The HA13173H is a multiple voltage regulator for car audio system. This IC has 5.0 V output for a microcontroller, 3.3 V output for a Digital Signal Processor, 8.0 V output for CD driver, 8.4 V output for audio control, 8.4 V output for illuminations, and high side switch output for external output. The HA13173H also has FREG that is possible to control external PNP transistor. It is adjustable output voltage by changing an external resistor.