LTC1047_09

LTC1047 Dual Micropower Zero-Drift Operational Amplifier with Internal Capacitors DESCRIPTIO The LTC®1047 is a micropower, high performance dual zero-drift operational amplifier. The sample-and-hold capacitors usually required by other chopper amplifiers are integrated on-chip, minimizing the need for external components. The LTC1047 has a typical offset voltage of 3µV, drift of 10nV/°C, input noise voltage typically 3.5µVP-P, and typical voltage gain of 150dB. The common mode rejection is 110dB minimum, with minimum power supply rejection of 105dB. The LTC1047 also offers a 0.2V/µs slew rate and a gain bandwidth product of 200kHz. Overload recovery time from saturation is 70ms, four times faster than chopper amplifiers with external capacitors. The LTC1047 is available in a standard plastic 8-pin PDIP as well as a 16-pin SW package. The LTC1047 is a plug-in replacement for most dual op amps with improved DC performance and substantial power savings. , LTC and LT are registered trademarks of Linear Technology Corporation. FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ No External Components Required Maximum Offset Voltage: 10µV Maximum Offset Voltage Drift: 50nV/°C Supply Current: 80µA Minimum CMRR: 110dB Minimum PSRR: 105dB Single Supply Operation: 4.75V to 16V Common Mode Range Includes GND Output Swings to GND Typical Overload Recovery Time: 70ms Pin Compatible with Industry Standard Dual Op Amps APPLICATIO S ■ ■ ■ ■ ■ Thermocouple Amplifiers Electronic Scales Battery Powered Instrumentation Strain Gauge Amplifiers Remote Located Sensors TYPICAL APPLICATIO 5V 4 1/2 LTC1043 –IN 18 3 CS 1µF 2 +IN 6 16 0.1µF 17 5 CH 1µF 15 100Ω Micropower Single Supply Instrumentation Amplifier 140 120 100k 5V 6 CS = C H = 1 µ F 100 CMRR (dB) 80 60 – 1/2 LTC1047 7 VOUT 5 + 40 20 100 4 GAIN = 1000 CMRR > = 120dB AT 60Hz VOS = < 10µV IS = 62µA (INCLUDING THE LTC1043) LTC1047 • TA01 1k 10k 100k FREQUENCY OF COMMON MODE SIGNAL LT1047 • TA02 U U U CMRR vs Frequency 1047fa 1 LTC1047 ABSOLUTE AXI U RATI GS Total Supply Voltage (V + to V –) ............................... 16V Input Voltage (Note 2) .......... (V + + 0.3V) to (V – – 0.3V) Output Short-Circuit Duration .......................... Indefinite PACKAGE/ORDER I FOR ATIO TOP VIEW OUT A 1 –IN A 2 +IN A 3 V– 4 8 7 6 5 V+ OUT B –IN B +IN B ORDER PART NUMBER LTC1047CN8 N8 PACKAGE 8-LEAD PDIP TJMAX = 110°C, θJA = 130°C/W Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS PARAMETER Input Offset Voltage Average Input Offset Voltage Drift Long Term Offset Drift Input Bias Current CONDlTlONS TA = 25°C (Note 3) (Note 3) The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ± 5V, unless otherwise noted. MIN ● Input Offset Current ● Input Noise Voltage Input Noise Current Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain Maximum Output Voltage Swing 0.1Hz to 10Hz 0.1Hz to 1Hz f = 10Hz (Note 4) VCM = V – to 2.7V, T A = 25°C VS = ± 2.375V to ± 8V RL = 100k, VOUT = ± 4V RL = 10k RL = 100k 2 U U W WW U W (Note 1) Storage Temperature Range ................. – 65°C to 150°C Operating Temperature Range ..................... 