Maxim Integrated Products introduces the MAX9867, a stereo audio codec that integrates features such as digital microphone support and programmable digital filters. Offering a combination of MP3 playback and extended battery life, the chip is suited for portable consumer electronics such as cell phones, portable multimedia players, Bluetooth stereo headsets, and gaming consoles. The device offers a complete voice record path with stereo differential microphone inputs and stereo single-ended line inputs.
Integrated support for traditional analog microphones as well as digital microphones allows engineers to future-proof their designs. For enhanced audio performance, the device includes a set of programmable digital filters that can be utilized 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. Additionally, 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. The codec 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. 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 $0.95 (10,000-up, FOB USA).