Low Power ADC Invades Portable Audio Markets

Targeting portable-audio applications, the WM8737L a/d converter specifies a SNR of 97 dB with a microphone pre-amplifier noise figure in the sub-µV range. The optimal SNR performance (A weighted) of 97 dB occurs at a normal power mode of 3.3V. In low-power mode, stereo, with microphone pre-amplifiers off, the device draws 8 mW at 1.8V and 18.5 mW at 3.3V. The device's analog and digital I/O lines operate from a 1.8V to 3.6V supply, and the digital core requires 1.42V to 3.6V. Other features include three sets of stereo inputs that are configurable for line-level signals, internal or tabletop microphones, or for dc measurement. A programmable gain amplifier can be enlisted for automatic level control with user programmable hold, attack, and decay times. Available in a leadless, 5 mm x 5 mm QFN package, price is $2.09 each/10,000. WOLFSON MICROELECTRONICS PLC, Edinburgh, United Kingdom. +44 (0) 131 272 7000.