如何将LMV324IDT运算放大器作为比较器

你好，
 
 
 你是对的，你可以用运算放大器执行比较器功能。
 如果您担心振荡，可能意味着您的输入信号有点慢，因此会因输入信号上的噪声而导致不同的切换。
 
 为了避免这种情况，我建议基于两个电阻添加外部迟滞。
 我们在应用笔记上进行了开发，重点介绍了比较器的要点。
 您可以查看第17页的第4.2节，其中介绍了外部滞后现象。
 
 本应用笔记可在此处获取：http：//www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00050759.pdf
 
 
 问候，
 西尔



以下为原文





Hello,


You're right that you can perform a comparator fonction with an opamp.
If you are concerned about oscillations, it may mean that you have an input signal that is a little bit slow, thus it will lead to different toggling due to noise on the input signal.

In order to avoid it, I would recommend to add an external hysteresis based on two resistors.
We developed on application note that highlights the main points on comparators.
You can have a look at the section 4.2, page 17, that deals with the external hysteresis.

This application note is available here : http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00050759.pdf


Regards,
Sylvain

你好，
 
 
 我理解你的观点，但你应该考虑的主要因素是外部滞后。
 你肯定可以使用运算放大器作为比较器（因为它不可能使用比较器作为运算放大器）。
 
 权衡的是，对于运算放大器和比较器之间的类似电流消耗，使用比较器可以获得更好的速度（传播延迟和转换速率）。
 但如果运算放大器的转换速率足够您可以使用未通过的通道作为比较器来节省空间和金钱。
 
 此外，关于不良行为的可能性，外部迟滞会避免振荡并为您提供稳健的设计。
 
 问候，
 西尔



以下为原文





Hello,


I understand your point, but the main thing you should take into account is the external hystereis.
You definitely have the possibility to use an op-amp as a comparator (wherease it is not possible to use a comparator as an opamp).

The trade-off is that for a similar current consumption between an op-amp and a comparator, you will have a better speed (propagation delay and slew-rate) with a comparator.
But if the slew-rate of the opamp is enough in your application you can use the unsued channel as a comparator to save space and money.

Moreover, regarding the possiblity of mi***ehavior, the external hysteris will avoid oscillations and will provide you with a robust design.

Regards,
Sylvain

得到它，感谢您的反馈（没有双关语）。



以下为原文







Got it, thanks for the feedback (no pun intended).