
Analog Devices
GENERAL DESCRIPTION
The AD743 is an ultralow noise, precision, FET input, monolithic operational amplifier. It offers a combination of the ultralow voltage noise generally associated with bipolar input op amps and the very low input current of a FET input device. Furthermore, the AD743 does not exhibit an output phase reversal when the negative common-mode voltage limit is exceeded.
The AD743’s guaranteed, maximum input voltage noise of
4.0 nV/√Hz at 10 kHz is unsurpassed for a FET input monolithic op amp, as is the maximum 1.0 µV p-p, 0.1 Hz to 10 Hz noise. The AD743 also has excellent dc performance with 250 pA maximum input bias current and 0.5 mV maximum offset voltage.
The AD743 is specifically designed for use as a preamp in capacitive sensors, such as ceramic hydrophones. The AD743J is rated over the commercial temperature range of 0°C to 70°C.
The AD743 is available in a 16-lead SOIC and 8-lead PDIP.
FEATURES
Ultralow Noise Performance
2.9 nV/√Hz at 10 kHz
0.38 μV p-p, 0.1 Hz to 10 Hz
6.9 fA/√Hz Current Noise at 1 kHz
Excellent DC Performance
0.5 mV Max Offset Voltage
250 pA Max Input Bias Current
1000 V/mV Min Open-Loop Gain
AC Performance
2.8 V/μs Slew Rate
4.5 MHz Unity-Gain Bandwidth
THD = 0.0003% @ 1 kHz
Available in Tape and Reel in Accordance with
EIA-481A Standard
APPLICATIONS
Sonar Preamplifiers
High Dynamic Range Filters (>140 dB)
Photodiode and IR Detector Amplifiers
Accelerometers