The circuit shown is from Motorola's 1990 Linear Databook. Shaded components are optional. The characteristics of the coils are given next to the diagram.
This circuit can be used to control loads up to 500 mA from the outputs of microcontrollers such...
This circuit with transistors in parallel was found in a Radio Electronics of August 1952....
This Linear Technology circuit can measure currents from 100 pA to 100 uA. The circuit is from the...