canadianpoet2012
New Member
I am designing a PIC controlled signal generator. It can produce square, sine and triangle waves as well as PWM signals, RS232 signals, and simple mono and astable waveforms. The maximum output frequency is 25MHz, and the output voltage ranges from 0 - 20v peak to peak.
I am really struggling with the I/O buffer circuits and the variable gain circuit for the O/P. I have done quite a bit of digging on the web and have come across some buffer ICs, as well as digitally controlled potentiometers.
One of the buffer ICs I have found is the LMH6559 high speed, closed-loop buffer. Is it possible to introduce a feedback circuit with this IC to introduce gain for the O/P? Could the same buffer circuit be used for both the input and the output, without any gain for the input?
All of the digital potentiometers I have come across will only accept a maximum of +5v. If it is possible to include gain on a buffer IC this isn't a problem, but if it isn't does anyone know how to use one of these ICs in a gain stage? I am reluctant to use op-amps because of there limited bandwidth and slew rates, I am trying to keep my costs to a minimum.
Any information or suggests are most welcome. Thank you and merry Christmas!
I am really struggling with the I/O buffer circuits and the variable gain circuit for the O/P. I have done quite a bit of digging on the web and have come across some buffer ICs, as well as digitally controlled potentiometers.
One of the buffer ICs I have found is the LMH6559 high speed, closed-loop buffer. Is it possible to introduce a feedback circuit with this IC to introduce gain for the O/P? Could the same buffer circuit be used for both the input and the output, without any gain for the input?
All of the digital potentiometers I have come across will only accept a maximum of +5v. If it is possible to include gain on a buffer IC this isn't a problem, but if it isn't does anyone know how to use one of these ICs in a gain stage? I am reluctant to use op-amps because of there limited bandwidth and slew rates, I am trying to keep my costs to a minimum.
Any information or suggests are most welcome. Thank you and merry Christmas!