目�?�?用的LM358芯片，�?�电压跟�?器，出现输入电压V+为0V时输出电压有�??几�?

[QLiu.2]

现在有一个项目上用了LM358�?放，�?�电压跟�?器用，用在电机上的，现在出现的问题如下：358是15V供电

�?�了一百多�?��?��?，有差�?多五六个出现了下述情况，�?良的芯片输入电压V+为0V时输出电压有�??几�?，�?良的芯片正常工作时，输出电压�?�是正常的，�?�是输入电压是多少输出电压就是多少。

项目比较急，麻烦尽快帮分�?下原因​

原�?�图如下:

​

[Peter BENSCH]

I've translated your question using a translation tool to increase the chances of getting you a reply from our experts and community members, since the majority interact in English:

Now there is a project that uses LM358 op amp as a voltage follower and used in a motor. The problem now is as follows: 358 is 15V power supply.

I have made more than 100 boards, and about five or six of them have the following conditions. When the input voltage V+ of the bad chip is 0V, the output voltage is more than ten volts. When the bad chip is working normally, the output voltage is normal again, namely It is the output voltage as much as the input voltage.

The project is urgent, please help analyze the reasons as soon as possible​

The schematic diagram is as follows:

The outputs of the LM358 directly drive a 10µF capacitor, which is definitely too much and can lead to oscillations or, as in your case, to a latch-up. A latch-up can usually be reset by a power-on reset, but can occur again if the cause is not resolved.

Please consider to insert a resistor of e.g. 820 ohms (min 470 ohms) between the output of the LM358 and C5/C8 if you need some kind of a low pass filter.

If the problem is resolved, please mark this topic as answered by selecting Select as best. This will help other users find that answer faster.

Good luck!

/Peter