Analog Devices AD8224-EVALZ User manual

Precision Instrumentation Amplifier
Evaluation Board
AD8224-EVALZ
Rev. 0
Evaluation boards are only intended for device evaluation and not for production purposes.
Evaluation boards as supplied “as is” and without warranties of any kind, express, implied, or
statutory including, but not limited to, any implied warranty of merchantability or fitness for a
particular purpose. No license is granted by implication or otherwise under any patents or other
intellectual property by application or use of evaluation boards. Information furnished by Analog
Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog
Devices for its use, nor for any infringements of patents or other rights of third parties that may result
from its use. Analog Devices reserves the right to change devices or specifications at any time
without notice. Trademarks and registered trademarks are the property of their respective owners.
Evaluation boards are not authorized to be used in life support devices or systems.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2007 Analog Devices, Inc. All rights reserved.
FEATURES
Two AD8224 circuits
Dual channel
Differential output
Easy to connect screw terminals
Decoupled supply lines
Pads for RFI filtering
GENERAL DESCRIPTION
The AD8224-EVALZ has two AD8224 instrumentation
amplifier circuits: one circuit is configured for dual-channel
operation, and the other is configured for single-channel,
differential output operation. The inputs, outputs, references,
and supplies are routed to screw terminals for easy connectivity.
The PCB board has four layers. The top and bottom layers are
used for routing, and the two internal layers are ground planes.
The ground plane was removed underneath the RGresistors.
This is a precaution against any capacitance mismatch at the
RGx pins that may affect ac CMRR.
AD8224 EVALUATION BOARD
06687-003
Figure 1.

AD8224-EVALZ
Rev. 0 | Page 2 of 4
EVALUATION BOARD HARDWARE
JUMPER SETTINGS
Table 1.
Jumper Purpose Default
J1A, J1B, J11 Connect inputs together Unconnected
J2A, J2B, J12, J13 Connect reference pins
to ground
Connected
In the default factory setting, the reference pins of the AD8224
are connected to GND through J2A, J2B, J12, and J13. These
jumpers also connect to W2A:REF1, W2B:REF2, W13:REF2, and
W13:+IN2. Therefore, in the shipping configuration, W2A:REF1,
W2B:REF2, W13:REF2, and W13:+IN2 are connected to GND.
To disconnect the terminal from GND, remove the correspond-
ing jumper.
QUICK START
The quick start feature assumes that the jumpers are in their
default factory positions.
To begin:
1. Connect a ground lead to GND.
2. Connect a +15 V supply to +VS.
3. Connect a −15 V supply to −Vs.
4. Ground −IN1.
5. Connect a 1 V p-p, 1 kHz source signal to +IN1. A replica
of the signal should now appear at OUT1.
SETTING THE GAIN
The gain setting resistors are R1A and R1B for the dual-channel
part and R11A for the differential output part. The pads are
sized for 0603-sized resistors, although 0402 and 0805 sizes can
also be used.
Table 2.
Channel Component
Dual Channel A R1A
Dual Channel B R1B
Differential Output Channel R11A
EMI FILTERING
The board comes with 0603 component pads for an EMI filter.
These components are shown in Table 3 .
Table 3.
Channel Component
Dual Channel A R3A, R2A, C1A, C2A, C3A
Dual Channel B R3B, R2B, C1B, C2B, C3B
Differential Output Channel R13, R12, C11, C12, C13
The board, as shipped, does not contain EMI filtering. The
resistors pads are populated with 0 Ω resistors, and the
capacitors are not populated.
See the AD8224 data sheet for more information on EMI
filtering.

AD8224-EVALZ
Rev. 0 | Page 3 of 4
EVALUATION BOARD SCHEMATICS
–V
S
+V
S
–V
S
+V
S
OUT1 OUT2
REF1 REF2
REF_A
REF_B
W2A
J2A J2B
W2B
–IN1
+IN1
–IN2
+IN2
W1A
J1A
AD8224
DUAL
*NOT POPULATED
R3A
0Ω
C2A*
C3A*
R1A*
C1A*
C4
0.1µF
R2A
0Ω
REF_A REF_B
R2B
0Ω
C2B*
R1B*
C3B*
C1B*
R3B
0Ω
J1B
W1B
C5
0.1µF
06687-001
13141516
1
2
3
4
5 6 7 8
9
10
11
12
Figure 2. AD8224 Evaluation Board Schematic—AD8224 Dual Channel
W6 W5
AD8224
DIFF OUT
W13
J12
J13
GND1 GND2 GND3 GND4
–V
S
+V
S
+V
S
–V
S
C8
10µF
C7
10µF
+
+
+V
S
–V
S
R11B*
C15
0.1µF
13141516
1
2
3
4
5 6 7 8
9
10
11
12
+V
S
–IN1
+IN1
+IN2
REF2
W11
J11
–V
S
R11A*
R13
0Ω
C12*
C13*
C11*
C14
0.1µF
R12
0Ω
–
OUT
+OUT
W12
C10
100pF
R10
10kΩ
*NOT POPULATED
06687-002
Figure 3. AD8224 Evaluation Board Schematic—AD8224 Differential Output

AD8224-EVALZ
Rev. 0 | Page 4 of 4
ORDERING INFORMATION
ORDERING GUIDE
Model Description
AD8224-EVALZ1Evaluation Board
1Z = RoHS Compliant Part.
ESD CAUTION
©2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
EB06687-0-3/07(0)