LT1792 Low Noise, Precision, JFET Input Op Amp UFEATURESDESCRIPTIO ■ 100% Tested Low Voltage Noise: 6nV/ √ Hz Max The LT®1792 achieves a new standard of excellence in ■ A Grade 100% Temperature Tested noise performance for a JFET op amp. The 4.2nV/√Hz ■ Voltage Gain: 1.2 Million Min voltage noise combined with low current noise and ■ Offset Voltage Over Temp: 800µV Max picoampere bias currents make the LT1792 an ideal choice ■ Gain-Bandwidth Product: 5.6MHz Typ for amplifying low level signals from high impedance ■ Guaranteed Specifications with ±5V Supplies capacitive transducers. The LT1792 is unconditionally stable for gains of 1 or more, U even with load capacitances up to 1000pF. Other key APPLICATIO S features are 600µV VOS and a voltage gain of over 4 million. ■ Photocurrent Amplifiers Each individual amplifier is 100% tested for voltage noise, ■ Hydrophone Amplifiers slew rate and gain bandwidth. ■ High Sensitivity Piezoelectric Accelerometers The design of the LT1792 has been optimized to achieve ■ Low Voltage and Current Noise Instrumentation true precision performance with an industry standard Amplifier Front Ends pinout in the SO-8 package. Specifications are also pro- ■ Two and Three Op Amp Instrumentation Amplifiers vided for ■ ±5V supplies. Active Filters , LTC and LT are registered trademarks of Linear Technology Corporation. UTYPICAL APPLICATIOLow Noise Hydrophone Amplifier with DC Servo1kHz Input Noise Voltage Distribution 5V TO 15V R3 VS = ±15V 270 OP AMPS TESTED R1* 3.9k 40 TA = 25°C 100M 2 – 7 6 LT1792 OUTPUT 30 3 + C1* C2 R2 4 0.47µF 200Ω –5V TO –15V 20 R4 R8 – 2 1M CT R6 100M PERCENT OF UNITS (%) 100k HYDRO- 10 6 R5 LT1097 PHONE + 3 1M R7 1M 03.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6 INPUT VOLTAGE NOISE (nV/√Hz) DC OUTPUT ≤ 2.5mV FOR TA < 70°C OUTPUT VOLTAGE NOISE = 128nV/√Hz AT 1kHz (GAIN = 20) 1792 TA02 1792 TA01 C1 ≈ CT ≈ 100pF TO 5000pF; R4C2 > R8CT; *OPTIONAL 1
