PGA2505 - Texas Instruments

PGA2505 MICROPHONE PREAMPLIFIER

The PGA2505 is a digitally-controlled, analog microphone preamplifier designed for use as a front-end for high-performance audio analog-to-digital converters (ADCs). The PGA2505 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 .

Features

1
•234 FULLY DIFFERENTIAL lNPUT-TO-OUTPUT ARCHITECTURE
• DIGITALLY-CONTROLLED GAIN USING SPI™:
  – Gain Range: 9dB through 60dB, 3dB per Step
  – Unity (0dB) Gain Setting via Serial Port
• DYNAMIC PERFORMANCE:
  – Equivalent Input Noise with ZS = 150Ω and Gain = 30dB:
  –123dBu
  – Total Harmonic Distortion plus Noise (THD+N) with Gain = 30dB: 0.0006%
• ZERO CROSSING DETECTION MINIMIZES AUDIBLE ARTIFACTS WHEN GAIN SWITCHING
• INTEGRATED DC SERVO MINIMIZES OUTPUT OFFSET VOLTAGE
• COMMON-MODE SERVO IMPROVES CMRR
• FOUR-WIRE SERIAL CONTROL PORT INTERFACE:
  – Simple Interface to Microprocessor or DSP Serial .