Wolfson Microelectronics plc has added a stereo audio D/A converter (DAC) with a high output drive capability of 2V rms, eliminating the need for external op-amps in DVD, Digital TV and audio/video receiver electronics.
Designated the WM8521 , the DAC integrates a digital interpolation filter, multi-bit sigma delta with dither, switched capacitor multi-bit stereo DAC and output smoothing filters combined with 2V rms outputs. This high output capability reduces the bill of materials and design effort in equipment including DVD players, digital TVs, digital set top boxes, and A/V receivers, and allows designers to achieve higher performance while minimising build cost.
The multi bit sigma-delta DAC design of the WM8521 includes integrated internal smoothing filters, and includes noise shaping to allow 24-bit audio resolution to be met using non-critical analogue components. The switched capacitor design of the multi-bit stereo DAC maximises clock jitter tolerance and produces low out of band noise. This allows the external low-pass filter to be reduced to a simple RC pole or eliminated altogether. The DAC is available in a 14-pin SOIC package, with three external pins for selection of audio input format, mute control and de-emphasis selection.
The WM8521 supports up to 32-bit I2S, 16-bit right justified, and 16-bit DSP audio formats, and is compatible with a range of industry standard microprocessors, controllers and DSPs. Audio performance specifications include DAC signal to noise ratio (SNR) 103dB and total harmonic distortion (THD) -90dB, both 'A' weighted at 48kHz.
Wolfson Microelectronics plc , Edinburgh EH11 2QB, UK.