We found this circuit in the Linear Applications Handbook by National Semiconductor. It uses the LM3900, an operational transconductance amplifier as a base. Q1 can be a 2N2222 or similar.
This circuit, found in a 1989 publication, only works with incandescent lamps. The maximum power...
Voltage regulators from 5 to 15 V for currents of 1 A, can be easily obtained in the form of...
This amplifier stage with 1 power transistor was found in the Radio Electronics magazine of...