Data Sheet

ADA4945-1

analog.com

Rev. A

3 of 57

TABLE OF CONTENTS

Features......................................................................................................................................................................................................1

Applications ...............................................................................................................................................................................................1

General Description...................................................................................................................................................................................1

FUNCTIONAL BLOCK DIAGRAM .................................................................................................................................................................2

Revision History .........................................................................................................................................................................................4

Specifications.............................................................................................................................................................................................5

Absolute Maximum Ratings ....................................................................................................................................................................21

Thermal Resistance.............................................................................................................................................................................21

Maximum Power Dissipation..............................................................................................................................................................21

ESD Caution.........................................................................................................................................................................................22

Pin Configurations and Function Descriptions......................................................................................................................................23

Typical Performance Characteristics (FULL POWER MODE).................................................................................................................24

Typical Performance Characteristics (LOW POWER MODE)..................................................................................................................32

Test Circuits..............................................................................................................................................................................................40

TERMINOLOGY .........................................................................................................................................................................................41

Differential Voltage .............................................................................................................................................................................41

Common-Mode Voltage (CMV) ...........................................................................................................................................................41

Common-Mode Offset Voltage ...........................................................................................................................................................41

Differential VOS, Differential CMRR, and VOCM CMRR ...........................................................................................................................41

Balance ................................................................................................................................................................................................42

Theory of Operation ................................................................................................................................................................................43

Fully Differential and Common-Mode Signal Paths..........................................................................................................................43

Output Voltage Clamp ........................................................................................................................................................................44

Power Modes .......................................................................................................................................................................................45

Applications Information ........................................................................................................................................................................46

Analyzing an Application Circuit ........................................................................................................................................................46

Setting the Closed-Loop Gain.............................................................................................................................................................46

Estimating the Output Noise Voltage ................................................................................................................................................46

Impact of Mismatches in the Feedback Networks ............................................................................................................................47

Calculating the Input Impedance of an Application Circuit .............................................................................................................47

Terminating a Single-Ended Input.....................................................................................................................................................48

Input Common-Mode Voltage Range.................................................................................................................................................50

Input and Output Capacitive AC Coupling.........................................................................................................................................50

Setting the Output Common-Mode Voltage......................................................................................................................................50