Codec enables digital mikes, cancels noise

Maxim Integrated Products announces the MAX9867 stereo audio codec. The low-power codec integrates digital microphone support and programmable digital filters to deliver a richer audio experience to end users. It combines high-quality MP3 playback and extended battery life, and is suited for portable consumer electronics such as cell phones, portable multimedia players, Bluetooth stereo headsets and gaming consoles.

The MAX9867 offers a complete voice record path with stereo differential microphone inputs and stereo single-ended line inputs. Integrated support for traditional analogue microphones as well as digital microphones allows engineers to future-proof their designs.

The device includes a set of programmable digital filters that can be used during audio recording or playback. The filters provide the product designer with a simple method to eliminate system noise, such as the GSM packet frequency (217Hz), from the audio path. They also allow custom noise-cancellation schemes for improved isolation of vocal frequencies. Also, the headphone amplifier incorporates comprehensive click-and-pop circuitry that suppresses audible noise during volume changes, power on, and power off. This circuitry eliminates the large, costly capacitors required by conventional designs.

A low-power audio codec, the MAX9867 consumes a mere 6.7mW during stereo audio playback due to the combination of 1.8V single-supply operation with a highly efficient stereo headphone amplifier. This very low power consumption conserves battery life while ensuring high-quality audio playback in portable devices.

The MAX9867 is available in space-efficient, 2.2mm x 2.7mm x 0.4mm, 30-bump WLP and 5mm x 5mm, 32-pin TQFN packages. It is fully specified for operation over the -40°C to +85°C extended temperature range. Prices start at Rs.46.18 ($0.95) for 10,000-up, FOB USA.