Low Cost, Low Power 12-Bit

Differential ADC Driver

AD8137

Rev. B

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FEATURES

Fully differential

Extremely low power with power-down feature

2.6 mA quiescent supply current @ 5 V

450 µA in power-down mode @ 5 V

High speed

110 MHz large signal 3 dB bandwidth @ G = 1

450 V/µs slew rate

12-bit SFDR performance @ 500 kHz

Fast settling time: 100 ns to 0.02%

Low input offset voltage: ±2.6 mV max

Low input offset current: 0.45 µA max

Differential input and output

Differential-to-differential or single-ended-to-differential

operation

Rail-to-rail output

Adjustable output common-mode voltage

Externally adjustable gain

Wide supply voltage range: 2.7 V to 12 V

Available in small SOIC package

APPLICATIONS

12-bit ADC drivers

Portable instrumentation

Battery-powered applications

Single-ended-to-differential converters

Differential active filters

Video amplifiers

Level shifters

FUNCTIONAL BLOCK DIAGRAM

–IN

1

+OUT

4

+IN

8

PD

7

6

–OUT

5

AD8137

Figure 1.

FREQUENCY (MHz)

3

2

1

0

–12

–11

–10

–9

–8

–7

–6

–5

–4

–3

–2

–1

0.1

1

10

100

1000

G = 5

G = 10

G = 1

G = 2

Figure 2. Small Signal Response for Various Gains

GENERAL DESCRIPTON

The AD8137 is a low cost differential driver with a rail-to-rail

output that is ideal for driving 12-bit ADCs in systems that are

sensitive to power and cost. The AD8137 is easy to apply, and its

internal common-mode feedback architecture allows its output

common-mode voltage to be controlled by the voltage applied

to one pin. The internal feedback loop also provides inherently

balanced outputs as well as suppression of even-order harmonic

distortion products. Fully differential and single-ended-to-

differential gain configurations are easily realized by the

AD8137. External feedback networks consisting of four resistors

determine the amplifier’s closed-loop gain. The power-down

feature is beneficial in critical low power applications.

The AD8137 is manufactured on Analog Devices’ proprietary

second generation XFCB process, enabling it to achieve high

levels of performance with very low power consumption.

The AD8137 is available in the small 8-lead SOIC package and

3 mm × 3 mm LFCSP. It is rated to operate over the extended

industrial temperature range of −40°C to +125°C.