AD636

Data Sheet

Rev. E | Page 2 of 16

TABLE OF CONTENTS

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

Functional Block Diagram .............................................................. 1

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

Revision History ............................................................................... 2

Specifications..................................................................................... 3

Absolute Maximum Ratings............................................................ 5

ESD Caution.................................................................................. 5

Pin Configurations and Function Descriptions ........................... 6

Typical Performance Characteristics ............................................. 7

Theory of Operation ........................................................................ 8

RMS Measurements ..................................................................... 8

The AD636 Buffer Amplifier ...................................................... 8

Frequency Response..................................................................... 9

AC Measurement Accuracy and Crest Factor (CF)................. 9

Applications..................................................................................... 10

Standard Connection................................................................. 10

Optional Trims for High Accuracy.......................................... 10

Single-Supply Connection ........................................................ 10

Choosing the Averaging Time Constant................................. 11

A Complete AC Digital Voltmeter........................................... 12

A Low Power, High Input, Impedance dB Meter....................... 12

Circuit Description ................................................................ 12

Performance Data .................................................................. 12

Frequency Response ±3 dBm ............................................... 13

Calibration .............................................................................. 13

Outline Dimensions....................................................................... 14

Ordering Guide .......................................................................... 14

REVISION HISTORY

5/13—Rev. D to Rev. E

Reorganized Layout............................................................Universal

Changes to Figure 1...........................................................................1

Change to Table 1 ..............................................................................4

Added Typical Performance Characteristics Section ...................7

Added Theory of Operation Section; Changes to Figure 7 and

Figure 8 ...............................................................................................8

Changed Applying the AD636 Section to Applications Section;

Changes to Figure 9, Figure 10, and Single-Supply Connection

Section...............................................................................................10

Changes to Figure 11.......................................................................11

Changes to Figure 13 and A Complete AC Digital Voltmeter

Section...............................................................................................12

Changes to Figure 17 and Figure 18..............................................13

Changes to Ordering Guide ...........................................................14

11/06—Rev. C to Rev. D

Changes to General Description .....................................................1

Changes to Table 1.............................................................................3

Changes to Ordering Guide.......................................................... 13

1/06—Rev B to Rev. C

Updated Format..................................................................Universal

Changes to Figure 1 and General Description ..............................1

Deleted Metallization Photograph ..................................................3

Added Pin Configuration and Function Description Section ....6

Updated Outline Dimensions....................................................... 14

Changes to Ordering Guide.......................................................... 14

8/99—Rev A to Rev. B