Edinburgh, UK Wolfson Microelectronics plc has launched a stereo audio codec that can operate the A/D converter and D/A converter at different sample rates simultaneously.
This feature, intended for use in DVD-RW, LCD TV and similar applications that require the simultaneous playing and recording of DVD or TV content, allows a single small codec chip to be used in place of two separate analog-to-digital (A/D converters) and digital-to-analog (D/A converters). The codec also includes an analog programmable gain amplifier (PGA), which can be used to adjust the sensitivity of analog inputs and it can be used as a limiter to avoid analog input overload distortion.
The WM8591 is a single-ended input, two-wire control version of the WM8590 with a D/A converter signal-to-noise ratio (SNR) of 110dB, combined with a 102dB A/D converter. Unlike many conventional solutions, which require multiple control systems, this single two-wire interface offers access to all features including volume control and mute and de-emphasis facilities.
The codec is based on a 24-bit sigma-delta A/D converter with programmable input gain and limiter control. Analog gain can be adjusted from +24 to -21dB in 0.5dB steps, while digital gain can be programmed from -21.5dB to -103dB, also in 0.5dB steps. Output word lengths from 16- to 32 bits are supported, along with sampling rates from 32 to 96 kHz. The device's audio data interface supports I²S, left-justified, right-justified and DSP formats. The D/A converter supports sampling rates from 32 to 192 kHz, which can be programmed independently of the A/D converter sample rate.
The WM8591 is available to sample now and will be available in volume in Q4. Pricing is $1.45 in 10,000-piece quantities. Click here for the WM8590 and WM8591 data sheets.
Wolfson, 1-858-676-5090, www.Wolfsonmicro.com