Cirrus Logic CS5373A - Manual

Copyright  Cirrus Logic, Inc. 2010
(All Rights Reserved)
http://www.cirrus.com
CS5373A
Low-power, High-performance
ΔΣ
Modulator and Test DAC
Modulator Features
 Fourth-order
ΔΣ Architecture
• Clock-jitter-tolerant architecture
• Input signal bandwidth: DC to 2 kHz
• Max AC amplitude: 5 V
pp
differential
• Max DC amplitude: ± 2.5 V
dc
differential
 High Dynamic Range
• 127 dB SNR @ 215 Hz BW (2 ms sampling)
• 124 dB SNR @ 430 Hz BW (1 ms sampling)
 Low Total Harmonic Distortion
• -118 dB THD typical (0.000126%)
• -112 dB THD maximum (0.000251%)
 Low Power Consumption: 25 mW, 10 µW
Test DAC Features
 Digital
ΔΣ Input from CS5378 Digital Filter
 Selectable Differential Analog Outputs
• Precision output (OUT±) for electronics tests
• Buffered output (BUF±) for sensor tests
 Multiple AC and DC Operational Modes
• Output signal bandwidth: DC to 100 Hz
• Max AC amplitude: 5 V
pp
differential
• Max DC amplitude: + 2.5 V
dc
differential
 Selectable Attenuation to Match CS3301A/02A
• 1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64
 Outstanding Performance
• OUT AC: -115 dB THD typical, -112 dB maximum
• BUF AC: -105 dB THD typical, -95 dB maximum
• OUT DC: Differential VREF ± 10 mV typical
• BUF DC: Differential VREF ± 25 mV typical
 Low Power Consumption
• AC modes / DC modes: 40 mW / 25 mW
• Sleep mode / Power down: 2.5 mW / 600 µW
Common Features
 Extremely Small Footprint
• 28-pin SSOP package, 8 mm x 10 mm
 Bipolar Power Supply Configuration
• VA+ = +2.5 V; VA- = -2.5 V; VD = +3.3 V
Description
The CS5373A is a high-performance, fourth-order ΔΣ
modulator integrated with a
ΔΣ digital-to-analog convert-
er (DAC). When combined with a CS3301A/02A
differential amplifier and the CS5378 digital filter, a
small, low-power, self-testing, high-accuracy, single-
channel measurement system results.
The modulator has high dynamic range and low total har-
monic distortion with very low power consumption. It
converts differential analog input signals from the
CS3301A/02A amplifier to an oversampled serial bit
stream at 512 kbits per second. This oversampled bit
stream is then decimated by the CS5378 digital filter to a
24-bit output at the selected output word rate.
The test DAC operates in either AC or DC test modes.
AC test modes measure system dynamic performance
through THD and CMRR tests while DC test modes are
for gain calibration and pulse tests. It has two sets of dif-
ferential analog outputs, OUT and BUF, as dedicated
outputs for testing the electronics channel and for in-
circuit sensor tests. Output attenuation settings are
binary weighted and match the gain settings of the
CS3301A/02A differential amplifiers for full-scale testing
at all gain ranges.
ORDERING INFORMATION
See page 39 .
24-Bit
ΔΣ
Test DAC
Attenuator
1/1 to 1/64
Clock
Generator
VA+
MODE(0, 1, 2) ATT(0, 1, 2)
VD
VA-
VREF+ VREF-
GND
MCLK
MSYNC
24-Bit
ΔΣ
Modulator
OUT+
OUT-
BUF+
BUF-
TDATA
CAP+
CAP-
MDATA
MFLAG
INR+
INF+
INF-
INR-
OCT ‘10
DS703F2