LONDON Mobile phone chip joint venture ST-Ericsson NV has announced that it is sampling an audio quality digital-to-analog converter (DAC) for use in the mobile music market.
The STw5211 combines something called a Playback Time Extender with 102-dB of signal-to-noise ratio across the whole audio path. The chip should allow mobile phone companies to make music phones while doubling typical 10-hour playback times. The STw5211 is packaged in a wafer-level chip scale package.
ST-Ericsson did not state what resolution the DAC operates from but for audio applications this should be 24-bit digital data. The chip is implemented in 0.13-micron CMOS and by incorporating the power management circuitry, the device can be directly connected to the battery with no need for external voltage regulators. Additionally, the headset amplifier is of “true ground” type and does not need coupling capacitors, ST-Ericsson said.
Total harmonic distortion is 66-db with sampling rate conversion at between 8- and 192-kHz clock frequency. The device operates from a power supply of between 2.7 and 4.8-V and power consumption and dynamic range adjustable are adjustable and the power consumption at highest resolution is 27-mW with option to go to 5-microwatts in standby.
“Typically, power consumption increases as features are enhanced and quality improved; however, STw5211 with PTE technology allows music to be played autonomously while the rest of the platform is switched into a power-saving state,” said Monica de Virgiliis, vice president of the Wireless Multimedia Group at ST-Ericsson, in a statement.
Volume production of STw5211 is planned for August 2009, with samples available in April.