High Voltage,
Precision Difference Amplifier
AD8209
FUNCTIONAL BLOCK DIAGRAM
FEATURES
V
S
A1 A2
8000 V HBM ESD
AEC-Q100 qualified
EMI filters included
High common-mode voltage range
−2 V to +45 V operating
−24 V to +80 V survival
EMI
FILTER
AD8209
EMI
IN+
IN–
+
+
FILTER
OUT
G = 7
–
G = 2
–
EMI
FILTER
Buffered output voltage
Gain = 14 V/V
Low-pass filter (single-pole or two-pole)
Wide operating temperature range
8-lead MSOP: −40°C to +125°C
Excellent ac and dc performance
1 mV voltage offset
GND
Figure 1.
−5 ppm/°C typical gain drift
80 dB CMRR minimum dc to 10 kHz
APPLICATIONS
High-side current sensing
Motor controls
Solenoid controls
Power management
Low-side current sensing
Diagnostic protection
GENERAL DESCRIPTION
The AD8209 is a single-supply difference amplifier ideal for
amplifying and low-pass filtering small differential voltages in the
presence of a large common-mode voltage. The input common-
mode voltage range extends from −2 V to +45 V at a single +5 V
supply. The AD8209 is qualified per AEC-Q100 specifications. The
amplifier offers enhanced input overvoltage and ESD protection,
and includes EMI filtering.
performance, minimizing errors in the application. Typical offset
and gain drift in the MSOP package are less than 5 μV/°C and
10 ppm/°C, respectively. The device also delivers a minimum
CMRR of 80 dB from dc to 10 kHz.
The AD8209 features an externally accessible 100 kΩ resistor at
the output of the preamplifier (A1), which can be used for low-
pass filtering and for establishing gains other than 14.
Automotive applications demand robust, precision components for
improved system control. The AD8209 provides excellent ac and dc
Rev. 0
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