0°C to 70°C Lead Temperature (Soldering, 10 sec).................. 300°C TOP VIEW NC 1 NC 2 OUT A 3 –IN A 4 +IN A 5 V– 6 16 NC 15 NC 14 V + 13 OUT B 12 –IN B 11 +IN B 10 NC 9 NC ORDER PART NUMBER LTC1047CSW NC 7 NC 8 SW PACKAGE 16-LEAD PLASTIC SO WIDE TJMAX = 110°C, θJA = 200°C/W TYP ±3 ± 0.01 100 ±5 MAX ± 10 ± 0.05 ± 30 ± 300 ± 60 ±150 UNITS µV µV/°C nV√mo pA pA pA pA µVP-P µVP-P fA√Hz dB dB dB dB V V ● ±10 3.5 0.8 1.5 ● ● ● ● 110 105 105 120 4.8/–4.9 130 122 150 4.3/–4.8 ± 4.95 1047fa LTC1047 ELECTRICAL CHARACTERISTICS PARAMETER Slew Rate Gain Bandwidth Product Supply Current/Amplifier Internal Sampling Frequency CONDlTlONS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ± 5V, unless otherwise noted. MIN TYP 0.2 200 No Load, 25°C ≤ TA ≤ 70°C No Load, 0°C ≤ TA ≤ 25°C 60 80 680 150 275 MAX UNITS V/µs kHz µA µA Hz RL = 100k, CL = 50pF Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Connecting any terminal to voltages greater than V+ or less than V– may cause destructive latch-up. It is recommended that no sources operating from external supplies be applied prior to power-up of the LTC1047. Note 3: These parameters are guaranteed by design. Thermocouple effects preclude measurements of these voltage levels in high speed automatic test systems. VOS is measured to a limit determined by test equipment capability. Note 4: Current Noise is calculated from the formula: In = √2q • IB) where q = 1.6 • 10–19 Coulomb. TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage Per Amplifier 120 100 SUPPLY CURRENT, IS (µA) 80 60 40 20 0 TA = 25°C 90 SUPPLY CURRENT, IS (µA) 4 14 16 8 10 12 6 TOTAL SUPPLY VOLTAGE, V + TO V – (V) LTC1047 • TPC02 Common Mode Input Range vs Supply Voltage VCM = V – 6 COMMON MODE RANGE (V) SHORT CIRCUIT OUTPUT CURRENT, IOUT (mA) 8 4 2 0 –2 –4 –6 –8 0 1 4 5 2 3 6 SUPPLY VOLTAGE (±V) 7 8 UW Supply Current vs Temperature Per Amplifier VS = ±5V 80 70 60 50 40 50 25 –50 –25 0 75 100 AMBIENT TEMPERATURE, TA (°C) 125 LTC1047 • TPC03 Output Short-Circuit Current vs Supply Voltage 3 2 1 0 –4 –8 –12 VOUT = V + ISINK VOUT = V – ISOURCE 4 14 16 8 10 12 6 TOTAL SUPPLY VOLTAGE, V + TO V – (V) LTC1047 • TPC05 LTC1047 • TPC04 1047fa 3 LTC1047 TYPICAL PERFOR A CE CHARACTERISTICS CMRR vs Frequency 160 140 120 80 120 VS = ±5V TA = 25°C CMRR (dB) PSRR (dB) 100 80 60 40 20 0 1 10 100 1k FREQUENCY (Hz) 10k 100k Gain, Phase vs Frequency, ± 5V 80 45 900 60 PHASE 90 SAMPLING FREQUENCY, fS (Hz) GAIN (dB) 40 GAIN 20 0 VS = ±5V CL = 50pF –20 103 102 104 105 FREQUENCY (Hz) Sampling Frequency vs Temperature 1000 SAMPLING FREQUENCY, fS (Hz) VS = ±5V 900 100mV STEP 800 700 600 AV = + 1 RL = 100k CL = 50pF VS = ± 5V 10µs/DIV LTC1047 • TPC11 500 50 25 0 75 100 –50 –25 AMBIENT TEMPERATURE, TA (°C) 4 UW PSRR vs Frequency 100 