LM358 op-amp



I have constructed a circuit as below to convert the input of 12 to
24V as 0 to 12V and show the voltage on a DC volt-meter. The
schematics is shown below:


VCC +24V
+
|
.-.
| | +24V
2k2| | VCC
'-' +
| |
| 10K |\|
| +12V-|___|-+--|-\LM358
| ___ | | >---+-----+
IN +-|___|---+-----|+/ | |
| 10K | | |/| | |
| | | === | |
.-. | | GND | |
| | | | ___ | |
2k2| | .-. +--|___|--+ /+\
'-' | | 10K ( )
| 10K| | VOLT \-/
| '-' |
=== | |
GND | ===
=== GND
GND

(created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de)


I have the +12V reference taken from a TL431.

When the input voltage at "IN" is +12V I was not able to get a 0V on
the voltmeter. Instead I am getting 0.58V at the output. Does this
has something to do with the CMRR of the chip? How would I solve
this problem? Would changing the op-amp to LM748 and connecting a
pot between the balance inputs of the LM748 help to reduce the
voltage to O?

Thanks In Advance!

Allen
.



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