G = 0.2, Level Translation,
16-Bit ADC Driver
AD8275
FEATURES
PIN CONFIGURATION
Translates 10 V to +4 V
Drives 16-bit SAR ADCs
Small MSOP package
Input overvoltage: +40 V to −35 V (VS = 5 V)
Fast settling time: 450 ns to 0.001%
Rail-to-rail output
Wide supply operation: +3.3 V to +15 V
High CMRR: 80 dB
REF1
–IN
1
2
3
4
8
7
6
5
REF2
AD8275
+V
S
TOP VIEW
+IN
OUT
(Not to Scale)
–V
SENSE
S
Figure 1.
TYPICAL APPLICATION
+5V
0.1µF
0.1µF
Low gain drift: 1 ppm/°C
Low offset drift: 2.5 μV/°C
7
+4.048V
+2.048V
+0.048V
+V
S
+10V
50kΩ
–IN
10kΩ
2
5
APPLICATIONS
SENSE
33Ω
VDD
AD7685
IN+
IN–
OUT
Level translator
ADC driver
6
2.7nF
REF
GND
50kΩ
+IN
20kΩ
20kΩ
Instrumentation amplifier building block
Automated test equipment
3
8
1
VIN
–10V
REF2
REF1
VREF
4.096V
10µF
AD8275 –V
S
4
Figure 2. Translating 10 V to 4.096 V ADC Full Scale
GENERAL DESCRIPTION
The AD8275 is a G = 0.2 difference amplifier that can be used
to translate ±±0 V signals to a +4 V level. It solves the problem
typically encountered in industrial and instrumentation applic-
ations where ±±0 V signals must be interfaced to a single-supply
4 V or 5 V ADC. The AD8275 interfaces the two signal levels,
simplifying design.
The AD8275 can be used as an analog front end, or it can follow
buffers to level translate high voltages to a voltage range accepted
by the ADC. In addition, the AD8275 can be configured for diff-
erential outputs if used with a differential ADC.
The AD8275 is available in a space-saving, 8-lead MSOP
and is specified for performance over the −40°C to +85°C
temperature range.
The AD8275 has fast settling time of 450 ns and low distortion,
making it suitable for driving medium speed successive approx-
imation (SAR) ADCs. Its wide input voltage range and rail-to-
rail outputs make it an easy to use building block. Single-supply
operation reduces the power consumption of the amplifier and
helps to protect the ADC from overdrive conditions.
Table 1. Difference Amplifiers by Category
Single-Supply
Current Sense
Low Distortion
AD8270
High Voltage
AD628
AD8202
AD8273
AD629
AD8203
Internal, matched, precision laser-trimmed resistors ensure
low gain error, low gain drift of ± ppm/°C (maximum), and
high common-mode rejection of 80 dB. Low offset and low
offset drift, combined with its fast settling time, make the
AD8275 suitable for a variety of data acquisition applications
where accurate and quick capture is required.
AD8274
AD8205
AD8275
AD8206
AMP03
AD8216
Rev. 0
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