CS3302
2. GENERAL DESCRIPTION
The CS3302 is a high-impedance, low-noise 2.1
Analog Signals
CMOS differential input, differential output ampli-
fier for precision analog signals between DC and
2 kHz. It has multiplexed inputs, rough/fine charge
outputs, and programmable gains of x1, x2, x4, x8,
x16, x32, and x64.
2.1.1
Analog Inputs
The amplifier analog inputs are designed for high-
impedance differential sensors. Input multiplexing
simplifies system connections by providing sepa-
rate inputs for a sensor and test DAC (INA, INB) as
well as an internal termination for noise tests. The
MUX0, MUX1 digital pins determine which multi-
plexed input is connected to the amplifier.
The amplifier’s performance makes it ideal for
low-frequency, high-dynamic-range applications
requiring low distortion and minimal power con-
sumption. It’s optimized for use in acquisition sys-
tems designed around the CS5371/72 single/dual
∆Σ modulators and the CS5376A quad digital fil-
ter. Figure 3 shows the system-level architecture
of a 4-channel acquisition system using four
CS3302, two CS5372, one CS4373A, and one
CS5376A.
2.1.2
Analog Outputs
The amplifier analog outputs are separated into
rough charge / fine charge signals to easily connect
to the CS5371/72 inputs. Each output also includes
a series resistor, requiring only two differential ca-
pacitors to create the CS5371/72 input anti-alias
filter.
Geophone
CS3301
or
CS3302
M
U
X
Hydrophone
Sensor
CS5371
CS5372
AMP
System Telemetry
∆Σ
Modulator
Geophone
or
Hydrophone
Sensor
µController
CS3301
CS3302
or
M
U
X
Configuration
EEPROM
AMP
CS5376A
Digital Filter
Geophone
or
Hydrophone
Sensor
CS3301
CS3302
M
U
X
CS5371
CS5372
AMP
AMP
Communication
Interface
∆Σ
Geophone
or
Hydrophone
Sensor
Modulator
CS3301
CS3302
M
U
X
CS4373A
Test
DAC
Switch
Switch
MUX
MUX
Figure 3. System Architecture
10
DS596F3
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