PGA2500,pdf(Digitally Controll

The PGA2500 is a digitally controlled, analog microphone preamplifier designed for use as a front end for highperformance audio analog-to-digital (A/D) converters. The PGA2500 features include low noise, wide dynamic range, and a differential signal path. An on-chip DC servo loop is employed to minimize DC offset, while a common-mode servo function may be used to enhance common-mode rejection.

The PGA2500 features a gain range of 10dB through 65dB (1dB/step), along with a unity gain setting. The wide gain range allows the PGA2500 to be used with a variety of microphones. Gain settings and internal functions are programmed using a 16-bit control word, which is loaded using a simple serial port interface. A serial data output pin provides support for daisy-chained connection of multiple PGA2500 devices.