3W Mono Class-D Audio Amplifier

General Description

The ALC1003 is a mono Class-D audio amplifier with a typical 4Ω speaker impedance, a 5V power supply, and maximum output power of 3W. The ALC1003 provides configurable input to output gain ratio, with no external components required.

For input signals, the system designer can easily choose 11dB, 14dB, 19dB, or 25dB boost gain by pulling high/low two control pins. With Class-D amplifier technology, the ALC1003 offers good audio quality, high power-efficiency, and requires fewer external components. With analog input support, the ALC1003 can also be used as a Class-AB amplifier.

The ALC1003 can output power directly to the speaker, with less power dissipation inside the silicon. This high efficiency with less run-time power consumption can extend the battery life for portable consumer electronic devices and Notebook PCs.


  • Single-Ended analog input
  • BTL (Bridge-Tied Load) output power: Po = 3W at 4Ω load and 5V power with 10% THD+N ratio
  • No external output L-C filter required
  • Supports pop noise suppression
  • Configurable input to output boost gain ratio (+11dB/+14dB/+19dB/+25dB)
  • Speaker amplifier power supplies from 3V to 5.25V
  • 10µA Shut Down current
  • DFN-12 package


  • Notebook PCs
  • Portable Navigation Device
  • Feature Phone, PDA phone, and Multimedia phone
  • Digital Photo Frame