Datasheet

INA322
13
SBOS174B
FIGURE 9. Simplified ECG Circuit for Medical Applications.
APPLICATION CIRCUITS
Medical ECG Applications
Figure 9 shows the INA322 configured to serve as a low-
cost ECG amplifier, suitable for moderate accuracy heart-
rate applications such as fitness equipment. The input sig-
nals are obtained from the left and right arms of the patient.
The common-mode voltage is set by two 2MΩ resistors.
This potential through a buffer, provides optional right leg
drive. Filtering can be modified to suit application needs by
changing the capacitor value of the output filter.
Low-Power, Single-Supply Data Acquisition
Systems
Refer to Figure 5 to see the INA322 configured to drive an
ADS7818. Functioning at frequencies of up to 500kHz, the
INA322 is ideal for low-power data acquisition.
OPA336
OPA336
OPA336
Right Arm
Left Arm
1MΩ
REF
1MΩ
1MΩ
10kΩ
10kΩ
2kΩ
2kΩ
1.6nF
0.1µF
100kΩ
100kΩ
+5V
V
R
V
R
V
R
= +2.5V
2MΩ
2MΩ
Right
Leg
INA322
5
3
2
8
7
6
4
1
V+
Shutdown
RG
V
IN
–
V–
V
IN
+
V
OUT PUT