This circuit with output powers of 2 to 3 W depending on the power supply was found in the magazine Radio Electronics of April 1990. The speakers are 8-ohm.
This circuit is from the LM317's own manual obtained from an old documentation. The IC should be...
This CMOS circuit was found in the July 1990 Radio Electronics magazine. Power is for a 12V...
It can be obtained from Mouser Electronics new evaluation module for 1A stepper motors control...