LT1007/LT1037 Low Noise, High Speed Precision Operational Amplifiers U DESCRIPTION FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ Guaranteed 4.5nV/√Hz 10Hz Noise Guaranteed 3.8nV/√Hz 1kHz Noise 0.1Hz to 10Hz Noise, 60nVP-P Typical Guaranteed 7 Million Min Voltage Gain, RL = 2k Guaranteed 3 Million Min Voltage Gain, RL = 600Ω Guaranteed 25µV Max Offset Voltage Guaranteed 0.6µV/°C Max Drift with Temperature Guaranteed 11V/µs Min Slew Rate (LT1037) Guaranteed 117dB Min CMRR U APPLICATIONS ■ ■ ■ ■ ■ ■ ■ Low Noise Signal Processing Microvolt Accuracy Threshold Detection Strain Gauge Amplifiers Direct Coupled Audio Gain Stages Sine Wave Generators Tape Head Preamplifiers Microphone Preamplifiers , LTC and LT are registered trademarks of Linear Technology Corporation. The LT ®1007/LT1037 series features the lowest noise performance available to date for monolithic operational amplifiers: 2.5nV/√Hz wideband noise (less than the noise of a 400Ω resistor), 1/f corner frequency of 2Hz and 60nV peakto-peak 0.1Hz to 10Hz noise. Low noise is combined with outstanding precision and speed specifications: 10µV offset voltage, 0.2µV/°C drift, 130dB common mode and power supply rejection, and 60MHz gain bandwidth product on the decompensated LT1037, which is stable for closed-loop gains of 5 or greater. The voltage gain of the LT1007/LT1037 is an extremely high 20 million driving a 2kΩ load and 12 million driving a 600Ω load to ±10V. In the design, processing and testing of the device, particular attention has been paid to the optimization of the entire distribution of several key parameters. Consequently, the specifications of even the lowest cost grades (the LT1007C and the LT1037C) have been spectacularly improved compared to equivalent grades of competing amplifiers. The sine wave generator application shown below utilizes the low noise and low distortion characteristics of the LT1037. U TYPICAL APPLICATION 0.1Hz to 10Hz Noise Ultrapure 1kHz Sine Wave Generator 2 – 3 + LT1037 6 OUTPUT C #327 LAMP R C R 1 2πRC R = 1591.5Ω ±0.1% C = 0.1µF ±0.1% f= TOTAL HARMONIC DISTORTION = < 0.0025% NOISE = < 0.0001% AMPLITUDE = ±8V OUTPUT FREQUENCY = 1.000kHz FOR VALUES GIVEN ±0.4% VOLTAGE NOISE (20nV/DIV) 430Ω 1007/37 TA01 0 2 4 6 TIME (SEC) 8 10 1007/37 TA02 1 LT1007/LT1037 W W U W ABSOLUTE MAXIMUM RATINGS Supply Voltage ...................................................... ±22V Input Voltage ............................ Equal to Supply Voltage Output Short-Circuit Duration .......................... Indefinite Differential Input Current (Note 8) ..................... ± 25mA Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec.)................. 300°C Operating Temperature Range LT1007/LT1037AC, C ............................. 