LM358: Function of LM358 in circuit inverter

Thanks you!

Hi Lai,

from where is this schematic? Have you a link?

In the first schematic LM358 and LM324 seem to be part of a PID.

In the second schematic circuitry at input of LM358 looks strange. Shall this be an input bias current cancelation? Strange...

Kai

Hi Kai,

Update schematic final. I draw schematic from a circuit board of micro x-ray manufacturer Kevex.

 

Hi Ron Michallick,

I checked pin 4 connected GND and pin 8 connected Vcc 

Ron Michallick,
I think test point is input signal.

Hi Lai,

I don't think so. The input signal should be applied to the upper end of R14, where you have made a connection to GND. The pot R15 in combination with R13 and R14 could form an adjustable voltage divider.

Ron asked you to measure the potentials at pin 4, pin 8 and the test point. Have you done this? Could you please give us the results?

Kai

Hi Kai,

PIN 4 = 0V, PIN 8= 5V

Hi Lai,

and what do you measure at the test point?

Kai

Hi Kai,
Test point = 0V
Hai

Hi Lai,

is your question answered now?

Kai