High Speed Switch Amp OC interface

amplifier for 5v open collector low power comparator output for high speed switching. at 1MHz it's not possible to switch a basic common emitter amplifier without swamping it with Miller capacitance. I want to switch this bastard without wiping out bandwidth. came up with this. from left to right, tie the Open collector output to a common base amp Q1 to get a good voltage swing and higher impedance. this is directly coupled to the common collector amp Q2 to increase current. Q2 is directly coupled to Q3, a common emitter. positive feedback from Q3 goes back to the emitter of Q2 and the base of Q1 and also connects the drive line to Q4, which is also the collector load of Q3. i think that's what's happening anyway. could very well be bullshit.

published 8 years ago