CS5532-BSZR;CS5534-BSZR;CDB5532U;中文规格书,Datasheet资料

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Copyright © Cirrus Logic, Inc. 2008(All Rights Reserved)

http://www.cirrus.comCS5532/34-BS

24-bit ∆Σ ADCs with Ultra-low-noise PGIAFeatures

󰂉Chopper-stabilized PGIA (Programmable Gain Instrumentation Amplifier, 1x to 64x)–6 nV/√Hz @ 0.1 Hz (No 1/f noise) at 64x–1200pA Input Current with Gains >1

󰂉Delta-sigma Analog-to-digital Converter–Linearity Error: 0.0007% FS–Noise-free Resolution: Up to 23 bits

󰂉Two- or Four-channel Differential MUX

󰂉Scalable Input Span via Calibration –±5 mV to differential ±2.5V

󰂉Scalable VREF Input: Up to Analog Supply

󰂉Simple Three-wire Serial Interface–SPI™ and Microwire™ Compatible–Schmitt Trigger on Serial Clock (SCLK)

󰂉R/W Calibration Registers Per Channel

󰂉Selectable Word Rates: 6.25 to 3,840 Sps

󰂉Selectable 50 or 60 Hz Rejection

󰂉Power Supply Configurations–VA+ = +5 V; VA- = 0 V; VD+ = +3 V to +5 V–VA+ = +2.5 V; VA- = -2.5 V; VD+ = +3 V to +5 V–VA+ = +3 V; VA- = -3 V; VD+ = +3 VGeneral Description

The CS5532/34 are highly integrated ∆Σ Analog-to-Digi-tal Converters (ADCs) which use charge-balancetechniques to achieve 24-bit performance. The ADCsare optimized for measuring low-level unipolar or bipolarsignals in weigh scale, process control, scientific, andmedical applications.

To accommodate these applications, the ADCs come aseither two-channel (CS5532) or four-channel (CS5534)devices and include a very low-noise, chopper-stabilizedinstrumentation amplifier (6 nV/√Hz @ 0.1 Hz) with se-lectable gains of 1×, 2×, 4×, 8×, 16×, 32×, and 64×.These ADCs also include a fourth-order ∆Σ modulatorfollowed by a digital filter which provides twenty selectableoutput word rates of 6.25, 7.5, 12.5, 15, 25, 30, 50, 60, 100,120, 200, 240, 400, 480, 800, 960, 1600, 1920, 3200, and3840 Sps (MCLK=4.9152MHz).

To ease communication between the ADCs and a micro-controller, the converters include a simple three-wire se-rial interface which is SPI™ and Microwire™ compatiblewith a Schmitt-trigger input on the serial clock (SCLK).

High dynamic range, programmable output rates, andflexible power supply options makes these ADCs idealsolutions for weigh scale and process controlapplications.

ORDERING INFORMATIONSee page47

VA+C1C2VREF+VREF-VD+

DIFFERENTIAL4TH ORDER ∆ΣMODULATORPGIA1,2,4,8,16PROGRAMMABLESINC FIR FILTER

MUX(CS5534SHOWN)AIN1+AIN1-AIN2+AIN2-AIN3+AIN3-AIN4+AIN4-SERIALINTERFACE

LATCHCLOCKGENERATORCALIBRATIONSRAM/CONTROLLOGIC

DGNDCSSDISDOSCLK

OSC2OSC1A1A0/GUARDVA-32,64

OCT ‘08DS755F3

http://oneic.com/CS5532/34-BS

2DS755F3TABLE OF CONTENTS

1.CHARACTERISTICS AND SPECIFICATIONS ..........................................................4ANALOG CHARACTERISTICS..........................................................................4TYPICAL RMS NOISE (NV)...............................................................................7TYPICAL NOISE-FREE RESOLUTION(BITS)...................................................75 V DIGITAL CHARACTERISTICS....................................................................83 V DIGITAL CHARACTERISTICS....................................................................8DYNAMIC CHARACTERISTICS........................................................................9ABSOLUTE MAXIMUM RATINGS.....................................................................9SWITCHING CHARACTERISTICS..................................................................102.GENERAL DESCRIPTION .......................................................................................122.1.Analog Input ....................................................................................................122.1.1. Analog Input Span ....................................................................................132.1.2. Multiplexed Settling Limitations ............................................................132.1.3. Voltage Noise Density Performance .....................................................132.1.4. No Offset DAC ......................................................................................142.2.Overview of ADC Register Structure and Operating Modes ............................142.2.1. System Initialization ..............................................................................152.2.2. Serial Port Interface ..............................................................................222.2.3. Reading/Writing On-Chip Registers ......................................................232.3.Configuration Register .....................................................................................232.3.1. Power Consumption .............................................................................232.3.2. System Reset Sequence ......................................................................232.3.3. Input Short ............................................................................................242.3.4. Guard Signal .........................................................................................242.3.5. Voltage Reference Select .....................................................................242.3.6. Output Latch Pins .................................................................................242.3.7. Offset and Gain Select ..........................................................................252.3.8. Filter Rate Select ..................................................................................252.4.Setting up the CSRs for a Measurement .........................................................272.5.Calibration ........................................................................................................302.5.1. Calibration Registers ............................................................................302.5.2. Performing Calibrations ........................................................................312.5.3. Self Calibration .....................................................................................312.5.4. System Calibration ................................................................................322.5.5. Calibration Tips .....................................................................................322.5.6. Limitations in Calibration Range ...........................................................332.6.Performing Conversions ..................................................................................332.6.1. Single Conversion Mode .......................................................................332.6.2. Continuous Conversion Mode ..............................................................342.6.3. Examples of Using CSRs to Perform Conversions and Calibrations ....352.7.Using Multiple ADCs Synchronously ...............................................................362.8.Conversion Output Coding ..............................................................................362.9.Digital Filter ......................................................................................................382.10.Clock Generator ...............................................................................................392.11.Power Supply Arrangements ...........................................................................392.12.Getting Started ................................................................................................432.13.PCB Layout .....................................................................................................433.PIN DESCRIPTIONS ...............................................................................................444.SPECIFICATION DEFINITIONS ...............................................................................465.ORDERING INFORMATION .....................................................................................476.ENVIRONMENTAL, MANUFACTURING, & HANDLING INFORMATION ..............477.PACKAGE DRAWINGS ...........................................................................................48