CS5521/22/23/24/28

2

DS317F2

TABLE OF CONTENTS

1. CHARACTERISTICS AND SPECIFICATIONS ........................................................................ 5

ANALOG CHARACTERISTICS ................................................................................................ 5

TYPICAL RMS NOISE, CS5521/23.......................................................................................... 7

TYPICAL NOISE FREE RESOLUTION (BITS), CS5521/23 .................................................... 7

TYPICAL RMS NOISE, CS5522/24/28..................................................................................... 8

TYPICAL NOISE FREE RESOLUTION (BITS), CS5522/24/28 ............................................... 8

5 V DIGITAL CHARACTERISTICS........................................................................................... 9

3 V DIGITAL CHARACTERISTICS........................................................................................... 9

DYNAMIC CHARACTERISTICS ............................................................................................ 10

RECOMMENDED OPERATING CONDITIONS ..................................................................... 10

ABSOLUTE MAXIMUM RATINGS ......................................................................................... 10

SWITCHING CHARACTERISTICS ........................................................................................ 11

2. GENERAL DESCRIPTION ..................................................................................................... 13

2.1 Analog Input ..................................................................................................................... 13

2.1.1 Instrumentation Amplifier ......................................................................................... 14

2.1.2 Coarse/Fine Charge Buffers ............................................................................... 14

2.1.3 Analog Input Span Considerations .......................................................................... 15

2.1.4 Measuring Voltages Higher than 5 V .................................................................. 15

2.1.5 Voltage Reference .............................................................................................. 16

2.2 Overview of ADC Register Structure and Operating Modes ............................................ 16

2.2.1 System Initialization ............................................................................................ 18

2.2.2 Serial Port Initialization Sequence ...................................................................... 18

2.2.3 Command Register Quick Reference

............................................................... 19

2.2.4 Command Register Descriptions ........................................................................ 20

2.2.5 Serial Port Interface ............................................................................................ 25

2.2.6 Reading/Writing the Offset, Gain, and Configuration Registers .......................... 26

2.2.7 Reading/Writing the Channel-Setup Registers ................................................... 26

2.2.7.1 Latch Outputs ...................................................................................... 28

2.2.7.2 Channel Select Bits ............................................................................. 28

2.2.7.3 Output Word Rate Selection ............................................................... 28

2.2.7.4 Gain Bits .............................................................................................. 28

2.2.7.5 Unipolar/Bipolar Bit ............................................................................. 28

2.2.8 Configuration Register ........................................................................................ 28

2.2.8.1 Chop Frequency Select ....................................................................... 28

2.2.8.2 Conversion/Calibration Control Bits .................................................... 28

2.2.8.3 Power Consumption Control Bits ........................................................ 28

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