0°C to 70°C LT1007/LT1037I ............................... – 40°C to 85°C LT1007/LT1037AM, M ..................... – 55°C to 125°C W U U PACKAGE/ORDER INFORMATION TOP VIEW VOS TRIM TOP VIEW VOS TRIM 1 –IN 2 +IN 3 VOS 8 TRIM – + 7 V– 4 J8 PACKAGE 8-LEAD CERDIP V+ 6 OUT 5 NC –IN 2 TJMAX = 150°C, θJA = 100°C/ W (J8) TJMAX = 100°C, θJA = 130°C/ W (N8) ORDER PART NUMBER LT1037ACJ8 LT1037ACN8 LT1037AMJ8 LT1037CJ8 LT1037CN8 LT1037IN8 LT1037MJ8 – + +IN 3 7 V+ 6 OUT +IN 3 8 – 7 V+ + 6 OUT V– 4 5 NC 4 VOS TRIM 5 NC V – (CASE) H PACKAGE 8-LEAD TO-5 METAL CAN S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 150°C/ W, θJC = 45°C/ W TJMAX = 150°C, θJA = 190°C/ W ORDER PART NUMBER ORDER PART NUMBER N8 PACKAGE 8-LEAD PDIP LT1007ACJ8 LT1007ACN8 LT1007AMJ8 LT1007CJ8 LT1007CN8 LT1007IN8 LT1007MJ8 8 VOS TRIM 1 TOP VIEW VOS 1 TRIM –IN 2 LT1007ACH LT1007AMH LT1007CH LT1007MH LT1037ACH LT1037AMH LT1037CH LT1037MH LT1037CS8 LT1037IS8 LT1007CS8 LT1007IS8 S8 PART MARKING 1037 1037I 1007 1007I ELECTRICAL CHARACTERISTICS VS = ±15V, TA = 25°C, unless otherwise noted. LT1007AC/AM LT1037AC/AM MIN TYP MAX LT1007C/I/M LT1037C/I/M MIN TYP MAX SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage (Note 1) 10 25 20 60 µV ∆VOS ∆Time Long Term Input Offset Voltage Stability (Notes 2, 3) 0.2 1.0 0.2 1.0 µV/Mo IOS Input Offset Current IB Input Bias Current en Input Noise Voltage in 2 UNITS 7 30 12 50 nA ±10 ±35 ±15 ±55 nA 0.1Hz to 10Hz (Notes 3, 5) 0.06 0.13 0.06 0.13 µVP-P Input Noise Voltage Density fO = 10Hz (Notes 3, 4) fO = 1000Hz (Note 3) 2.8 2.5 4.5 3.8 2.8 2.5 4.5 3.8 nV/√Hz nV/√Hz Input Noise Current Density fO = 10Hz (Notes 3, 6) fO = 1000Hz (Notes 3, 6) 1.5 0.4 4.0 0.6 1.5 0.4 4.0 0.6 pA/√Hz pA/√Hz LT1007/LT1037 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER VS = ±15V, TA = 25°C, unless otherwise noted. CONDITIONS LT1007AC/AM LT1037AC/AM MIN TYP MAX LT1007C/I/M LT1037C/I/M MIN TYP MAX 7 5 Input Resistance, Common Mode Input Voltage Range UNITS GΩ ±11.0 ±12.5 ±11.0 ±12.5 V CMRR Common Mode Rejection Ratio VCM = ±11V 117 130 110 126 dB PSRR Power Supply Rejection Ratio VS = ±4V to ±18V 110 130 106 126 dB AVOL Large-Signal Voltage Gain RL ≥ 2k, VO = ±12V RL ≥ 1k, VO = ±10V RL ≥ 600Ω, VO = ±10V 7.0 5.0 3.0 20.0 16.0 12.0 5.0 3.5 2.0 20.0 16.0 12.0 V/µV V/µV V/µV VOUT Maximum Output Voltage Swing RL ≥ 2k RL ≥ 600Ω ±13.0 ±11.0 ±13.8 ±12.5 ±12.5 ±10.5 ±13.5 ±12.5 V V SR Slew Rate LT1007 LT1037 RL ≥ 2k AVCL ≥ 5 1.7 11 2.5 15 1.7 11 2.5 15 V/µs V/µs GBW Gain Bandwidth Product LT1007 LT1037 fO = 100kHz (Note 7) fO = 10kHz (Note 7) (AVCL ≥ 5) 5.0 45 8.0 60 5.0 45 8.0 60 MHz MHz ZO Open-Loop Output Resistance 70 Ω PD Power Dissipation VO = 0V, IO = 0 70 LT1007 LT1037 80 80 120 130 80 85 140 140 mW mW LT1007AC LT1037AC MIN TYP MAX LT1007C LT1037C MIN TYP MAX UNITS VS = ±15V, 0°C ≤ TA ≤ 70°C, unless otherwise noted. SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage (Note 1) ● 20 50 35 110 µV ∆VOS ∆Temp Average Input Offset Drift (Note 9) ● 0.2 0.6 0.3 1.0 µV/°C IOS Input Offset Current ● 10 40 15 70 nA IB Input Bias Current ● ±14 ±45 ±20 ±75 nA Input Voltage Range ● ±10.5 ±11.8 ±10.5 ±11.8 V 126 106 120 dB CMRR Common Mode Rejection Ratio VCM = ±10.5V ● 114 PSRR Power Supply Rejection Ratio VS = ±4.5V to ±18V ● 106 126 102 120 dB AVOL Large-Signal Voltage Gain RL ≥ 2k, VO = ±10V RL ≥ 1k, VO = ±10V ● ● 4.0 2.5 18.0 14.0 2.5 2.0 18.0 14.0 V/µV V/µV VOUT Maximum Output Voltage Swing RL ≥ 2k ● ±12.5 ±13.6 ±12.0 ±13.6 PD Power Dissipation ● 90 144 90 V 160 mW 3 LT1007/LT1037 ELECTRICAL CHARACTERISTICS VS = ±15V, – 40°C ≤ TA ≤ 85°C, unless otherwise noted. LT1007I/LT1037I MIN TYP MAX SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage (Note 1) ● 40 125 µV ∆VOS ∆Temp Average Input Offset Drift (Note 9) ● 0.3 1.0 µV/°C IOS Input Offset Current ● 20 80 nA IB Input Bias Current ● ±25 ±90 nA ● ±10 ±11.7 V CMRR Common Mode Rejection Ratio VCM = ±10.5V ● 105 120 dB PSRR Power Supply Rejection Ratio VS = ±4.5V to ±18V ● 101 120 dB AVOL Large-Signal Voltage Gain RL ≥ 2k, VO = ±10V RL ≥ 1k, VO = ±10V ● ● 2.0 1.5 15.0 12.0 V/µV V/µV VOUT Maximum Output Voltage Swing RL ≥ 2k ● ±12.0 ±13.6 V PD Power Dissipation Input Voltage Range 95 UNITS 165 mW LT1007M/LT1037M MIN TYP MAX UNITS ● VS = ±15V, – 55°C ≤ TA ≤ 125°C, unless otherwise noted. LT1007AM/LT1037AM MIN TYP MAX SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage (Note 1) ● 25 60 50 160 µV ∆VOS ∆Temp Average Input Offset Drift (Note 9) ● 0.2 0.6 0.3 1.0 µV/°C IOS Input Offset Current ● 15 50 20 85 nA IB Input Bias Current ● ±20 ±60 ±35 ±95 nA Input Voltage Range ● ±10.3 ±11.5 ±10.3 ±11.5 V CMRR Common Mode Rejection Ratio VCM = ±10.3V ● 112 126 104 120 dB PSRR Power Supply Rejection Ratio VS = ±4.5V to ±18V ● 104 126 100 120 dB AVOL Large-Signal Voltage Gain RL ≥ 2k, VO = ±10V RL ≥ 1k, VO = ±10V ● ● 3.0 2.0 14.0 10.0 2.0 1.5 14.0 10.0 V/µV V/µV VOUT Maximum Output Voltage Swing RL ≥ 2k ● ±12.5 ± 13.5 ±12.0 ±13.5 PD Power Dissipation The ● denotes the specifications which apply over the full operating temperature range. For MIL-STD components, please refer to LTC 883C data sheet for test listing and parameters. Note 1: Input Offset Voltage measurements are performed by automatic test equipment approximately 0.5 seconds after application of power. AM and AC grades are guaranteed fully warmed up. Note 2: Long Term Input Offset Voltage Stability refers to the average trend line of Offset Voltage vs Time over extended periods after the first 30 days of operation. Excluding the initial hour of operation, changes in VOS during the first 30 days are typically 2.5µV. Refer to typical performance curve. Note 3: This parameter is tested on a sample basis only. 4 ● 100 150 100 V 170 mW Note 4: 10Hz noise voltage density is sample tested on every lot. Devices 100% tested at 10Hz are available on request. Note 5: See the test circuit and frequency response curve for 0.1Hz to 10Hz tester in the Applications Information section. Note 6: See the test circuit for current noise measurement in the Applications Information section. Note 7: This parameter is guaranteed by design and is not tested. Note 8: The inputs are protected by back-to-back diodes. Current limiting resistors are not used in order to achieve low noise. If differential input voltage exceeds ±0.7V, the input current should be limited to 25mA. Note 9: The Average Input Offset Drift performance is within the specifications unnulled or when nulled with a pot having a range of 8kΩ to 20kΩ. LT1007/LT1037 U W TYPICAL PERFORMANCE CHARACTERISTICS 10Hz Voltage Noise Distribution 100 140 100 VS = ±15V TA = 25°C RMS VOLTAGE NOISE DENSITY (nV/√Hz) VS = ±15V TA = 25°C 497 UNITS MEASURED FROM SIX RUNS 120 NUMBER OF UNITS 0.02Hz to 10Hz RMS Noise. Gain = 50,000 (Measured on HP3582 Spectrum Analyzer) Voltage Noise vs Frequency 80 60 40 20 30 10 MAXIMUM 3 1 0.1 0 0 1 