had my own answers already but just wanna check if my
approach is correct before handing in my work.

I looked up the application notes of LM139 and I think one of the
circuit analysis is pretty similar to my question. Assuming the zener
diode and capacitor is not there I intend to use the formula VA1 =
+VccR2(R1 + R3)/(R1R2+R1R3+R2R3 and VA2= VccR2R3/(R1R2 +R1R3
+R2R3)found in the application note for LM139. To use that formula I
got to switch the Vcc in the notes with the Vref in my drawing and
vice versa for Vref. Is my approach sound?

Thanks for patient.
 
Top