We found this circuit in the Linear Applications Handbook of the 1994 National Semiconductor. The transistor must be a high voltage type and the LM3900 power supply must be symmetrical.
The circuit shown is from old English documentation and can be made with BC548 transistors for low...
The circuit shown can measure currents less than 1 uA and is powered by two 1.5 V batteries in a...
This circuit uses old Japanese transistors, as it was found in a 1968 magazine published in that...