OP07
Not Recommended for New Designs
Datasheet
OP07 on Analog.com
Hey there!
I've designed a two-stage amplification circuit using the ADA4898 IC. My input signal ranges from 0.2mVp-p to 3mVp-p with a fixed frequency of 32.768 kHz, and I've applied a gain of around 10,000V/V.
Now, I'm stuck at the Schmitt trigger stage. I need to convert my output signal, which is currently a sine wave, into a square wave. However, I'm having trouble designing a proper Schmitt trigger circuit. Could you please suggest a suitable Schmitt trigger design using the OP07 or any other appropriate IC? I'm aiming for a final output of around 3Vp-p in a square wave.
I'll also share my current schematic with you to help you understand my setup better.
Hello OpAmp,
I would not recommend using an op amp such as OP07 and configuring it as a comparator. It is better to use an actual comparator part rather than using an op amp and configuring it as a comparator. Op amps are not designed to be used as comparators since it is possible for them to saturate if overdriven. As an effect, they will recover comparatively slowly. On the other hand, comparators are designed to drive logic from their outputs, work open-loop, and work at high speed with minimal instability. For more details regarding the use of op amps as comparators, you may check this article: MT-084: Using Op Amps as Comparators (analog.com)
For the design of a Schmitt Trigger circuit, you might want to check this link: Activity: The Comparator, Positive Feedback and Schmitt Trigger, For ADALM1000 [Analog Devices Wiki]
You may also check our comparator products here: Comparators | Analog Devices for a comparator part that will suit your application.
Best regards,
Paul
Okay, thanks for the update. I’ve designed the circuit, and I’m sharing it here. Please check it and let me know if any changes are required. Also, kindly suggest the correct approach and provide any solutions or layout guidelines, if applicable.
Hello OpAmp,
Can you please send again an image of your schematic? I can't see what parts and components you have used, even though I'm already zooming into the picture because it is already blurry. Thank you very much.
Best regards,
Paul
Hello again,
I saw that you have posted another question here: (+) Circuit approach - Q&A - Operational Amplifiers - EngineerZone (analog.com). With that, I'll close this thread to avoid multiple open queries. Thank you very much.
Best regards,
Paul