CS5373A
Low-power, High-performance Modulator and Test DAC
Modulator Features Description
The CS5373A is a high-performance, fourth-order
Fourth-order Architecture
modulator integrated with a digital-to-analog convert-
Clock-jitter-tolerant architecture
er (DAC). When combined with a CS3301A/02A
Input signal bandwidth: DC to 2 kHz
differential amplifier and the CS5378 digital filter, a
Max AC amplitude: 5 V differential
pp
small, low-power, self-testing, high-accuracy, single-
Max DC amplitude: 2.5 V differential
dc
channel measurement system results.
High Dynamic Range
The modulator has high dynamic range and low total har-
127 dB SNR @ 215 Hz BW (2 ms sampling)
monic distortion with very low power consumption. It
124 dB SNR @ 430 Hz BW (1 ms sampling)
converts differential analog input signals from the
Low Total Harmonic Distortion
CS3301A/02A amplifier to an oversampled serial bit
-118 dB THD typical (0.000126%)
stream at 512 kbits per second. This oversampled bit
-112 dB THD maximum (0.000251%)
stream is then decimated by the CS5378 digital filter to a
Low Power Consumption: 25 mW, 10 W 24-bit output at the selected output word rate.
The test DAC operates in either AC or DC test modes.
Test DAC Features
AC test modes measure system dynamic performance
through THD and CMRR tests while DC test modes are
Digital Input from CS5378 Digital Filter
for gain calibration and pulse tests. It has two sets of dif-
Selectable Differential Analog Outputs
ferential analog outputs, OUT and BUF, as dedicated
Precision output (OUT) for electronics tests
outputs for testing the electronics channel and for in-
Buffered output (BUF) for sensor tests
circuit sensor tests. Output attenuation settings are
Multiple AC and DC Operational Modes
binary weighted and match the gain settings of the
Output signal bandwidth: DC to 100 Hz
CS3301A/02A differential amplifiers for full-scale testing
Max AC amplitude: 5 V differential
at all gain ranges.
pp
Max DC amplitude: + 2.5 V differential
dc
ORDERING INFORMATION
Selectable Attenuation to Match CS3301A/02A
See page 39.
1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64
Outstanding Performance
VA+ VREF+ VREF- VD
OUT AC: -115 dB THD typical, -112 dB maximum
BUF AC: -105 dB THD typical, -95 dB maximum
INR+ MDATA
OUT DC: Differential VREF 10 mV typical
INF+ 24-Bit MFLAG
BUF DC: Differential VREF 25 mV typical
INF- Modulator MCLK
Clock
Low Power Consumption
Generator
INR- MSYNC
AC modes / DC modes: 40 mW / 25 mW
Sleep mode / Power down: 2.5 mW / 600 W
OUT+
TDATA
OUT- 24-Bit
Attenuator
Common Features
1/1 to 1/64
BUF+ CAP+
Test DAC
Extremely Small Footprint
BUF- CAP-
28-pin SSOP package, 8 mm x 10 mm
Bipolar Power Supply Configuration
VA- ATT(0, 1, 2) MODE(0, 1, 2) GND
VA+ = +2.5 V; VA- = -2.5 V; VD = +3.3 V
Copyright Cirrus Logic, Inc. 2010
OCT 10
CS5373A
TABLE OF CONTENTS
1. CHARACTERISTICS AND SPECIFICATIONS ........................................................................ 4
SPECIFIED OPERATING CONDITIONS ................................................................................. 4
TEMPERATURE CONDITIONS ............................................................................................... 5
ABSOLUTE MAXIMUM RATINGS ........................................................................................... 5
ANALOG INPUT CHARACTERISTICS ................................................................................... 6
ANALOG OUTPUT CHARACTERISTICS ............................................................................... 7
MODULATOR CHARACTERISTICS........................................................................................ 8
PERFORMANCE PLOTS ......................................................................................................... 9
DAC AC DIFFERENTIAL MODES 1, 2, 3............................................................................... 10
DAC AC DIFFERENTIAL MODES 1, 2, 3 (CONT.) ............................................................... 11
DIGITAL CHARACTERISTICS .............................................................................................. 15
DIGITAL CHARACTERISTICS (CONT.) ............................................................................... 16
DIGITAL CHARACTERISTICS (CONT.) ............................................................................ 17
POWER SUPPLY CHARACTERISTICS ................................................................................ 18
2. GENERAL DESCRIPTION ..................................................................................................... 19
2.1 Delta-Sigma Modulator ....................................................................................................19
2.2 Digital-to-Analog Converter .............................................................................................. 19
3. SYSTEM DIAGRAM ............................................................................................................ 20
4. POWER MODES ..................................................................................................................... 21
4.1 Power Down ..................................................................................................................... 21
4.2 Sleep Mode ...................................................................................................................... 21
4.3 Modulator Mode ............................................................................................................... 21
4.4 AC Test Modes ................................................................................................................ 21
4.5 DC Test Modes ................................................................................................................ 21
5. OPERATIONAL MODES ........................................................................................................ 22
5.1 Modulator Mode ............................................................................................................... 22
5.1.1 Modulator Ones Density ..................................................................................... 22
5.1.2 Modulator Decimated Output .............................................................................. 22
5.1.3 Modulator Synchronization .................................................................................. 22
5.1.4 Modulator Idle Tones .......................................................................................... 23
5.1.5 Modulator Stability ............................................................................................... 23
5.2 AC Test Modes ................................................................................................................ 23
5.2.1 AC Differential ..................................................................................................... 23
5.2.2 AC Common Mode .............................................................................................. 24
5.2.3 DAC Stability ....................................................................................................... 24
5.3 DC Test Modes ................................................................................................................ 24
5.3.1 DC Common Mode ............................................................................................. 24
5.3.2 DC Differential ..................................................................................................... 25
5.4 Sleep Mode ...................................................................................................................... 25
6. DIGITAL SIGNALS ................................................................................................................. 26
6.1 MCLK Connection ............................................................................................................26
6.2 MSYNC Connection ......................................................................................................... 26
6.3 MDATA Connection ......................................................................................................... 27
6.4 MFLAG Connection ......................................................................................................... 27
6.5 TDATA Connection .......................................................................................................... 27
6.6 GPIO Connections ...........................................................................................................27
7. ANALOG SIGNALS ................................................................................................................ 28
7.1 INR, INF Modulator Inputs ........................................................................................... 28
7.1.1 Modulator Input Impedance ................................................................................ 28
7.1.2 Modulator Anti-alias Filter ................................................................................... 28
7.2 DAC Output Attenuation .................................................................................................. 29
7.3 DAC OUT Precision Output ........................................................................................... 29
7.4 DAC BUF Buffered Output ............................................................................................. 30
2 DS703F2