AD629-EVAL Analog Devices Inc, AD629-EVAL Datasheet - Page 13

• Manufacturer Part Number: AD629-EVAL
• Description: BOARD EVAL COMMON MODE AD629
• Manufacturer: Analog Devices Inc
• Type: Amplifiers: OP Ampsr

Specifications of AD629-EVAL

• Design Resources: Measuring -48 V High-Side Current Using AD629, AD8603, AD780, and AD7453 (CN0100)
• Contents: Evaluation Board
• For Use With/related Products: AD629
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

ERROR BUDGET ANALYSIS EXAMPLE 2
This application is similar to the previous example except
that the sensed load current is from an amplifier with an ac
common-mode component of ±100 V (frequency = 500 Hz)
present on the shunt (see Figure 39). All other conditions are
the same as before. Note that the same kind of power-line
interference can happen as detailed in Example 1. However,
the ac common-mode component of 200 V p-p coming from
the shunt is much larger than the interference of 1 V p-p;
therefore, this interference component can be neglected.
Table 6. AD629 vs. INA117 AC Error Budget Example 2 (V
Error Source
ACCURACY, T
TEMPERATURE DRIFT (85°C)
RESOLUTION
Initial Gain Error
Offset Voltage
Gain
Offset Voltage
Noise, Typical, 0.01 Hz to 10 Hz, μV p-p
CMR, 60 Hz
Nonlinearity
AC CMR @ 500 Hz
A
= 25°C
AD629
(0.0005 × 10)/10 V × 10
(0.001 V/10 V) × 10
10 ppm/°C × 60°C
(20 μV/°C × 60°C) × 10
15 μV/10 V × 10
(141 × 10
(10
(141 × 10
-5
× 10 V)/10 V × 10
-6
-6
× 1 V)/10 V × 10
× 200 V)/10 V × 10
Rev. B | Page 13 of 16
CM
6
= ±100 V @ 500 Hz)
6
6
6
/10 V
6
6
SHUNT
6
CURRENT
1Ω
OUTPUT
Figure 39. Error Budget Analysis Example 2: V
10 AMPS
±100V AC CM
TO GROUND
INA117
(0.0005 × 10)/10 V × 10
(0.002 V/10 V) × 10
Total Accuracy Error
10 ppm/°C × 60°C
(40 μV/°C × 60°C) × 10
Total Drift Error
25 μV/10 V × 10
(500 × 10
(10
(500 × 10
Total Resolution Error
Total Error
POWER LINE
-5
60Hz
× 10 V)/10 V × 10
V
-6
-6
CM
× 1 V)/10 V × 10
× 200 V)/10 V × 10
= ±100 V at 500 Hz, R
–V
6
S
REF (–)
6
0.1µF
–IN
+IN
6
6
/10 V
6
1
2
3
4
NC = NO CONNECT
21.1kΩ
380kΩ
380kΩ
6
6
SHUNT
AD629
380kΩ
20kΩ
=1 Ω
IN
AD629
500
100
600
600
120
720
2
14
10
2820
2846
4166
= 10 V Full-Scale,
Error, ppm of FS
8
7
6
5
NC
REF (+)
AD629
INA117
500
200
700
600
240
840
3
50
10
10,000
10,063
11,603
0.1µF
V
OUT
+V
S