Dual/Quad Low Power, High Speed

JFET Operational Amplifiers

AD8682/AD8684

Rev. A

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FEATURES

Low supply current: 250 μA/amp maximum

High slew rate: 9 V/μs

Bandwidth: 3.5 MHz typical

Low offset voltage: 1 mV maximum @ 25°C

Low input bias current: 20 pA maximum @ 25°C

CMRR: 90 dB typical

Fast settling time

Unity gain stable

APPLICATIONS

Portable telecommunications

Low power industrial and instrumentation

Loop filters

Active and precision filters

Integrators

Strain gauge amplifiers

Portable medical instrumentation

Supply current monitoring

PIN CONFIGURATIONS

V+

8

OUT B

7

–IN B

6

+IN B

5

AD8682

TOP VIEW

(Not to Scale)

Figure 1. 8-Lead SOIC_N and 8-Lead MSOP

OUT D

14

–IN D

13

+IN D

12

V–

11

+IN C

10

–IN C

9

OUT C

8

AD8684

TOP VIEW

(Not to Scale)

Figure 2. 14-Lead SOIC_N and 14-Lead TSSOP

GENERAL DESCRIPTION

The AD8682 and AD8684 are dual and quad low power, precision

(1 mV) JFET amplifiers featuring excellent speed at low supply

currents. The slew rate is typically 9 V/μs with a supply current

under 250 μA per amplifier. These unity-gain stable amplifiers

have a typical gain bandwidth of 3.5 MHz. The JFET input stage

ensures bias current is typically a few picoamps and below 125 pA

maximum over the full temperature operating range.

The devices are ideal for portable, low power applications,

especially with high source impedance. The devices are unity gain

stable and can drive higher capacity loads (G = 1, noninverting),

as an example of their excellent dynamic response over a wide

range of conditions, delivering dc precision performance at low

quiescent currents.