Cirrus Logic CS3302A - Manual

Copyright
© Cirrus Logic, Inc. 2007
(All Rights Reserved)
Preliminary Product Information
This document contains information for a new product.
Cirrus Logic reserves the right to modify this product without notice.
http://www.cirrus.com
High-Z, Programmable Gain, Differential Amplifier
Features & Description
z Signal Bandwidth: DC to 2 kHz
z Selectable Gain: x1, x2, x4, x8, x16, x32, x64
z Differential Inputs, Differential Outputs
• Multiplexed inputs: INA, INB, 800 Ω termination
• Rough / fine charge outputs for CS5371A / 72A / 73A
• Max signal amplitude: 5 V
pp
differential
• Ultra-low input bias: < 1 pA
z Excellent Noise Performance
• 1 µV
p-p
between 0.1 Hz and 10 Hz
• 8.5 nV/ √Hz from 200 Hz to 2 kHz
z Low Total Harmonic Distortion
• -118 dB THD typical (0.000126%)
• -112 dB THD maximum (0.000251%)
z Low Power Consumption
• Normal operation: 5 mA
• Power down: 10
µA
z Dual Power Supply Configuration
• VA+ = +2.5 V; VA- = -2.5 V; VD = +3.3 V
Description
The CS3302A is a high input-impedance, differential in-
put, differential output amplifier with programmable
gain, optimized for amplifying signals from high-imped-
ance sensors such as hydrophones. The gain settings
are binary weighted (x1, x2, x4, x8, x16, x32, x64) and
are selected using simple pin settings. Two sets of ex-
ternal inputs, INA and INB, simplify system design as
inputs from a sensor and test DAC. An internal 800
Ω
termination can also be selected for noise tests.
Amplifier input impedance is very high, requiring less
than 1 pA of input current. Noise performance is very
good at 1
µ V
p-p
between 0.1 Hz and 10 Hz, and a noise
density of 8.5 nV/
√Hz over the 200 Hz to 2 kHz band-
width. Distortion performance is also extremely good,
typically -118 dB THD. Low input current, low noise, and
low total harmonic distortion make this amplifier ideal for
high-impedance differential sensors requiring maximum
dynamic range.
ORDERING INFORMATION
See page 15 .
INA+
INB+
MUX0
MUX1
INB-
INA-
VA+
VA-
VD
GND
GUARD
OUTR+
OUTF+
GAIN0
GAIN1
GAIN2
OUTF-
OUTR-
PWDN
+
-
-
+
40
0
Ω
40
0
Ω
NOV '07
DS765PP1
CS3302A