LTC1250 Datasheet, PDF (1/8 Pages) Linear Technology – Very Low Noise Zero-Drift Bridge Amplifier

LTC1250
Very Low Noise
Zero-Drift Bridge Amplifier
FEATURES
s _{Very Low Noise: 0.75µVP-P Typ, 0.1Hz to 10Hz}
s _{DC to 1Hz Noise Lower Than OP-07}
s _{Full Output Swing into 1k Load}
s _{Offset Voltage: 10µV Max}
s _{Offset Voltage Drift: 50nV/°C Max}
s _{Common-Mode Rejection Ratio: 110dB Min}
s _{Power Supply Rejection Ratio: 115dB Min}
s _{No External Components Required}
s _{Pin-Compatible with Standard 8-Pin Op Amps}
APPLICATI S
s _{Electronic Scales}
s _{Strain Gauge Amplifiers}
s _{Thermocouple Amplifiers}
s _{High Resolution Data Acquisition}
s _{Low Noise Transducers}
s _{Instrumentation Amplifiers}
and LTC are registered trademarks and LT is a trademark of Linear Technology Corporation.
DESCRIPTIO
The LTC^®1250 is a high performance, very low noise zero-
drift operational amplifier. The LTC1250’s combination of
low front-end noise and DC precision makes it ideal for use
with low impedance bridge transducers. The LTC1250
features typical input noise of 0.75µV_P-P from 0.1Hz to
10Hz, and 0.2µV_P-P from 0.1Hz to 1Hz. The LTC1250 has
DC to 1Hz noise of 0.35µV_P-P, surpassing that of low noise
bipolar parts including the OP-07, OP-77, and LT1012.
The LTC1250 uses the industry-standard single op amp
pinout, and requires no external components or nulling
signals, allowing it to be a plug-in replacement for bipolar
op amps.
The LTC1250 incorporates an improved output stage
capable of driving 4.3V into a 1k load with a single 5V
supply; it will swing ±4.9V into 5k with ±5V supplies. The
input common mode range includes ground with single
power supply voltages above 12V. Supply current is 3mA
with a ±5V supply, and overload recovery times from
positive and negative saturation are 0.5ms and 1.5ms,
respectively. The internal nulling clock is set at 5kHz for
optimum low frequency noise and offset drift; no external
connections are necessary.
The LTC1250 is available in standard 8-pin ceramic and
plastic DIPs, as well as an 8-pin SOIC package.
TYPICAL APPLICATI
Differential Bridge Amplifier
5V
5V
50Ω
GAIN
TRIM
0.1µF
1000pF
18.2k
350Ω
STRAIN
GAUGE
2_– 7
LTC1250
6
3₊
4
1000pF _18.2k
–5V
–5V
A_V = 100
1250 TA01
Input Referred Noise 0.1Hz to 10Hz
2
V_S = ±5V
A_V = 10k
1
0
–1
–2
0
2
4
6
8
10
TIME (s)
LT1250 TA02
1