PG
A2
505
Burr-Brown Audio
www.ti.com
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SBOS396B – MARCH 2009 – REVISED JUNE 2009
™ Digitally-Controlled
MICROPHONE PREAMPLIFIER
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FEATURES
APPLICATIONS
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MICROPHONE PREAMPLIFIERS AND MIXERS
DIGITAL MIXERS AND RECORDERS
DIGITAL AUDIO EDITING SYSTEMS
BROADCAST EQUIPMENT
INTERCOMS
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FULLY DIFFERENTIAL lNPUT-TO-OUTPUT
ARCHITECTURE
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DIGITALLY-CONTROLLED GAIN USING SPI™:
– Gain Range: 9dB through 60dB,
3dB per Step
– Unity (0dB) Gain Setting via Serial Port
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DYNAMIC PERFORMANCE:
– Equivalent Input Noise with Z
S
= 150Ω
and Gain = 30dB: –123dBu
– Total Harmonic Distortion plus Noise
(THD+N) with Gain = 30dB: 0.0006%
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ZERO CROSSING DETECTION MINIMIZES
AUDIBLE ARTIFACTS WHEN GAIN
SWITCHING
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INTEGRATED DC SERVO MINIMIZES
OUTPUT OFFSET VOLTAGE
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COMMON-MODE SERVO IMPROVES CMRR
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FOUR-WIRE SERIAL CONTROL PORT
INTERFACE:
– Simple Interface to Microprocessor
or DSP Serial Ports
– Supports Daisy-Chaining of Multiple
PGA2505 Devices
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OVER-RANGE OUTPUT PIN PROVIDES
CLIPPING INDICATION
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FOUR GENERAL-PURPOSE
DIGITAL OUTPUT PINS
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±5V POWER SUPPLIES
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AVAILABLE IN AN SSOP-24 PACKAGE
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DESCRIPTION
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.
SoundPlus™
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.
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SoundPlus is a trademark of Texas Instruments Incorporated.
SPI is a trademark of Motorola, Inc..
All other trademarks are the property of their respective owners.
Copyright © 2009, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
TI [ TEXAS INSTRUMENTS ]
