June 16, 2008
LMP7732
2.9 nV/sqrt(Hz) Low Noise, Precision, RRIO Amplifier
General Description
Features
The LMP7732 is a dual low noise, low offset voltage, rail-to-
rail input and output, low voltage precision amplifier. The
LMP7732 is part of the LMP® precision amplifier family and is
ideal for precision and low noise applications with low voltage
requirements.
(Typical values, TA = 25°C, VS = 5V)
Input voltage noise
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f = 3 Hz
3.3 nV/√Hz
2.9 nV/√Hz
±40 µV
±1.3 µV/°C
130 dB
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f = 1 kHz
Offset voltage (max)
Offset voltage drift (max)
CMRR
Open loop gain
GBW
Slew rate
THD @ f = 10 kHz, AV = 1, RL = 2 kΩ
Supply current
Supply voltage range
Operating temperature range
Input bias current
RRIO
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This operational amplifier offers low voltage noise of 2.9 nV/
with a 1/f corner of only 3 Hz and low DC offset with a
maximum value of ±40 µV, targeting high accuracy, low fre-
quency applications. The LMP7732 has bipolar junction input
stages with a bias current of only 1.5 nA. This low input bias
current, complemented by the very low AC and DC levels of
voltage noise, makes the LMP7732 an excellent choice for
photometry applications.
130 dB
22 MHz
2.4 V/µs
0.001%
4.4 mA
1.8V to 5.5V
−40°C to 125°C
±1.5 nA
The LMP7732 provides a wide GBW of 22 MHz while con-
suming only 4 mA of current. This high gain bandwidth along
with the high open loop gain of 130 dB enables accurate sig-
nal conditioning in applications with high closed loop gain
requirements.
The LMP7732 has a supply voltage range of 1.8V to 5.5V,
making it an ideal choice for battery operated portable appli-
cations.
Applications
Thermopile amplifier
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Gas analysis instruments
The LMP7732 is offered in the 8-Pin SOIC and MSOP pack-
ages.
Photometric instrumentation
Medical instrumentation
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The LMP7731 is the single version of this product and is of-
fered in the 5-Pin SOT-23 and 8-Pin SOIC packages.
Typical Application
Thermopile Signal Amplifier
30015001
LMP® is a registered trademark of National Semiconductor Corporation.
© 2008 National Semiconductor Corporation
300150
www.national.com