Audio codec packs features

AKM Semiconductor introduced a multifunction audio codec for digital televisions, home theater systems, DVD receivers and automotive amplifiers.

This versatile chip integrates a 2-channel analog-to-digital converter (ADC), a 4-four channel digital-to-analog converter (DAC) sampling at 192KHz, a headphone amplifier and a 192kHz compatible Sony/Philips digital interface (S/PDIF) transceiver.

Both converters feature 24-bit resolution, with dynamic range of 100dB (ADC) and 106dB (DAC). The analog input stage has a preamp with a 6-channel input selector. The preamp input range can be easily configured with external resistors to tolerate input signals above a 5V power supply, such as 2V rms (up to 4V rms). The post-ADC digital volume controls allow for channel-independent level adjustments from 24dB to -103dB.

The AK4683's D/A converter has four output channels and integrated digital volume controls for channel-independent adjustment of the level from 12dB to -115dB. Two of the four channels have both headphone and line outputs, and the headphone output features a mute circuit that eliminates the need for an external circuit to suppress pop noise generated when power is switched on/off.

The AK4683's digital audio interface conforms to AES3, IEC60958, S/PDIF and EIAJ CP1201 interfaces. The digital audio transceiver is compatible with 192 kHz, 24-bit data, and can be operated asynchronously from the codec. The digital/audio interface receiver (DIR) has a 4-channel input selector and interfaces with many digital audiovisual (AV) devices, as it detects both pulse-code modulation (PCM) and non-PCM data, such as Dolby Digital.

The serial audio interface for a digital signal processor (DSP) has two ports and each A/D converter, D/A converter and DIR/DIT (transmitter) block can be operated asynchronously. The audio format is compatible with time division multiplexer (TDM) systems and pre-packed and post-packed I2S, which simplifies the DSP interface.

The AK4683 is available in a 64-pin LQFP for $4.40 each in 10,000-piece orders.

- Bettyann Liotta