Dual/Quad Low Power, High Speed
JFET Operational Amplifiers
AD8682/AD8684
Rev. B
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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
OUT A
1
–IN A
2
+IN A
3
V–
4
V+
8
OUT B
7
–IN B
6
+IN B
5
AD8682
TOP VIEW
(Not to Scale)
6278-001
Figure 1. 8-Lead SOIC_N and 8-Lead MSOP
OUT A
1
–IN A
2
+IN A
3
V+
4
OUT D
14
–IN D
13
+IN D
12
V–
11
+IN B
5
+IN C
10
–IN B
6
–IN C
9
OUT B
7
OUT C
8
AD8684
TOP VIEW
(Not to Scale)
06278-002
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.
