Single-Supply 42 V System
Difference Amplifier

AD8205


Rev. 0
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FEATURES
Ideal for current shunt applications
High common-mode voltage range
−2 V to +65 V operating
−5 V to +68 V survival
Gain = 50
Wide operating temperature range
Die: −40°C to +150°C
8-lead SOIC: −40°C to +125°C
Adjustable offset
Available in SOIC and die form
EXCELLENT AC AND DC PERFORMANCE
15 µV/°C offset drift
30 ppm/°C gain drift
80 dB CMRR dc to 20 kHz
APPLICATIONS
High-side current sensing in:
Motor controls
Transmission controls
Diesel injection controls
Engine management
Suspension controls
Vehicle dynamic controls
DC-to-dc converters
FUNCTIONAL BLOCK DIAGRAM
04315-0-001
AD8205
8
1
4
2
3
7
5
6
+IN
–IN
NC
NC = NO CONNECT
GND
V+
OUT
V
REF
1
V
REF
2

Figure 1.

GENERAL DESCRIPTION
The AD8205 is a single-supply difference amplifier for amplify-
ing small differential voltages in the presence of large common-
mode voltages. The operating input common-mode voltage
range extends from −2 V to +65 V. The typical single-supply
voltage is 5 V.
The AD8205 is offered in die and packaged form. The operating
temperature range for the die is 25°C higher (up to 150°C) than
the packaged part to enable the user to apply the AD8205 in
high temperature applications.
Excellent dc performance over temperature keeps errors in the
measurement loop to a minimum. Offset drift is typically less
than 15 µV/°C, and gain drift is typically below 30 ppm/°C.
The output offset can be adjusted from 0.05 V to 4.8 V with a
5 V supply by using the VREF1 and VREF2 pins. With VREF1 at-
tached to the V+ pin, and VREF2 attached to the GND pin, the
output is set at half scale. Attaching both pins to GND causes
the output to be unipolar, starting near ground. Attaching both
pins to V+ causes the output to be unipolar starting near V+.
Other offsets can be obtained by applying an external voltage to
the VREF1 and VREF2 pins.