Tool/software:
Hello Team,
I am using the TLV9151S op-amp in my project and encountering an issue. When the op-amp is disabled, I observe a voltage of 10 to 12 mV at its output pin.
I have attempted to pull down the output pin, but it had no effect on reducing the voltage. Could you please suggest a configuration or solution to bring this output closer to zero?
Thanks
Rohit Gupta
Hi Gohit,
It seems that TLV9151-Q1 has the residual output voltage at its output under no load (for single supply rail configuration).
The simplest method is to AC couple the output. If you are unable to implement that in the application, then you may have to change the op amp, such as OPA197-Q1 or similar automotive op amp. TLV9151-Q1 is a general purpose op amp, and the application may require precision op amp type. There are other techniques to make the Vos to GND, but it is not worth the effort for the application (it is easier to replace the op amp).
https://www.ti.com/amplifier-circuit/op-amps/precision/products.html#1498=Automotive&sort=1130;asc&
The Vos issues are due to imbalanced input resistor matching and general purpose op amp does not have internal resistor trim process. You may be able to add to the input circuit, but it is not worth it. It is also possible due to the high gains in the circuit.
If you want to send me the schematic, I can see if there is an easier solution. Replace it with a precision op amp will be simpler, if you are concerned about he mV offset voltage under no load.
Best,
Raymond
