CODEC Brings Sound, TV connectivity to Digital Cameras
Wolfson Microelectronics launched the WM8941, a high-performance low-power CODEC with an integrated video buffer and speaker driver for use in digital still and video cameras. The mono CODEC uses four programmable notch filters to provide quality audio recording, while the integrated video buffer provides direct connectivity to a television. The company integrated the CODEC, video buffer and speaker driver in a 4 mm ×4 mm chip. The chip features a wind filter and four programmable notch filters in the ADC path, enabling the WM8941 to be tuned, suppressing narrowband noise. This includes motor and mechanical noise. The current mode video buffer gives a seamless transition from a video DAC output to TV input and provides programmable gain of 0 dB or 6 dB. A third order low pass filter also assures video buffer quality, removing undesired images from the unfiltered video DAC output. In addition, the company provided an on-chip speaker and headphone driver. The headphone driver supports 40 mW output power into 16 ohm. Three flexible analogue inputs are provided: one auxiliary input and two for microphones -- supporting differing configurations of single-ended and differential inputs.