7 8 9 4 5 6 2 3 VOLTAGE NOISE DENSITY (nV/√Hz) TYPICAL 1/f CORNER = 2Hz 10 1 10 100 FREQUENCY (Hz) 1000 MARKER AT 2Hz ( = 1/f CORNER) = 1007/37 G03 1007/37 G02 1007/37 G01 0.01Hz to 1Hz Peak-to-Peak Noise Total Noise vs Source Resistance Voltage Noise vs Temperature 5 1000 TOTAL NOISE DENSITY (nV/√Hz) VOLTAGE NOISE (20nV/DIV) R RMS VOLTAGE NOISE DENSITY (nV/√Hz) VS = ±15V TA = 25°C R SOURCE RESISTANCE = 2R 100 AT 1kHz AT 10Hz 10 RESISTOR NOISE ONLY 1 0 20 40 60 TIME (SEC) 80 0.1 100 1 10 SOURCE RESISTANCE (kΩ) 1007/37 G04 1 TYPICAL 0.1 1 10k 1007/37 G07 50 25 0 75 TEMPERATURE (°C) –25 125 100 Voltage Noise vs Supply Voltage 5 1 0.1 TA = 25°C 4 0.1 1 10 BANDWIDTH (kHz) 100 1007/37 G08 AT 10Hz 3 AT 1kHz 2 1 0 0.01 100 1k FREQUENCY (Hz) AT 1kHz 2 1007/37 G06 RMS VOLTAGE NOISE DENSITY (nV/√Hz) RMS VOLTAGE NOISE (µV) RMS NOISE DENSITY (pA/√Hz) MAXIMUM 10 AT 10Hz 3 0 –50 100 10 1/f CORNER = 120Hz 4 Wideband Voltage Noise (0.1Hz to Frequency Indicated) 10 0.3 VS = ±15V 1007/37 G05 Current Noise vs Frequency 3 179µV/√Hz nV = 3.59 50,000 √Hz 0 5 15 20 10 SUPPLY VOLTAGE (±V) 25 1007/37 G09 5 LT1007/LT1037 U W TYPICAL PERFORMANCE CHARACTERISTICS Voltage Gain vs Frequency 25 120 100 80 LT1037 LT1007 60 40 20 RL = 2k –1 20 15 RL = 600Ω 10 0 RL = 2k –1 1 0 5 0 10 100 1k 10k 100k 1M 10M 100M FREQUENCY (Hz) 5 0 15 20 10 SUPPLY VOLTAGE (±V) 1007/37 G10 VOLTAGE GAIN (V/µV) OPEN-LOOP VOLTAGE GAIN (V/µV) 15 10 RL = 1k 15 RL = 600Ω 10 VS = ±15V VOUT = ±10V VOUT = ±8V FOR TA ≥ 100°C AND RL = 600Ω 0 –50 10 50 25 0 75 TEMPERATURE (°C) 100 4 30 OFFSET VOLTAGE (µV) 5 0.2µV/MONTH 0 –5 DUAL-IN-LINE PACKAGE PLASTIC (N8) OR CERDIP (J8) 2 0 1 3 4 2 TIME AFTER POWER ON (MINUTES) 5 1007/37 G15 Supply Current vs Supply Voltage 4 VS = ±15V LT1007/LT1037 LT1007A/LT1037A SUPPLY CURRENT (mA) 40 20 10 0 –10 –20 3 125°C 2 –55°C 25°C 1 –30 0.2µV/MONTH TREND LINE 8 METAL CAN (H) PACKAGE 125 50 6 4 TIME (MONTHS) 6 Offset Voltage Drift with Temperature of Representative Units 10 2 8 1007/37 G14 Long Term Stability of Four Representative Units 0 VS = ±15V TA = 25°C 0 –25 1007/37 G13 OFFSET VOLTAGE CHANGE (µV) Warm-Up Drift RL = 2k 5 5 –40 10 1007/37 G16 6 1007/37 G12 10 20 1 0.3 3 LOAD RESISTANCE (kΩ) –10 Voltage Gain vs Temperature 20 –10 –5 0 5 10 15 OUTPUT VOLTAGE (V) MEASURED ON TEKTRONIX 178 LINEAR IC TESTER 25 VS = ±15V TA = 25°C 0 0.1 –15 1007/37 G11 Voltage Gain vs Load Resistance 25 25 CHANGE IN OFFSET VOLTAGE (µV) –20 0.01 0.1 1 1 RL = 600Ω VS = ±15V TA = 25°C 0 INPUT VOLTAGE (µV) OPEN-LOOP VOLTAGE GAIN (V/µV) 140 TA = 25°C INPUT VOLTAGE (µV) VS = ±15V TA = 25°C RL = 2k 160 VOLTAGE GAIN (dB) Voltage Gain, RL = 2k and 600Ω Voltage Gain vs Supply Voltage 180 –50 –50 0 –25 50 25 0 75 TEMPERATURE (°C) 100 125 1007/37 G17 0 10 5 15 SUPPLY VOLTAGE (±V) 20 1007/37 G18 LT1007/LT1037 U W TYPICAL PERFORMANCE CHARACTERISTICS Common Mode Rejection vs Frequency Common Mode Limit vs Temperature V+ 140 VS = ±15V VCM = ±10V TA = 25°C 100 LT1037 LT1007 80 60 –3 –4 +4 +3 V – = –3V TO –20V +2 104 105 106 FREQUENCY (Hz) V 107 – –50 –25 50 25 0 75 TEMPERATURE (°C) 100 1007/37 G19 LT1007M LT1037M 10 Output Swing vs Load Resistance 25 50 75 0 TEMPERATURE (°C) 50 12 40 30 LT1007M LT1037M 20 0 25 50 75 –75 –50 –25 0 TEMPERATURE (°C) 100 125 10 AV = 1000 1 0.1 SHORT-CIRCUIT CURRENT (mA) SINKING SOURCING OUTPUT IMPEDANCE (Ω) POSITIVE SUPPLY AV = 1000 AV = 1 AV = 5 0.01 LT1007 LT1037 20 102 103 104 105 106 107 108 FREQUENCY (Hz) 1195 G25 10k 50 VS = ±15V TA = 25°C IOUT = 1mA 140 60 300 3k 1k LOAD RESISTANCE (Ω) Output Short-Circuit Current vs Time 100 TA = 25°C NEGATIVE SUPPLY VS = ±15V TA = 25°C 1007/37 G24 Closed-Loop Output Impedance 160 10 6 1007/37 G23 PSRR vs Frequency 100 NEGATIVE SWING 9 0 100 100 125 1007/37 G22 120 POSITIVE SWING 3 LT1007AM LT1037AM 0 1 15 15 10 LT1007AM LT1037AM 0 10 –5 0 5 –10 COMMON MODE INPUT VOLTAGE (V) 1007/37 G21 OUTPUT SWING (V) INPUT OFFSET CURRENT (nA) INPUT BIAS CURRENT (nA) 30 40 DEVICE WITH NEGATIVE INPUT CURRENT –10 VS = ±15V 40 80 20V ≈ 7G 3nA RCM = –5 Input Offset Current vs Temperature VS = ±15V –50 –25 VS = ±15V TA = 25°C 0 –20 –15 125 60 20 5 1007/37 G20 Input Bias Current vs Temperature 50 DEVICE WITH POSITIVE INPUT CURRENT 10 –15 +1 40 103 POWER SUPPLY REJECTION RATIO (dB) 15 V + = 3V TO 20V –2 INPUT BIAS CURRENT (nA) 120 20 –1 COMMON MODE LIMIT (V) REFERRED TO POWER SUPPLY COMMON MODE REJECTION RATIO (dB) Input Bias Current Over the Common Mode Range 0.001 10 100 10k 1k FREQUENCY (Hz) 100k 1M 1007/37 G26 40 30 – 55°C 25°C 20 125°C 10 0 VS = ±15V –10 –20 125°C –30 25°C –40 – 55°C –50 2 0 1 3 TIME FROM OUTPUT SHORT TO GROUND (MINUTES) 1007/37 G27 7 LT1007/LT1037 U W TYPICAL PERFORMANCE CHARACTERISTICS LT1037 Small-Signal Transient Response LT1037 Phase Margin, Gain Bandwidth Product, Slew Rate vs Temperature 0V 0V – 50mV – 10V PHASE MARGIN (DEG) 10V 20 VS = ±15V CL = 100pF 60 70 PHASE MARGIN 50 60 AVCL = 5 VS = ±15V CL = 15pF GBW AVCL = 5 VS = ±15V 1007/37 G29 1007/37 G28 50 SLEW 15 10 –50 –25 50 25 0 75 TEMPERATURE (°C) GAIN BANDWIDTH PROCUCT, fO = 10kHz (MHz) 50mV 70 SLEW RATE (V/µs) LT1037 Large-Signal Response 125 100 1007/37 G30 LT1037 Gain, Phase Shift vs Frequency 20 150 GAIN 160 AV = 5 170 10 100 110 120 130 20 PHASE 140 GAIN 10 150 160 170 0 180 0 0.1 1 10 FREQUENCY (MHz) 190 100 SLEW RATE (V/µs) PHASE MARGIN (DEG) 140 30 VOLTAGE GAIN (dB) 130 PHASE 30 VS = ±15V TA = 25°C CL = 100pF PHASE SHIFT (DEG) 120 PHASE SHIFT (DEG) VOLTAGE GAIN (dB) 40 70 90 40 180 –10 0.1 1007/37 G31 60 PHASE MARGIN 9 50 GBW 8 3 SLEW 7 2 1 –50 190 100 1 10 FREQUENCY (MHz) VS = ±15V CL = 100pF –25 50 25 0 75 TEMPERATURE (°C) LT1007 Small-Signal Transient Response 125 100 1007/37 G32 GAIN BANDWIDTH PROCUCT, fO = 100kHz (MHz) 90 VS = ±15V 100 TA = 25°C CL = 100pF 110 50 LT1007 Phase Margin, Gain Bandwidth Product, Slew Rate vs Temperature LT1007 Gain, Phase Shift vs Frequency 1007/37 G33 Maximum Undistorted Output vs Frequency LT1007 Large-Signal Response 5V 50mV 0V 0V – 50mV – 5V AVCL = 1 VS = ±15V CL = 15pF AVCL = – 1 VS = ±15V 1007/37 G34 1007/37 G35 PEAK-TO-PEAK OUTPUT VOLTAGE (V) 28 VS = ±15V TA = 25°C 24 20 16 LT1007 12 LT1037 8 4 0 1k 10k 100k 1M FREQUENCY (Hz) 10M 1007/37 G36 8 LT1007/LT1037 U U W U APPLICATIONS INFORMATION General Offset Voltage and Drift The LT1007/LT1037 series devices may be inserted directly into OP-07, OP-27, OP-37 and 5534 sockets with or without removal of external compensation or nulling