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LMP7721
SNOSAW6E –JANUARY 2008–REVISED DECEMBER 2014
LMP7721 3-Femtoampere Input Bias Current Precision Amplifier
1 Features
3 Description
The LMP7721 is the industry’s lowest specified input
1
•
Unless Otherwise Noted, Typical Values at TA =
25°C, VS = 5 V.
bias current precision amplifier. The ultra-low input
bias current is 3 fA, with a specified limit of ±20 fA at
25°C and ±900 fA at 85°C. This is achieved with the
latest patent-pending technology of input bias current
cancellation amplifier circuitry. This technology also
maintains the ultra-low input bias current over the
entire input common-mode voltage range of the
amplifier.
•
Input Bias Current (VCM = 1 V)
–
–
Maximum at 25°C ±20 fA
Maximum at 85°C ±900 fA
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•
•
•
•
•
•
•
•
•
•
•
Offset Voltage ±26 µV
Offset Voltage Drift −1.5 μV/°C
DC Open-Loop Gain 120 dB
DC CMRR 100 dB
Other outstanding features, such as low voltage noise
(6.5 nV/√Hz), low DC-offset voltage (±150 µV
maximum at 25°C) and low-offset voltage
temperature coefficient (−1.5 µV/°C), improve system
Input Voltage Noise (at f = 1 kHz) 6.5 nV/√Hz
THD 0.0007%
sensitivity
and
accuracy
in
high-precision
Supply Current 1.3 mA
applications. With a supply voltage range of 1.8 V to
5.5 V, the LMP7721 is the ideal choice for battery-
operated, portable applications. The LMP7721 is part
of the LMP™ precision amplifier family.
GBW 17 MHz
Slew Rate (Falling Edge) 12.76 V/μs
Supply Voltage 1.8 V to 5.5 V
Operating Temperature Range −40°C to 125°C
8-Pin SOIC
As part of Texas Instruments' PowerWise™ products,
the LMP7721 provides the remarkably wide-gain
bandwidth product (GBW) of 17 MHz while
consuming only 1.3 mA of current. This wide GBW
along with the high open-loop gain of 120 dB enables
2 Applications
accurate
signal
conditioning.
With
these
•
•
•
•
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•
Photodiode Amplifier
specifications, the LMP7721 has the performance to
excel in a wide variety of applications such as
electrochemical cell amplifiers and sensor interface
circuits.
High Impedance Sensor Amplifier
Ion Chamber Amplifier
Electrometer Amplifier
pH Electrode Amplifier
Transimpedance Amplifier
The LMP7721 is offered in an 8-pin SOIC package
with a special pinout that isolates the amplifier’s input
from the power supply and output pins. With proper
board layout techniques, the unique pinout of the
LMP7721 will prevent PCB leakage current from
reaching the input pins. Thus system error will be
further reduced.
Ultra-Low Input Bias Current
5
0
Device Information(1)
-5
PART NUMBER
PACKAGE
BODY SIZE (NOM)
LMP7721
SOIC (8)
4.90 mm × 3.90 mm
-10
(1) For all available packages, see the orderable addendum at
the end of the datasheet.
+
V
V
5V
=
-15
-20
-
= 0V
T
= 25°C
A
0
0.5
1
1.5
2
2.5
3
3.5
V
CM
(V)
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.