PGA2505 麦克风前置放大器
增益范围：0dB 和 9dB 至 60dB，3dB 步进
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 used to enhance common-mode rejection.
The PGA2505 features a gain range of 9dB through 60dB (3dB/step), along with a unity gain setting. The wide gain range allows the PGA2505 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 PGA2505 devices. Four programmable digital outputs are provided for controlling the external switching of input pads, phantom power, and high-pass filters. The PGA2505 requires both +5V and -5V power supplies and is available in a small SSOP-24 package.
PGA2505,pdf datasheet (Digitally-Controlled Microphone Preamplifier)
特性
- 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 = 150 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 Ports
- Supports Daisy-Chaining of Multiple PGA2505 Devices
- OVER-RANGE OUTPUT PIN PROVIDES CLIPPING INDICATION
- FOUR GENERAL-PURPOSE DIGITAL OUTPUT PINS
- ±5V POWER SUPPLIES
- AVAILABLE IN AN SSOP-24 PACKAGE
- APPLICATIONS
- MICROPHONE PREAMPLIFIERS AND MIXERS
- DIGITAL MIXERS AND RECORDERS
- DIGITAL AUDIO EDITING SYSTEMS
- BROADCAST EQUIPMENT
- INTERCOMS