Low Power, 3.6 MHz, Low Noise, Rail-to-
Rail Output, Operational Amplifiers
ADA4691-2/ADA4691-4/ADA4692-2/ADA4692-4
The ADA4691/ADA4692 family is fully specified over the extended
industrial temperature range (−40°C to +125°C). The ADA4691-2
is available in a 10-lead LFCSP and a 9-ball WLCSP. The ADA4692-2
is available in an 8-lead SOIC and 8-lead LFCSP. The ADA4691-4 is
available in a 16-lead LFCSP. The ADA4692-4 is available in a 14-lead
TSSOP. For pin configurations, see the Pin Configurations section.
FEATURES
Low power: 180 μA typical
Very low input bias currents: 0.5 pA typical
Low noise: 16 nV/√Hz typical
3.6 MHz bandwidth
Offset voltage: 500 μV typical
Low offset voltage drift: 4 μV/°C maximum
Low distortion: 0.003% THD + N
2.7 V to 5 V single supply or 1.35 V to 2.5 V dual supply
Available in very small 2 mm × 2 mm LFCSP packages
1
ADA4692-2
V
= ±2.5V
SY
A
= –1
= 25°C
V
A
APPLICATIONS
T
Photodiode amplifiers
Sensor amplifiers
Portable medical and instrumentation
Portable audio: MP3s, PDAs, and smartphones
Communications
0.1
0.01
R
= 600Ω
L
R
= 2kΩ
L
Low-side current sense
ADC drivers
Active filters
Sample-and-hold
0.001
GENERAL DESCRIPTION
10
100
1k
FREQUENCY (Hz)
10k 20k
The ADA4691-2/ADA4692-2 are dual and the ADA4691-4/
ADA4692-4 are the quad rail-to-rail output, single-supply
amplifiers featuring low power, wide bandwidth, and low noise.
The ADA4691-2 has two independent shutdown pins, allowing
further reduction in supply current. The ADA4691-4 is a quad
with dual shutdown pins each controlling a pair of amplifiers
and is available in the 16-lead LFCSP. The ADA4692-4 is a quad
version without shutdown.
Figure 1. THD + Noise vs. Frequency
–80
–90
ADA4692-2
V
V
= ±2.5V
= 2.8V p-p
= +1
SY
IN
A
V
A
T
= 25°C
–100
–110
–120
–130
–140
These amplifiers are ideal for a wide variety of applications.
Audio, filters, photodiode amplifiers, and charge amplifiers, all
benefit from this combination of performance and features.
Additional applications for these amplifiers include portable
consumer audio players with low noise and low distortion that
provide high gain and slew rate response over the audio band at
low power. Industrial applications with high impedance sensors,
such as pyroelectric and IR sensors, benefit from the high
impedance and low 0.5 pA input bias, low offset drift, and
enough bandwidth and response for low gain applications.
100
1k
10k
FREQUENCY (Hz)
100k
Figure 2. Channel Separation vs. Frequency
Table 1.
Micropower
AD8613
AD8617
Low Power
Low Power with Shutdown
Standard Op Amp With Shutdown
High Bandwidth
AD8691
AD8692
Single
Dual
Quad
AD8591
AD8592
AD8594
ADA4692-2
ADA4692-4
ADA4691-2
ADA4691-4
AD8619
AD8694
Rev. C
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