Below is a schematic of a preamp designed by RJB for a power line communications chip designed by ITRAN communications. The process used is Tower Semiconductors 0.35 um process. The gain of the pre-amp was set to 23 dB. The output clippling was accomplished using the source follwer and the diode connected load (in series with a current sink.) The layout shown below also shows the op-amp used to drive an off-chip low impedance filter.