NEGATIVE SUPPLY 60 40 POSITIVE SUPPLY 20 0 1 10 100 1k FREQUENCY (Hz) 10k 100k LTC1047 • TPC06 LTC1047 • TPC07 Sampling Frequency vs Supply Voltage TA = 25°C 800 PHASE SHIFT (DEGREES) 135 700 180 600 225 106 270 500 4 6 8 10 12 14 16 TOTAL SUPPLY VOLTAGE, V + TO V – (V) LTC1047 • TPC09 LTC1047 • TPC08 Small-Signal Transient Response 125 LTC1047 • TPC010 1047fa LTC1047 TYPICAL PERFOR A CE CHARACTERISTICS Large-Signal Transient Response Overload Recovery AV = + 1 RL = 100k CL = 50pF VS = ± 5V TEST CIRCUITS Electrical Characteristics Test Circuit 1k 1M V+ 2 10Ω UW 2 0 Photo –5V 200mV 0 10µs/DIV LTC1047 • TPC12 AV = 100 VS = ± 5V 10ms/DIV LTC1047 • TPC13 – + 8 6 OUTPUT RL 3 1/2 LTC1047 4 V– LTC1047 • TC01 DC to 10Hz Noise Test Circuit 100k 475k 0.01µF – 1/2 LTC1047 6 158k 316k 475k – LT®1012 OUTPUT 3 + 0.01µF 0.01µF + FOR 1Hz NOISE BANDWIDTH, INCREASE ALL CAPACITORS BY A FACTOR OF 10 LTC1047 • TC02 1047fa 5 LTC1047 APPLICATIO S I FOR ATIO Input Considerations Frequently circuits built with parts as precise as the LTC1047 show errors at the output far greater than the designer expects. Rarely is the problem the op amp; more often the surrounding circuitry is causing errors several orders of magnitude greater than those due to the LTC1047. Such obscure effects as leakage between pins, due to residual solder flux and thermocouple effects between the tin/lead solder and the copper PC board traces, can overwhelm the pA-level bias currents and the µV-level offset of the LTC1047. For a more complete description of these types of problems (and some advice on avoiding them), see the LTC1051/LTC1053 data sheet. Input Capacitance The LTC1047 has approximately 12pF of capacitance at each input pin. This will react with large series resistors to form a pole at the input, degrading the LTC1047's phase margin. The problem is especially common with micropower parts like the LTC1047 because high value resistors are often used to minimize power dissipation. As a rule of thumb, bypass feedback resistors larger than 7k with a 20pF capacitor to minimize this effect. 6 U Aliasing Like all sampled data systems, the LTC1047 will alias input signals near its internal sampling frequency. The design includes internal circuitry to minimize this effect; as a result, most applications do not exhibit aliasing problems. For a complete discussion of the correction circuitry and aliasing behavior, refer to the LTC1051/LTC1053 data sheet. Single Supply Operation The LTC1047 is compatible with all single supply applications. It has an input common mode range which includes V –, and an output which will swing within millivolts of the negative power supply. The LTC1047 is guaranteed functional down to 4.75V total supply, allowing it to run from minimum TTL voltage all the way up to 16V. See the Typical Applications section for examples of single supply operation. 