components. In addition, the LT1007/LT1037 may be fitted to 741 sockets with the removal or modification of external nulling components. Thermocouple effects, caused by temperature gradients across dissimilar metals at the contacts to the input terminals, can exceed the inherent drift of the amplifier unless proper care is exercised. Air currents should be minimized, package leads should be short, the two input leads should be close together and maintained at the same temperature. Offset Voltage Adjustment The input offset voltage of the LT1007/LT1037 and its drift with temperature, are permanently trimmed at wafer testing to a low level. However, if further adjustment of VOS is necessary, the use of a 10kΩ nulling potentiometer will not degrade drift with temperature. Trimming to a value other than zero creates a drift of (VOS / 300)µV/°C, e.g., if VOS is adjusted to 300µV, the change in drift will be 1µV/°C (Figure 1). The circuit shown to measure offset voltage is also used as the burn-in configuration for the LT1007/LT1037, with the supply voltages increased to ±20V (Figure 3). 50k* 15V 2 100Ω* 3 The adjustment range with a 10kΩ pot is approximately ±2.5mV. If less adjustment range is needed, the sensitivity and resolution of the nulling can be improved by using a smaller pot in conjunction with fixed resistors. The example has an approximate null range of ±200µV (Figure 2). 10k 15V – 2 1 8 LT1007 INPUT 7 6 OUTPUT +LT1037 3 4 –15V 1007/37 F01 Figure 1. Standard Adjustment 1k 15V 4.7k – 7 6 LT1007 LT1037 + 4 50k* –15V VOUT VOUT = 1000VOS *RESISTORS MUST HAVE LOW THERMOELECTRIC POTENTIAL 1007/37 F03 Figure 3. Test Circuit for Offset Voltage and Offset Voltage Drift with Temperature Unity-Gain Buffer Application (LT1007 Only) When RF ≤ 100Ω and the input is driven with a fast, largesignal pulse (>1V), the output waveform will look as shown in the pulsed operation diagram (Figure 4). During the fast feedthrough-like portion of the output, the input protection diodes effectively short the output to the input and a current, limited only by the output short-circuit protection, will be drawn by the signal generator. With RF ≥ 500Ω, the output is capable of handling the current requirements (IL ≤ 20mA at 10V) and the amplifier stays in its active mode and a smooth transition will occur. 4.7k 2 3 – 1 RF 8 LT1007 LT1037 7 6 OUTPUT – + 2.8V/µs OUTPUT 4 + –15V LT1007 1007/37 F02 Figure 2. Improved Sensitivity Adjustment 1007/37 F04 Figure 4. Pulsed Operation 9 LT1007/LT1037 U W U U APPLICATIONS INFORMATION As with all operational amplifiers when RF > 2k, a pole will be created with RF and the amplifier’s input capacitance, creating additional phase shift and reducing the phase margin. A small capacitor (20pF to 50pF) in parallel with RF will eliminate this problem. Noise Testing The 0.1Hz to 10Hz peak-to-peak noise of the LT1007/ LT1037 is measured in the test circuit shown (Figure 5a). The frequency response of this noise tester (Figure 5b) indicates that the 0.1Hz corner is defined by only one zero. The test time to measure 0.1Hz to 10Hz noise should not exceed ten seconds, as this time limit acts as an additional zero to eliminate noise contributions from the frequency band below 0.1Hz. Measuring the typical 60nV peak-to-peak noise performance of the LT1007/LT1037 requires special test precautions: electric effects in excess of a few nanovolts, which would invalidate the measurements. 