The difference between the input and output voltages of the voltage follower is so large that I was confused for several days. Please help me.

小鸡咯咯哒

The difference between the input and output voltages of the voltage follower is so large that I was confused for several days. Please help me. [Copy link]

I made a voltage follower with OPA4180. The input and output are quite different. The input is 7V, the output is 12.4V, and the chip power supply is 14.8V. I disassembled it into two 560K and 10

After that, the voltage after the follower is 0V. I thought the chip was broken, so I replaced it several times, but it still didn't work. I found information online that OPA4180 is rail-to-rail. Does rail-to-rail voltage follower require a special circuit? Please give me some advice.

chunyang

Refer to the device manual to check whether the pin connections are correct.

maychang

An op amp does not require any "special circuitry" to function as a follower.

From the electrical schematic, the pin numbers are correct. This abnormal phenomenon is mostly caused by power supply or welding problems. You can only check it carefully by yourself.

maychang

I don't know why the original poster used three LM339 voltage comparators. I think only one is enough.