LT1793 Low Noise, Picoampere Bias Current, JFET Input Op Amp FEATURES DESCRIPTIO n Input Bias Current, Warmed Up: 10pA Max The LT 1793 achieves a new standard of excellence in n noise performance for a JFET op amp. For the first time low 100% Tested Low Voltage Noise: 8nV/ Hz Max n voltage noise (6nV/ Hz) is simultaneously offered with A Grade 100% Temperature Tested n extremely low current noise (0.8fA/ Hz), providing the Offset Voltage Over Temp: 1mV Max 13 n lowest total noise for high impedance transducer applica- Input Resistance: 10 W n tions. Unlike most JFET op amps, the very low input bias Very Low Input Capacitance: 1.5pF n current (3pA typ) is maintained over the entire common Voltage Gain: 1 Million Min n mode range which results in an extremely high input resis- Gain-Bandwidth Product: 4.2MHz Typ 13 n tance (10 W ). When combined with a very low input ca- Guaranteed Specifications with 5V Supplies pacitance (1.5pF) an extremely high input impedance U results, making the LT1793 the first choice for amplifying APPLICATIO S low level signals from high impedance transducers. The low input capacitance also assures high gain linearity when n Photocurrent Amplifiers buffering AC signals from high impedance transducers. n Hydrophone Amplifiers n High Sensitivity Piezoelectric Accelerometers The LT1793 is unconditionally stable for gains of 1 or more, n Low Voltage and Current Noise Instrumentation even with 1000pF capacitive loads. Other key features are Amplifier Front Ends 250m V V and a voltage gain over 4 million. Each indi- OS n Two and Three Op Amp Instrumentation Amplifiers vidual amplifier is 100% tested for voltage noise, slew rate n Active Filters (3.4V/m s) and gain-bandwidth product (4.2MHz). , LTC and LT are registered trademarks of Linear Technology Corporation. Specifications at 5V supply operation are also provided. For an even lower voltage noise please see the LT1792 data sheet. TYPICAL APPLICATIO Low Noise Light Sensor with DC Servo C1 1kHz Output Voltage Noise 2pF Density vs Source Resistance 10k + V R1 1M 2 7 V N 1k + 6 V LT1793 OUT R SOURCE + C2 0.022m F 3 D2 4 1N914 100 + V V R2 100k C D D1 R3 1N914 10 V N 1k 2N3904 LT1097 SOURCE T = 25C A RESISTANCE V = 15V S HAMAMATSU ONLY R5 R4 1 S1336-5BK 10k 1k 100 1k 10k 100k 1M 10M 100M 1G 1793 TA01 (908) 231-0960 V R2C2 > C1R1 SOURCE RESISTANCE (W ) C = PARASITIC PHOTODIODE CAPACITANCE D 2 2 V = (V ) + 4kTR + 2qI R V V = 100mV/m WATT FOR 200nm WAVE LENGTH N OP AMP S B S OUT 330mV/m WATT FOR 633nm WAVE LENGTH 1793 TA02 1 TOTAL 1kHz VOLTAGE NOISE DENSITY (nV/ Hz) + U ULT1793 (Note 1) ABSOLUTEXAI U RATI GS Specified Temperature Range Supply Voltage ..................................................... 20V Commercial (Note 8) ......................... 40 C to 85 C Differential Input Voltage ...................................... 40V Industrial ........................................... 40 C to 85 C Input Voltage (Equal to Supply Voltage) ............... 20V Storage Temperature Range ................ 65 C to 150 C Output Short-Circuit Duration ........................ Indefinite Lead Temperature (Soldering, 10 sec) ................ 300 C Operating Temperature Range............... 40 C to 85 C / PACKAGE ORDER I FOR ATIO ORDER PART ORDER PART NUMBER NUMBER TOP VIEW TOP VIEW V ADJ 1 NC V ADJ 1 8 NC OS 8 OS LT1793ACS8 LT1793ACN8 + IN A IN A 2 7 V 2 7 V+ LT1793CS8 LT1793CN8 A A +IN A +IN A OUT 3 6 OUT 3 6 LT1793AIS8 LT1793AIN8 V V 4 V ADJ V ADJ 5 4 5 OS OS LT1793IS8 LT1793IN8 N8 PACKAGE S8 PACKAGE S8 PART MARKING 8-LEAD PDIP 8-LEAD PLASTIC SO T = 150 C, q = 80 C/W T = 160 C, q = 190 C/W JMAX JA JMAX JA 1793A 1793AI 1793 1793I Consult factory for Military grade parts. T = 25 C, V = 15V, V = 0V, unless otherwise noted. ELECTRICAL CHARACTERISTICS A S CM LT1793AC/LT1793AI LT1793C/LT1793I SYMBOL PARAMETER CONDITIONS (Note 2) MIN TYP MAX MIN TYP MAX UNITS V Input Offset Voltage 0.25 0.8 0.25 0.9 mV OS V = 5V 0.45 1.4 0.45 1.6 mV S I Input Offset Current Warmed Up (Note 3) 1.5 7 2.5 15 pA OS T = 25 C (Note 6) 0.5 2 0.7 4 pA J I Input Bias Current Warmed Up (Note 3) 3 10 4.0 20 pA B T = 25 C (Note 6) 1 3 1.5 5 pA J e Input Noise Voltage 0.1Hz to 10Hz 2.4 2.4 m V n P-P Input Noise Voltage Density f = 10Hz 11.5 11.5 nV/ Hz O f = 1000Hz 6 8 6 8 nV/ Hz O i Input Noise Current Density f = 10Hz, f = 1kHz (Note 4) 0.8 1 fA/ Hz n O O R Input Resistance IN 14 14 Differential Mode 10 10 W 13 13 Common Mode V = 10V to 13V 10 10 W CM C Input Capacitance 1.5 1.5 pF IN V = 5V 2.0 2.0 pF S V Input Voltage Range (Note 5) 13.0 13.5 13.0 13.5 V CM 10.5 11.0 10.5 11.0 V CMRR Common Mode Rejection Ratio V = 10V to 13V 83 102 81 96 dB CM PSRR Power Supply Rejection Ratio V = 4.5V to 20V 85 98 83 95 dB S 2 U WU U W W W