1047fa W UU LTC1047 TYPICAL APPLICATIO S Low Offset, Low Drift Instrumentation Amplifier 1M 1k 1k 1M 5V 2 INPUT 0V IS = 50µA VOS = 3µV U – 1/2 LTC1047 1 AV = 1000 VOS = ± 6µV IS = 100µA CMRR ≥ 120dB +IN 6 – + 8 7 OUTPUT –IN 3 + 5 1/2 LTC1047 4 –5V LTC1047 • TA02 Precise DC Full-Wave Rectifier (Absolute Value Circuit) 220k 5V 220k 2 – + 8 1 1N4148 3 1/2 LTC1047 4 5 + 1/2 LTC1047 7 OUTPUT 6 – LTC1047 • TA03 1047fa 7 LTC1047 TYPICAL APPLICATIO S 4mA to 20mA Transducer Amplifier 0.1µF 8 1 2 – + 1/2 3 LTC1047 INPUT 0V TO 1V 1 INITIAL ACCURACY = 3% (LIMITED BY REFERENCE IN LT1120) TRIM R1 FOR 4.00mA WITH 0.00V IN TRIM R2 FOR 20.0mA WITH 1.00V IN 8 U 5 LT1120 4 1M 2 3 7 6 1M TO LOOP 10µF 1000pF + R2 61.9k 1% R1 619K 1% 5 + – 8 7 1k 2N2222 49.9k 1% 6 1/2 LTC1047 4 49.9Ω 1% TO LOOP LTC1047 • TA04 1047fa LTC1047 TYPICAL APPLICATIO S Ultralow Noise Micropower Chopper 0.47µF 5V 5V 5V 75k 100k 0.1µF – 1/2 LTC1047 + 100k +IN 200nV VS = ±5V IS = 150µA 100nV 50nV/DIV –100nV –200nV 0 TIME (SEC) 10 LTC1047 • TA07 U 39k + 20k 1/2 LTC1047 OUT – 0.1µF –5V 100k 50pF –IN 25K147 x 2 10Ω 150k –5V 0.47µF 100k IS = 150µA 0.1Hz TO 10Hz = 95nVP-P AV = 10000 LTC1047 • TA06 0.1Hz to 10Hz Noise (Input Referred) 1047fa 9 LTC1047 PACKAGE DESCRIPTIO .300 – .325 (7.620 – 8.255) .008 – .015 (0.203 – 0.381) +.035 .325 –.015 ( 8.255 +0.889 –0.381 ) INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) NOTE: 1. DIMENSIONS ARE 10 U N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .400* (10.160) MAX 8 7 6 5 .255 ± .015* (6.477 ± 0.381) 1 2 3 4 .130 ± .005 (3.302 ± 0.127) .045 – .065 (1.143 – 1.651) .065 (1.651) TYP .120 (3.048) .020 MIN (0.508) MIN .018 ± .003 (0.457 ± 0.076) N8 1002 .100 (2.54) BSC 1047fa LTC1047 PACKAGE DESCRIPTIO U SW Package 16-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .030 ±.005 TYP N .050 BSC .045 ±.005 .398 – .413 (10.109 – 10.490) NOTE 4 16 15 14 13 12 11 10 9 N .420 MIN .325 ±.005 NOTE 3 .394 – .419 (10.007 – 10.643) N/2 N/2 1 .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737) 0° – 8° TYP 1 2 3 RECOMMENDED SOLDER PAD LAYOUT 2 3 4 5 6 7 8 .093 – .104 (2.362 – 2.642) .037 – .045 (0.940 – 1.143) .005 (0.127) RAD MIN .009 – .013 (0.229 – 0.330) NOTE 3 .016 – .050 (0.406 – 1.270) .050 (1.270) BSC .004 – .012 (0.102 – 0.305) NOTE: 1. DIMENSIONS IN .014 – .019 (0.356 – 0.482) TYP S16 (WIDE) 0502 INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS. THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS 4. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 1047fa Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 11 LTC1047 TYPICAL APPLICATIO U Low Noise, Low Drift Composite Amplifier 5V 5 10k + – 8 7 0.01µF 1000pF 6 1/2 LTC1047 100k 2 – 1/2 LTC1047 1 5V 750Ω 3 1 56Ω 3 + 4 –5V 250k 7 8 6 OUTPUT INPUT + – + – 2 LT ®1012 4 –5V 100k 100Ω VOS = 3µV 0.1Hz TO 10Hz NOISE = 0.7µVP-P IS = 490µA LTC1047 • TA05 1047fa 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● LW/TP 1202 1K REV A • PRINTED IN USA www.linear.com  LINEAR TECHNOLOGY CORPORATION 1992