Low Power, Wide Supply Range,
Low Cost Difference Amplifiers, G = ½, 2
Wide input range beyond supplies
Rugged input overvoltage protection
Low supply current: 200 μA maximum (per amplifier)
Low power dissipation: 0.5 mW at VS = 2.5 V
Bandwidth: 1 MHz (G = ½)
CMRR: 80 dB minimum, dc to 20 kHz (G = ½, B Grade)
Low offset voltage drift: ±1 μV/°C maximum (B Grade)
Low gain drift: 1 ppm/°C maximum (B Grade)
Enhanced slew rate: 1.4 V/μs
Wide power supply range
Single supply: 2 V to 36 V
Dual supplies: ±2 V to ±18 V
8-lead SOIC, 14-lead SOIC, and 8-lead MSOP packages
Voltage measurement and monitoring
Current measurement and monitoring
Instrumentation amplifier building block
Portable, battery-powered equipment
Test and measurement
The AD8278 and AD8279 are general-purpose difference
amplifiers intended for precision signal conditioning in power
critical applications that require both high performance and low
power. The AD8278 and AD8279 provide exceptional common-
mode rejection ratio (80 dB) and high bandwidth while amplifying
input signals that are 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 amplifier extends to almost
triple the supply voltage (for G = ½), making the amplifer 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 amp.
The AD8278 and AD8279 can be used as difference amplifiers with
G = ½ or G = 2. They can also be connected in a high precision,
single-ended configuration for non inverting and inverting gains of
−½, −2, +3, +2, +1½, +1, or +½. The AD8278 and AD8279
provide an integrated precision solution that has a smaller size,
lower cost, and better performance than a discrete alternative.
The AD8278 and AD8279 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, which is ideal for battery-operated and portable
systems. For unity-gain difference amplifiers with similar
performance, refer to the AD8276 and AD8277 data sheets.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
FUNCTIONAL BLOCK DIAGRAMS
Figure 1. AD8278
Figure 2. AD8279
Table 1. Difference Amplifiers by Category
1U = unidirectional, B = bidirectional.
The AD8278 is available in the space-saving 8-lead MSOP and
SOIC packages, and the AD8279 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
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