Why too low frequency of Negative capacitor using opamp?
时间:04-08
整理:3721RD
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hi, all. I need realize negative capacitor from 80MHz to 108 MHz by NIC using opamp, the opamp 3-dB bandwidth is 150MHz. But the negative cap can be got under 1.5MHz.
Anyone can help to explain why?
Anyone can help to explain why?
anyone can help?
Can you share the design?
I doubt, that the loop bandwidth will be 150 MHz, I guess, it's rather the unity gain bandwidth respectively GBW product.
In any case, a much higher OP bandwidth would be necessary to generate almost capacitive behaviour.
Circuit stability is another topic.
Thanks a lot. I change to LMH6703, and simulated by ADS, achieve good negative capacitor in FM band. I would upload the design after testing
