LT1672_15 Datasheet, PDF (1/12 Pages) Linear Technology – Quad Over-The-Top Precision Rail-to-Rail Input and Output Op Amps

LT1672/LT1673/LT1674
2µA Max, A_V ≥ 5 Single, Dual
and Quad Over-The-Top Precision
Rail-to-Rail Input and Output Op Amps
FEATURES
s _{Gain of 5 Stable}
s _{Low Supply Current: 2µA Max per Amplifier}
s _{Rail-to-Rail Input and Output}
s _{Low Offset Voltage: 375µV Max}
s _Over-The-Top^TM _{Inputs Operate Above V}⁺
s _{Gain Bandwidth Product: 12kHz}
s _{Wide Supply Range: 2.2V to 36V}
s _{Single Supply Input Range: – 0.3V to 36V}
s _{Low Input Bias Current: 250pA}
s _{Low Input Offset Current: 20pA}
s _{High AVOL: 100V/mV Minimum Driving 100kΩ Load}
s _{Output Sources and Sinks 500µA Load Current}
s _{Reverse Battery Protected to 18V}
U
APPLICATIO S
s _{Battery- or Solar-Powered Systems}
s _{Portable Instrumentation}
s _{Remote Sensor Amplifier}
s _{Micropower Filter}
s _{Photodiode Amplifier}
s _{High Impedance Circuits}
, LTC and LT are registered trademarks of Linear Technology Corporation.
Over-The-Top is a trademark of Linear Technology Corporation.
DESCRIPTIO
The LT^®1672/LT1673/LT1674 are ultralow power
(I_S ≤ 2µA) decompensated (A_V ≥ 5) op amps with preci-
sion specifications. The extremely low supply current is
combined with excellent amplifier specifications: input
offset voltage is 375µV maximum with a typical drift of
only 0.4µV/°C, input offset current is 100pA maximum. A
minimum open-loop gain (A_VOL) of 100V/mV ensures that
gain errors are small. The devices’ characteristics change
little over the supply range of 2.2V to ±15V. Supply
rejection is 90dB and the common mode rejection ratio is
90dB. Operation is specified for 3V, 5V and ±15V supplies.
Reverse battery protection (–18V min) and inputs that
operate above the positive supply make the LT1672/
LT1673/LT1674 easy to use in harsh environments.
The low bias currents and offset current of the amplifier
permit the use of megohm level source resistors without
introducing significant errors. Voltage noise at 4µV_P-P is
remarkably low considering the low supply current. For
unity gain stable versions of these amplifiers, see the
LT1494/LT1495/LT1496.
The LT1672 is available in the 8-pin MSOP, PDIP and SO
packages. The LT1673 is available in plastic 8-pin PDIP
and SO-8 packages with the standard dual op amp pinout.
The LT1674 is available in 14-pin PDIP and SO packages.
TYPICAL APPLICATION
Single Supply, 60µW Precision Instrumentation Amplifier
5V
100k*
V_IN1
+
1/2 LT1673
–
110k
1M
1000pF
1M
110k
–
1/2 LT1673
100k*
V_IN2
+
1M
5V
100k
–
LT1672
100k
+
V_OUT
1M
0.0047µF
1M
5V
LT1389-2.5
1672/3/4 TA01
A_V = 100
BANDWIDTH = 1kHz
CMRR = 65dB AT 120Hz
*500V TRANSIENT PROTECTION
TOTAL SUPPLY CURRENT = 12µA
TC V_OS Distribution
80
120 AMPLIFIERS
70 ^VS ^{= ±2.5V}
– 40°C to 85°C
60
50
40
30
20
10
0
–1.5
– 0.9 – 0.3 0.3
TC V_OS (µV/°C)
0.9 1.5
1672/3/4 TA02
1