We found this chopper circuit in a 1967 publication. The transistors are of the time, and current equivalents can be used.
July 2017 - Texas Instruments' new bidirectional current controllers LM5170-Q1 for power...
This circuit provides voltages and a 1 kHz signal for measurement bridges. The circuit is from...
Suggested by National based on the LM6218, this circuit from the 90s has high speed...