LTC1250 Very Low Noise Zero-Drift Bridge Amplifier DESCRIPTIO FEATURES Very Low Noise: 0.75V Typ, 0.1Hz to 10Hz The LTC 1250 is a high performance, very low noise zero- P-P DC to 1Hz Noise Lower Than OP-07 drift operational amplifier. The LTC1250s combination of Full Output Swing into 1k Load low front-end noise and DC precision makes it ideal for use Offset Voltage: 10V Max with low impedance bridge transducers. The LTC1250 Offset Voltage Drift: 50nV/C Max features typical input noise of 0.75V from 0.1Hz to P-P Common Mode Rejection Ratio: 110dB Min 10Hz, and 0.2V from 0.1Hz to 1Hz. The LTC1250 has P-P Power Supply Rejection Ratio: 115dB Min DC to 1Hz noise of 0.35V , surpassing that of low noise P-P No External Components Required bipolar parts including the OP-07, OP-77, and LT1012. Pin Compatible with Standard 8-Pin Op Amps The LTC1250 uses the industry-standard single op amp Available in Standard 8-Pin Plastic DIP pinout, and requires no external components or nulling and 8-Pin SO Packages signals, allowing it to be a plug-in replacement for bipolar op amps. U The LTC1250 incorporates an improved output stage APPLICATIO S capable of driving 4.3V into a 1k load with a single 5V Electronic Scales supply it will swing 4.9V into 5k with 5V supplies. The Strain Gauge Amplifiers input common mode range includes ground with single Thermocouple Amplifiers power supply voltages above 12V. Supply current is 3mA High Resolution Data Acquisition with a 5V supply, and overload recovery times from Low Noise Transducers positive and negative saturation are 0.5ms and 1.5ms, Instrumentation Amplifiers respectively. The internal nulling clock is set at 5kHz for optimum low frequency noise and offset drift no external , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents connections are necessary. including 4933642. The LTC1250 is available in a standard 8-pin plastic DIP and 8-pin SO packages. TYPICAL APPLICATIO Differential Bridge Amplifier Input Referred Noise 0.1Hz to 10Hz 2 5V 5V V = 5V S A = 10k V 50 1000pF GAIN 0.1F 1 TRIM 18.2k 0 350 2 7 STRAIN GAUGE 6 LTC1250 A = 100 V 1 3 + 4 1000pF 18.2k 2 0 2 4 6 8 10 5V 5V 1250 TA01 TIME (s) LT1250 TA02 1250fb 1 V U ULTC1250 ABSOLUTE AXI U RATI GS (Note 1) + Operating Temperature Range Total Supply Voltage (V to V ) ............................. 18V + LTC1250M (OBSOLETE) ............ 55C to 125C Input Voltage ........................ (V + 0.3V) to (V 0.3V) LTC1250C .......................................... 0C TO 70C Output Short Circuit Duration ......................... Indefinite Storage Temperature Range ................ 65C to 150C Lead Temperature (Soldering, 10 sec.)................ 300C / PACKAGE ORDER I FOR ATIO TOP VIEW ORDER PART ORDER PART NUMBER NUMBER NC 1 8 NC TOP VIEW + IN 2 7 V LTC1250CS8 LTC1250CN8 +IN 3 OUT NC 1 8 NC 6 + V 4 5 NC IN 2 7 V +IN 3 6 OUT N8 PACKAGE 8-LEAD PLASTIC DIP NC V 4 5 S8 PART MARKING T = 110C, = 130CW JMAX JA S8 PACKAGE J8 PACKAGE 8-LEAD PLASTIC SO LTC1250MJ8 1250 8-LEAD CERAMIC DIP T = 110C, = 200CW JMAX JA T = 150C, = 100CW (J8) JMAX JA LTC1250CJ8 OBSOLETE PACKAGE Consider the N8 or S8 for Alternative Source Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, V = 5V, otherwise specifications are at T = 25C. IN A LTC1250M LTC1250C SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS V Input Offset Voltage T = 25C (Note 2) 5 10 5 10 V OS A V Average Input Offset Drift (Note 2) 0.01 0.05 0.01 0.05 V/C OS Long Term Offset Drift 50 50 nV/Mo e Input Noise Voltage (Note 3) T = 25C, 0.1Hz to 10Hz 0.75 1.0 0.75 1.0 V n A P-P T = 25C, 0.1Hz to 1Hz 0.2 0.2 V A P-P i Input Noise Current f = 10Hz 4.0 4.0 fA/Hz n I Input Bias Current T = 25C (Note 4) 50 150 50 200 pA B A 950 450 pA I Input Offset Current T = 25C (Note 4) 100 300 100 400 pA OS A 500 500 pA CMRR Common Mode Rejection Ratio V = 4V to 3V 110 130 110 130 dB CM PSRR Power Supply Rejection Ratio V = 2.375V to 8V 115 130 115 130 dB S A Large-Signal Voltage Gain R = 10k, V = 4V 125 170 125 170 dB VOL L OUT Maximum Output Voltage Swing R = 1k 4.0 4.3/4.7 4.0 4.3/4.7 V L R = 100k 4.92 4.95 V L SR Slew Rate R = 10k, C = 50pF 10 10 V/s L L GBW Gain-Bandwidth Product 1.5 1.5 MHz I Supply Current No Load, T = 25C 3.0 4.0 3.0 4.0 mA S A 7.0 5.0 mA 1250fb 2 U WU U WWW