Audio codec integrates capless headphone amplifier

San Jose, Calif. — AKM Semiconductor released a low-power audio codec with an integrated capless headphone amplifier for mobile phone, smart-phones, music players and personal media players.

The 20-bit AK4665A audio codec has an integrated charge pump circuit, which creates a negative power supply for the headphone amplifier. This allows the audio signal to be ground referenced, thus eliminating the need for external DC blocking capacitors, the company said.

The codec also features a power-on mute circuit for 20-millisecond pop-free on/off switching. The analog power supply range is 2.6 volts to 3.6 V, while the digital power supply for the external control interface operates as low as 1.6 V.

The AK4665's digital recording automatic level control (ALC) enables a high-quality recording platform that also cuts power consumption, according to AKM Semi. Power consumption is 54 milliwatts for the codec.

The AK4665A includes a dedicated stereo lineout with a volume control that is independent of headphone output, enabling separate level control of an external device such as a stereo speaker amplifier. Differences in multi-source recording levels are adjusted by an output ALC circuit, ensuring constant playback volume.

The AK4665A codec also features an integrated programmable gain amplifier (PGA) microphone amplifier, integrated microphone power supply, playback volume control and bass boost, stereo and mono auxiliary analog inputs, independent power management for each circuit block, and a three-wire serial control interface.

See related block diagram

The AK4665A is available now in a 32-pin QFN, with a footprint of 25-mm squared and a height of 1 mm. Pricing starts at $2.44 in 10,000-piece quantities. Click here for the AK4665A data sheet.

AKM Semiconductor , 1-888-256-7364,

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