ad8205yc-pt Analog Devices, Inc., ad8205yc-pt Datasheet - Page 10

• Manufacturer Part Number: ad8205yc-pt
• Description: Single-supply 42 V System Difference Amplifier
• Manufacturer: Analog Devices, Inc.

AD8205
EXTERNAL REFERENCE OUTPUT
Tying both pins together and to a reference produces an output
at the reference voltage when there is no differential input (see
Figure 16). The output moves down from the reference voltage
when the input is negative relative to the −IN pin and up when
the input is positive relative to the −IN pin.
SPLITTING THE SUPPLY
By tying one reference pin to V+ and the other to the ground
pin, the output is set at half of the supply when there is no
differential input (see Figure 17). The benefit is that no external
reference is required to offset the output for bidirectional
current measurement. This creates a midscale offset that is
ratiometric to the supply, which means that if the supply increases
or decreases, the output remains at half the supply. For example, if
the supply is 5.0 V, the output is at half scale or 2.5 V. If the supply
increases by 10% (to 5.5 V), the output goes to 2.75 V.
NC = NO CONNECT
+IN
–IN
NC
AD8205
Figure 16. External Reference Output
GND
V+
V
V
REF
REF
OUT
1
2
2.5V VOLTAGE
REFERENCE
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SPLITTING AN EXTERNAL REFERENCE
In this case, an external reference is divided by 2 with an
accuracy of approximately 0.5% by connecting one V
ground and the other V
NC = NO CONNECT
+IN
–IN
NC
AD8205
NC = NO CONNECT
+IN
–IN
NC
AD8205
Figure 18. Split External Reference
Figure 17. Split Supply
REF
GND
pin to the reference (see Figure 18).
V+
GND
V+
V
V
REF
REF
OUT
1
2
V
V
REF
REF
OUT
1
2
5V
VOLTAGE
REFERENCE
REF
pin to