I'm playing around with BJT amplifiers and have some questions regarding the gain rolloff you see at higher frequencies, I'm using the 2N2222 for my tests and my simulations and measured results match up pretty well, example below:
So at 3MHz or about I see my rolloff start affecting my gain, which is described in another answer, at around 18MHz the gain drops to 0dB. My questions are:
- Is this rolloff caused by the Miller effect?
- If not caused by the Miller effect what is the cause?
- Can you compensate for the gain rolloff to some extent or do you need to choose a faster BJT?. I've played around with the input impedance which I thought would help but this made little difference.