Reason why opamps are burning out

Using Arduino General Electronics
1

I am using a non-inverting operational amplifier configuration to scale the 3.3V output from an ESP32 with a gain of 1.5.

As a result, I can obtain a voltage range of 0-5V from the original esp 0-3.3V after the operation of the op-amp. When I measure it with a voltmeter, it works perfectly.

opamps
opamps1603×677 46.7 KB

I need to control the motor via the signal wire from the controller.

However, I've encountered an issue where the op-amps appear to burn out, though I'm not sure exactly when this happens.

I suspect it occurs when I disconnect power from the controller and then restore power (cut 42v battery and restore battery connection with controller)

i tried using lmv358 also using mcp6002 but they behave the same way

GND is same as controller and 5v i get from controller, because controller has 3 wires for using potentiometer: GND, 5V, signal

2

Any chance of drawing a diagram that shows the individual op amps in that package?
Like triangles with + & - inputs, an output and a power and ground for the package.

Likewise your power supply side is very vague.

First impressions is that you can't use a potential divider as a power supply for other parts as the voltage out will depend on the current draw. You need to use a voltage regulator.

Operation amplifiers need a signal ground that Is half way between the two power rails of the package, and I don't see that at all on your drawing.

1 Like
3

Most probably your actual wiring is different from the schematic...
If you soldered it: check with a magnifying glass...
And please: keep 5V at top and gnd at bottom...

4

Wiring are 100% like this coz i made in jlcpcb

5

Good luck!

6

That is probably the problem. It's probably not stable when you turn power on/off
Use a separate 5V supply.

1 Like
7

What u mean by not stable. Is there a way to add a protection or something

8

Maybe there is a big spike up to 42V
Do you have a datasheet for this BLDC controller that we can see?

9

nope is chinese one. without datasheet. i try with multimetter and dont see anything strange.

is there any protector IC or something like diode or filter or fuse or... something to protect from big spike

10

Well, assuming the problem is a voltage spike, this circuit will help.
You may also have bad connections and/or bad ground connecions somewhere

image
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11

Do you mean this was a printed circuit board manufactured by some one else?
And all you told them was that child like diagram you posted?

1 Like
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