AD8276 Datasheet, PDF (1/20 Pages) Analog Devices – Low Power, Wide Supply Range, Low Cost Unity-Gain Difference Amplifiers

Low Power, Wide Supply Range, Low Cost
Unity-Gain Difference Amplifiers
AD8276/AD8277
FEATURES
Wide input range beyond supplies
Rugged input overvoltage protection
Low supply current: 200 μA maximum per channel
Low power dissipation: 0.5 mW at VS = 2.5 V
Bandwidth: 550 kHz
CMRR: 86 dB minimum, dc to 10 kHz
Low offset voltage drift: ±2 μV/°C maximum (B Grade)
Low gain drift: 1 ppm/°C maximum (B Grade)
Enhanced slew rate: 1.1 V/μs
Wide power supply range:
Single supply: 2 V to 36 V
Dual supplies: ±2 V to ±18 V
APPLICATIONS
Voltage measurement and monitoring
Current measurement and monitoring
Differential output instrumentation amplifier
Portable, battery-powered equipment
Test and measurement
GENERAL DESCRIPTION
The AD8276/AD8277 are general-purpose, unity-gain difference
amplifiers intended for precision signal conditioning in power
critical applications that require both high performance and low
power. They provide exceptional common-mode rejection ratio
(86 dB) and high bandwidth while amplifying signals well beyond
the supply rails. The on-chip resistors are laser-trimmed for
excellent gain accuracy and high CMRR. They also have extremely
low gain drift vs. temperature.
The common-mode range of the amplifiers extends to almost
double the supply voltage, making these amplifiers ideal for single-
supply applications that require a high common-mode voltage
range. The internal resistors and ESD circuitry at the inputs also
provide overvoltage protection to the op amps.
The AD8276/AD8277 are unity-gain stable. While they are
optimized for use as difference amplifiers, they can also be
connected in high precision, single-ended configurations with
G = −1, +1, +2. The AD8276/AD8277 provide an integrated
precision solution that has smaller size, lower cost, and better
performance than a discrete alternative.
The AD8276/AD8277 operate on single supplies (2.0 V to 36 V)
or dual supplies (±2 V to ±18 V). The maximum quiescent
supply current is 200 μA per channel, which is ideal for battery-
operated and portable systems.
FUNCTIONAL BLOCK DIAGRAM
+VS
–IN 2
40kΩ
7
AD8276
40kΩ
5 SENSE
6 OUT
40kΩ
+IN ³
40kΩ
1 _REF
–INA 2
4
–VS
Figure 1. AD8276
+VS
40kΩ
11
AD8277
40kΩ
12 SENSEA
40kΩ
+INA ³
40kΩ
–INB 6
13 OUTA
40kΩ
14 _REFA
40kΩ
10 SENSEB
9 OUTB
40kΩ
+INB ⁵
40kΩ
8 _REFB
4
–VS
Figure 2. AD8277
Table 1. Difference Amplifiers by Category
Low
Distortion
AD8270
AD8271
AD8273
AD8274
AMP03
High
Voltage
AD628
AD629
Current
Sensing¹
AD8202 (U)
AD8203 (U)
AD8205 (B)
AD8206 (B)
AD8216 (B)
Low Power
AD8276
AD8277
AD8278
1 _{U = unidirectional, B = bidirectional.}
The AD8276 is available in the space-saving 8-lead MSOP and
SOIC packages, and the AD8277 is offered in a 14-lead SOIC
package. Both are specified for performance over the industrial
temperature range of −40°C to +85°C and are fully RoHS
compliant.
Rev. A
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