Ultralow Noise BiFET Op Amp AD743 FEATURES CONNECTION DIAGRAMS Ultralow Noise Performance 8-Lead PDIP (N) 16-Lead SOIC (R) 2.9 nV/Hz at 10 kHz 0.38 V p-p, 0.1 Hz to 10 Hz 1 NULL 1 88 NC 168 NC NC 6.9 fA/Hz Current Noise at 1 kHz AD743 OFFSET AD743 IN +V 2 15 2 NC 7 S NULL Excellent DC Performance IN 3 14 0.5 mV Max Offset Voltage +IN 3 NC 6 OUT 250 pA Max Input Bias Current +V V NC 4 4 13 S S 5 NULL TOP VIEW 1000 V/mV Min Open-Loop Gain 12 OUTPUT +IN 5 NC = NO CONNECT AC Performance OFFSET V 6 11 S NULL 2.8 V/ s Slew Rate 10 NC 7 4.5 MHz Unity-Gain Bandwidth NC THD = 0.0003% 1 kHz TOP VIEW NC 8 9 NC Available in Tape and Reel in Accordance with NC = NO CONNECT EIA-481A Standard APPLICATIONS Sonar Preamplifiers High Dynamic Range Filters (>140 dB) 2. The combination of low voltage and low current noise make Photodiode and IR Detector Amplifiers the AD743 ideal for charge sensitive applications such as Accelerometers accelerometers and hydrophones. 3. The low input offset voltage and low noise level of the AD743 GENERAL DESCRIPTION provide >140 dB dynamic range. The AD743 is an ultralow noise, precision, FET input, monolithic 4. The typical 10 kHz noise level of 2.9 nV/Hz permits a three operational amplifier. It offers a combination of the ultralow volt- op amp instrumentation amplifier, using three AD743s, to be age noise generally associated with bipolar input op amps and built which exhibits less than 4.2 nV/Hz noise at 10 kHz the very low input current of a FET input device. Furthermore, and which has low input bias currents. the AD743 does not exhibit an output phase reversal when the negative common-mode voltage limit is exceeded. 1000 R OP27 AND SOURCE The AD743s guaranteed, maximum input voltage noise of RESISTOR 4.0 nV/Hz at 10 kHz is unsurpassed for a FET input mono- ( ) E O lithic op amp, as is the maximum 1.0 V p-p, 0.1 Hz to 10 Hz noise. The AD743 also has excellent dc performance with 250 pA R SOURCE 100 maximum input bias current and 0.5 mV maximum offset voltage. AD743 AND RESISTOR The AD743 is specifically designed for use as a preamp in capaci- AD743 AND OR RESISTOR tive sensors, such as ceramic hydrophones. The AD743J is rated OP27 AND RESISTOR ( ) over the commercial temperature range of 0C to 70C. 10 The AD743 is available in a 16-lead SOIC and 8-lead PDIP. PRODUCT HIGHLIGHTS RESISTOR NOISE ONLY ( ) 1. The low offset voltage and low input offset voltage drift of the AD743 coupled with its ultralow noise performance mean 1 100 1k 10k 100k 1M 10M that the AD743 can be used for upgrading many applications SOURCE RESISTANCE ( ) now using bipolar amplifiers. Figure 1. Input Voltage Noise vs. Source Resistance REV. E Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. may result from its use. No license is granted by implication or otherwise Tel: 781/329-4700 www.analog.com under any patent or patent rights of Analog Devices. Trademarks and Fax: 781/326-8703 2003 Analog Devices, Inc. All rights reserved. registered trademarks are the property of their respective companies. INPUT VOLTAGE NOISE (nV/ Hz)AD743SPECIFICATIONS ( 25 C and 15 V dc, unless otherwise noted.) Parameter Conditions Min Typ Max Unit 1 INPUT OFFSET VOLTAGE Initial Offset 0.25 1.0 mV to T 1.5 mV Initial Offset T MIN MAX vs. Temperature T to T 2 V/C MIN MAX 2 90 96 dB vs. Supply (PSRR) 12 V to 18 V vs. Supply (PSRR) T to T 88 dB MIN MAX 3 INPUT BIAS CURRENT Either Input V = 0 V 150 400 pA CM Either Input T V = 0 V 8.8 nA MAX CM Either Input V = 10 V 250 600 pA CM Either Input, V = 5 V V = 0 V 30 200 pA S CM INPUT OFFSET CURRENT V = 0 V 40 150 pA CM Offset Current T V = 0 V 2.2 nA MAX CM FREQUENCY RESPONSE Gain BW, Small Signal G = 1 4.5 MHz = 20 V p-p 25 kHz Full Power Response V O Slew Rate, Unity Gain G = 1 2.8 V/s Settling Time to 0.01% 6 s 4 Total Harmonic Distortion f = 1 kHz (TPC 16) G = 1 0.0003 % INPUT IMPEDANCE 10 Differential 1 10 20 pF 11 Common Mode 3 10 18 pF INPUT VOLTAGE RANGE 5 Differential 20 V Common-Mode Voltage +13.3, 10.7 V 6 Over Maximum Operating Range 10 +12 V Common-Mode Rejection Ratio V = 10 V 80 95 dB CM T to T 78 dB MIN MAX INPUT VOLTAGE NOISE 0.1 Hz to 10 Hz 0.38 V p-p f = 10 Hz 5.5 nV/Hz f = 100 Hz 3.6 nV/Hz f = 1 kHz 3.2 5.0 nV/Hz f = 10 kHz 2.9 4.0 nV/Hz INPUT CURRENT NOISE f = 1 kHz 6.9 fA/Hz OPEN-LOOP GAIN V = 10 V, O R 2 k 1000 4000 V/mV LOAD T to T 800 V/mV MIN MAX R = 600 1200 V/mV LOAD OUTPUT CHARACTERISTICS Voltage R 600 +13, 12 V LOAD 600 +13.6, 12.6 V R LOAD T to T +12, 10 V MIN MAX 2 k 12 +13.8, 13.1 V R LOAD Current Short Circuit 20 40 mA POWER SUPPLY Rated Performance 15 V Operating Range 4.8 18 V Quiescent Current 8.1 10.0 mA TRANSISTOR COUNT No. of Transistors 50 NOTES 1 Input offset voltage specifications are guaranteed after five minutes of operation at T = 25C. A 2 Test conditions: +V = 15 V, V = 12 V to 18 V and +V = 12 V to 18 V, V = 15 V. S S S S 3 Bias current specifications are guaranteed maximum at either input after 5 minutes of operation at T = 25C. For higher temperature, the current doubles every 10C. A 4 Gain = 1, R = 2 k , C = 10 pF. L L 5 Defined as voltage between inputs, such that neither exceeds 10 V from common. 6 The AD743 does not exhibit an output phase reversal when the negative common-mode limit is exceeded. All min and max specifications are guaranteed. Specifications subject to change without notice. 2 REV. E