Data Sheet
FEATURES
Easy to use
Rail-to-rail output swing
Input voltage range extends 150 mV below ground
(single supply)
Low power, 550 µA maximum quiescent current
Gain set with one external resistor
Gain range: 1 to 1000
High accuracy dc performance
0.10% gain error (G = 1)
0.35% gain error (G > 1)
Noise: 35 nV/√Hz RTI noise at 1 kHz
Optimal dynamic specifications
800 kHz bandwidth (G = 1)
20 µs settling time to 0.01% (G = 10)
Single and Dual-Supply, Rail-to-Rail,
Low Cost Instrumentation Amplifier
AD623
GENERAL DESCRIPTION
The
AD623
is an integrated, single- or dual-supply instrumentation
amplifier that delivers rail-to-rail output swing using supply
voltages from 2.7 V to 12 V. The
AD623
offers user flexibility by
allowing single gain set resistor programming and by conforming
to the 8-lead industry standard pinout configuration. With no
external resistor, the
AD623
is configured for unity gain (G = 1),
and with an external resistor, the
AD623
can be programmed for
gains of up to 1000.
The accuracy of the
AD623
is the result of increasing ac
common-mode rejection ratio (CMRR) coincident with
increasing gain. Line noise harmonics are rejected due to
constant CMRR up to 200 Hz. The
AD623
has a wide input
common-mode range and amplifies signals with common-
mode voltages as low as 150 mV below ground. The
AD623
maintains optimal performance with dual and single polarity
power supplies.
Table 1. Low Power Upgrades for the
AD623
Part No.
AD8235
AD8236
AD8237
AD8226
AD8227
AD8420
AD8422
AD8426
Total Supply Voltage, V
S
(V dc)
5.5
5.5
5.5
36
36
36
36
36
Typical Quiescent
Current, I
Q
(µA)
30
33
33
350
325
85
300
325 (per channel)
APPLICATIONS
Low power medical instrumentation
Transducer interfaces
Thermocouple amplifiers
Industrial process controls
Difference amplifiers
Low power data acquisition
FUNCTIONAL BLOCK DIAGRAM
2
–IN
V
DIFF
2
V
CM
V
DIFF
2
+IN
3
4
–V
S
A2
–
+
–
+
+V
S
7
A1
–R
G
R
G
1
8
+R
G
REF
00778-054
50kΩ
50kΩ
50kΩ
A3
50kΩ
6
OUTPUT
50kΩ
50kΩ
5
Figure 1.
Rev. G
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AD623
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 4
Single Supply ................................................................................. 4
Dual Supplies ................................................................................ 6
Specifications Common to Dual and Single Supplies ............. 8
Absolute Maximum Ratings............................................................ 9
ESD Caution .................................................................................. 9
Pin Configuration and Function Descriptions ........................... 10
Typical Performance Characteristics ........................................... 11
Theory of Operation ...................................................................... 23
Applications Information .............................................................. 24
Data Sheet
Basic Connection ....................................................................... 24
Gain Selection ............................................................................. 24
Reference Terminal .................................................................... 24
Input and Output Offset Voltage Error ................................... 24
Input Protection ......................................................................... 25
RF Interference ........................................................................... 25
Grounding ................................................................................... 26
Input Differential and Common-Mode Range vs. Supply and
Gain .............................................................................................. 28
Additional Information ............................................................. 29
Evaluation Board ............................................................................ 30
General Description ................................................................... 30
Outline Dimensions ....................................................................... 31
Ordering Guide .......................................................................... 32
REVISION HISTORY
9/2020—Rev. F to Rev. G
Changed AD623A to AD623ANZ, AD623ARZ and AD623B to
AD623BNZ, AD623BRZ .............................................. Throughout
Changes to General Description Section ...................................... 1
Changes to Figure 5 Caption, Figure 6 Caption, and Figure 8
Caption ............................................................................................. 10
Changes to Figure 10 Caption, Figure 11, Figure 12, Figure 13,
and Figure 14 ................................................................................... 12
Changes to Figure 15 to Figure 20 ................................................ 13
Changes to Figure 21 to Figure 26 ................................................ 14
Changes to Figure 27 to Figure 32 ................................................ 15
Changes to Figure 33 to Figure 38 ................................................ 16
Changes to Figure 39 to Figure 40 ................................................ 17
Added Figure 41 to Figure 44; Renumbered Sequentially ........ 17
Added Figure 45 to Figure 50........................................................ 18
Added Figure 51 to Figure 56........................................................ 19
Added Figure 57 to Figure 62........................................................ 20
Added Figure 63 to Figure 66........................................................ 21
Deleted Single-Supply Data Acquisition System Section and
Figure 53; Renumbered Sequentially ........................................... 21
Added Figure 67 to Figure 69........................................................ 22
Change to Figure 70 ....................................................................... 23
Changes to Basic Connection Section and Reference Terminal
Section .............................................................................................. 24
Changes to RF Interference Section ............................................ 25
Change to Figure 77 ....................................................................... 26
Changes to Figure 79 and Output Buffering Section ................. 27
Changes to Input Differential and Common-Mode Range vs.
Supply and Gain Section................................................................ 28
Changes to Ordering Guide .......................................................... 32
4/2018—Rev. E to Rev. F
Changes to Gain Error Parameter, Nonlinearity Parameter,
Offset Referred to the Input vs. Supply (PSR) Parameter, and
Output Swing Parameter, Table 2 ....................................................3
Changes to Gain Error Parameter and Offset Referred to the
Input vs. Supply (PSR) Parameter, Table 3 .....................................5
Changes to Current Noise Parameter, Table 4 ...............................7
Changes to Ordering Guide .......................................................... 26
6/2016—Rev. D to Rev. E
Changes to Features Section, General Description Section,
and Figure 1 ........................................................................................1
Deleted Connection Diagram Section............................................1
Added Functional Block Diagram Section and Table 1;
Renumbered Sequentially ................................................................1
Changes to Single Supply Section ...................................................3
Changes to Table 3.............................................................................6
Changed Both Dual and Single Supplies Section to
Specifications Common to Dual and Single Supplies Section ....7
Changes to Table 5.............................................................................8
Added Pin Configuration and Function Descriptions Section,
Figure 2, and Table 6; Renumbered Sequentially ..........................9
Changes to Figure 5 Caption, Figure 6 Caption, and
Figure 8 Caption ............................................................................. 10
Changes to Figure 17 Caption through Figure 20 Caption ...... 11
Changes to Figure 21 Caption through Figure 26 Caption ...... 12
Changes to Figure 27 Caption and Figure 28 Caption .............. 13
Changes to Theory of Operation Section.................................... 17
Changes to Basic Connection Section ......................................... 18
Changes to Input and Output Offset Voltage Error Section, and
Input Protection Section................................................................ 19
Rev. G | Page 2 of 32