A fast variable transition time pulse generating circuit

A pulse generating circuit has been developed which extends the flexibility of high-speed pulse generators by offering variable transition times from 300 ps up to 1 ns. This is in addition to being able to operate with pulse repetition rates from DC up to 500 MHz and with amplitudes up to 5 V into 50 Omega . A gallium arsenide (GaAs) pin driver IC forms the variable transition predrive pulses that are fed to an output stage using GaAs FETs. A nonlinear gate shaping network is used to clean up the drive signal fed to the differential pair. The overall circuit is implemented using fine-line thick-film hybrid technology and wedge bonding techniques.<>