modified 5 months ago

Improved Howland Current Pump

00:50:19

The difference amp (Howland portion) converts the signal source on the left to a constant current.  The bipolars boost the current through the common emitter configuration. That output goes through the load resistors located at the bottom right corner near ground (4 ohm & 20 ohm resistors).  The vertical resistor (3 ohm) sets the current for the load.  If you set this resistor lower than 3 ohms you will latch one of the transistors and break the oscillation.

published 5 months ago

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