Fabless companies have a great opportunity to develop truly unique niche products. Wolfson Microelectronics is taking that opportunity.
Most new digital still cameras can record short full-motion segments with sound. The DSP core in Wolfson's WM8974 codec provides a wind-noise filter, a notch filter to remove zoom-motor noise, and a five-band equalizer (see the figure). Also, its mike preamp boasts automatic level control and an output stage with drivers for speakers and headphones. The codec operates down to 2.5 V (1.62 V in standby mode) and draws less than 10 mA during playback.
The two-channel WM8216 multifunction printer/scanner analog front end (AFE) has a 60-Msample/s conversion rate at 10 bits. Both channels support correlated double sampling. Internally, the chip offers a programmable-gain amplifier and a 4-bit digital-to-analog converter (DAC) that can be used as a clamp for CCD imagers or as a reference for contact-image-sensor designs.
The 2-VRMS output of Wolfson's WM8521 audio DAC eliminates external op amps in the audio chain. The chip integrates a digital interpolation filter, a multibit delta-sigma with dither, the stereo DAC itself, and smoothing filters. SNR is 103 dB, and THD is 90 dB. The input supports 32-bit I2S and 16-bit right-justified and DSP audio.
The digital camera codec costs $2.04, the scanner AFE costs $3.73, and the 2-V output DAC costs $0.97, all in 10,000-unit lots.