Hi,
My customers are considering the AD 8180.
When 1 kΩ resistor is attached to the output pin, we confirmed the phenomenon that the output voltage drops as compared with the case of no load.
Since the load is increasing, we believe voltage drop will occur.However, the change in output voltage is different between Input positive voltage and Input negative voltage.
Does the output voltage level change depending on the DC voltage level?
Hi Yuya,Output impedance doesn't change on the level of the input voltage, it will only change depending on the frequency as it is not purely resistive, there is reactive elements on it. But the change…
Hi Yuya,Can you share your schematic on your test? What is your input voltage?How do you measure the output voltageWhat value are you measuring with and without the 1kohm load?
I agree with you that the output will be different when the input is positive or negative, this is because the transistor at the outputs(totem pole NPN, PNP) is not that well matched. You can see this on some of the op amp datasheets.Best Regards,Goz
Hi, Goz
I do not have circuit diagrams from customers, so I can not share the evaluation environment.I agreed that the outputs at positive and negative voltages do not match because the transistors do not match.
There is something I would like to ask you with additional.
Q: Does the output impedance change depending on the voltage value input to the AD8180?
Best regards,
Yuya
Hi Yuya,Output impedance doesn't change on the level of the input voltage, it will only change depending on the frequency as it is not purely resistive, there is reactive elements on it. But the change should be very small and sometimes negligible.Regards,
Goz
I was aware.thank you for your answer.