I'm trying to amplify a low signal with square pulses at 20 mV using op amps. According to simulation, rise and fall time of pulses increase too much after amplification, approximately 60 us. The component which will receive the signal accepts maximum 300 ns, the datasheet says so.
What kind of things can be done to reduce rise/fall time after amplification or to solve this problem? If I should choose another op amp, which is the best for this purpose?
I have another solution in my mind but I'm not sure. If I shift reference clock a little bit so that rising edges of clock don't meet the rising edges of signal(which are too long), will it work properly?
To see the details of application I'm working on it, visit the following question:
How to amplify a signal containing square pulses at milivolts to a couple volts
Best Answer
An ideal op-amp will amplify and not distort. Unfortunately op-amps are not perfect and to amplify edges you need quite a high gain-bandwidth-product (GBP). GBP tells you about the speed of the op-amp and can be found in the data sheet. Also, an op-amp has another parameter called "slew rate". This tells you how fast the op-amp output can move in volts per microsecond.
An op-amp with a slew rate of 1V/us will easily cope with a small signal but at higher levels of amplification the edges will begin to have finite ramp speeds and eventually a square wave will look more like a triangle wave.
Choose your op-amp carefully.