3. Sudden motion in the vicinity of the device can also “feedthrough” to increase the observed noise. A noise voltage density test is recommended when measuring noise on a large number of units. A 10Hz noise voltage density measurement will correlate well with a 0.1Hz to 10Hz peak-to-peak noise reading since both results are determined by the white noise and the location of the 1/f corner frequency. Current noise is measured in the circuit shown in Figure 6 and calculated by the following formula: 1/ 2 2 2 eno − 130nV • 101 in = 1MΩ 101 ) ( ) ( ( )( ) 1. The device should be warmed up for at least five minutes. As the op amp warms up, its offset voltage changes typically 3µV due to its chip temperature increasing 10°C to 20°C from the moment the power supplies are turned on. In the ten-second measurement interval these temperature-induced effects can easily exceed tens of nanovolts. 100k 100Ω 500k – 500k +LT1037 LT1007 eno 1007/37 F06 2. For similar reasons, the device must be well shielded from air currents to eliminate the possibility of thermo- Figure 6 0.1µF 100 90 100k 80 – * LT1007 LT1037 + 2k + 4.3k SCOPE ×1 RIN = 1M LT1001 4.7µF – VOLTAGE GAIN = 50,000 *DEVICE UNDER TEST NOTE: ALL CAPACITOR VALUES ARE FOR NONPOLARIZED CAPACITORS ONLY 22µF 2.2µF 110k GAIN (dB) 10Ω 70 60 50 100k 40 24.3k 0.1µF 1007/37 F05a 30 0.01 0.1 1 10 FREQUENCY (Hz) 100 1007/37F05b Figure 5a. 0.1Hz to 10Hz Noise Test Circuit 10 Figure 5b. 0.1Hz to 10Hz Peak-toPeak Noise Tester Frequency Response LT1007/LT1037 U U W U APPLICATIONS INFORMATION The LT1007/LT1037 achieve their low noise, in part, by operating the input stage at 120µA versus the typical 10µA of most other op amps. Voltage noise is inversely proportional while current noise is directly proportional to the square root of the input stage current. Therefore, the LT1007/LT1037’s current noise will be relatively high. At low frequencies, the low 1/f current noise corner frequency (≈120Hz) minimizes current noise to some extent. In most practical applications, however, current noise will not limit system performance. This is illustrated in the Total Noise vs Source Resistance plot in the Typical Performance Characteristics section, where: Total Noise = [(voltage noise)2 + (current noise • RS)2 + (resistor noise)2]1/2 Three regions can be identified as a function of source resistance: (i) RS ≤ 400Ω. Voltage noise dominates (ii) 400Ω ≤ RS ≤ 50k at 1kHz 400Ω ≤ RS ≤ 8k at 10Hz (iii) RS > 50k at 1kHz RS > 8k at 10Hz } } Resistor noise dominates Current noise dominates Clearly the LT1007/LT1037 should not be used in region (iii), where total system noise is at least six times higher than the voltage noise of the op amp, i.e., the low voltage noise specification is completely wasted. U TYPICAL APPLICATIONS Gain Error vs Frequency Closed-Loop Gain = 1000 Gain 1000 Amplifier with 0.01% Accuracy, DC to 5Hz 340k 1% 15k 5% 20k TRIM 1 TYPICAL PRECISION OP AMP 15V 2 – 7 6 3 + LT1037 4 INPUT OUTPUT RN60C