DC motors are most commonly used in variable speed and torque applications.

Power supplies are devices that produce AC or DC power.

AC-DC adapters accept AC input voltage directly from a wall outlet, and output DC voltage

Voltage and current signal conditioners amplify or modulate AC or DC current or voltage and process signals to improve transmission

Frequency-to-voltage converters accept a signal and convert its frequency to a corresponding analog voltage level

DC to AC inverters are used for converting direct current (DC) into alternating current (AC).

DC-DC converter chips provide a regulated DC voltage output from a different, unregulated input voltage.