FILM RESISTORS –15V THE HIGH GAIN AND WIDE BANDWIDTH OF THE LT1037 (AND LT1007) IS USEFUL IN LOW FREQUENCY, HIGH CLOSED-LOOP GAIN AMPLIFIER APPLICATIONS. A TYPICAL PRECISION OP AMP MAY HAVE AN OPEN-LOOP GAIN OF ONE MILLION WITH 500kHz BANDWIDTH. AS THE GAIN ERROR PLOT SHOWS, THIS DEVICE IS CAPABLE OF 0.1% AMPLIFYING ACCURACY UP TO 0.3Hz ONLY. EVEN INSTRUMENTATION RANGE SIGNALS CAN VARY AT A FASTER RATE. THE LT1037’S “GAIN PRECISION-BANDWIDTH PRODUCT” IS 200 TIMES HIGHER AS SHOWN. GAIN ERROR (%) 365Ω 1% 0.1 LT1007 LT1037 0.01 GAIN ERROR = CLOSED-LOOP GAIN OPEN-LOOP GAIN 0.001 0.1 1 10 FREQUENCY (Hz) 100 1007/37 TA03 11 LT1007/LT1037 U TYPICAL APPLICATIONS Precision Amplifier Drives 300Ω Load to ±10V Microvolt Comparator with Hysteresis 100M 5% 20k 5% 340k 1% 15V 10k TRIM 365Ω 1% 7 3 INPUT + 8 6 LT1007 2 – 15k 1% 2 – 3 + OUTPUT LT1007 365Ω 1% 4 2 – 3 INPUT OFFSET VOLTAGE IS TYPICALLY CHANGED LESS THAN 5µV DUE TO THE FEEDBACK. + 15Ω 5% 15Ω 5% 6 –15V POSITIVE FEEDBACK TO ONE OF THE NULLING TERMINALS CREATES APPROXIMATELY 5µV OF HYSTERESIS. OUTPUT CAN SINK 16mA. 6 OUTPUT ±10V LT1037 RL 300Ω INPUT 1007/37 TA04 THE ADDITION OF THE LT1007 DOUBLES THE AMPLIFIER’S OUTPUT DRIVE TO ±33mA. GAIN ACCURACY IS 0.02%, SLIGHTLY DEGRADED COMPARED TO ABOVE BECAUSE OF SELF-HEATING OF THE LT1037 UNDER LOAD. Infrared Detector Preamplifier 15V + 10µF 10Ω 100µF 1k + 33Ω CHOPPED DETECTOR OUTPUT 2N2219A + 100µF 50mA 15V 267Ω* 100µF 3 + IR RADIATION OPTICAL CHOPPER PHOTOCONDUCTIVE INFRARED DETECTOR HgCdTe type INFRA-RED ASSOCIATES, INC. 392Ω* + 7 LT1007 2 – 4 –15V 6 OUTPUT TO DEMODULATOR 392k* SYNCHRONOUS 13Ω AT 77°K 392Ω* *1% METAL FILM 1007/37 TA08 12 1007/37 TA05 LT1007/LT1037 U TYPICAL APPLICATIONS Phono Preamplifier Tape Head Amplifier 4.99k 100Ω 2 – 0.01µF 7.87k 15V 316k 100k 7 0.033µF 100Ω 6 100pF 3 + 47k 2 – OUTPUT LT1037 4 0.01µF TAPE HEAD INPUT ALL RESISTORS METAL FILM 3 + LT1037 6 OUTPUT ALL RESISTORS METAL FILM –15V 1007/37 TA07 MAG PHONO INPUT 1007/37 TA06 W W SI PLIFIED SCHE ATIC 8 1 V+ 7 Q4 Q3 Q7 450µA 3.4k 3.4k 750µA 240µA Q28 Q8 Q6 V – Q5 130pF 17k 17k 1.2k 1.2k C1 Q18 Q9 Q27 Q17 Q10 20Ω Q19 V– NONINVERTING INPUT (+) 750Ω Q20 Q25 OUTPUT 6 Q26 Q1A 3 Q2A Q1B 200Ω Q2B V + 80pF Q13 20Ω 20pF Q30 2 V+ Q22 Q11 INVERTING INPUT (–) Q12 Q15 Q16 Q23 Q29 Q24 500µA C1 = 110pF FOR LT1007 C1 = 12pF FOR LT1037 240µA 120µA 200Ω 6k 200Ω 6k 50Ω V– 4 1007/37 SD 13 LT1007/LT1037 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. H Package 8-Lead TO-5 Metal Can (0.200 PCD) (LTC DWG # 05-08-1320) 0.335 – 0.370 (8.509 – 9.398) DIA 0.305 – 0.335 (7.747 – 8.509) 0.040 (1.016) MAX 0.050 (1.270) MAX SEATING PLANE 0.165 – 0.185 (4.191 – 4.699) GAUGE PLANE 0.010 – 0.045* (0.254 – 1.143) REFERENCE PLANE 0.500 – 0.750 (12.700 – 19.050) 0.016 – 0.021** (0.406 – 0.533) 0.027 – 0.045 (0.686 – 1.143) 45°TYP 0.027 – 0.034 (0.686 – 0.864) 0.200 (5.080) TYP 0.110 – 0.160 (2.794 – 4.064) INSULATING STANDOFF *LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND 0.045" BELOW THE REFERENCE PLANE 0.016 – 0.024 **FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 – 0.610) H8(TO-5) 0.200 PCD 0595 J8 Package 8-Lead CERDIP (Narrow 0.300, Hermetic) (LTC DWG # 05-08-1110) CORNER LEADS OPTION (4 PLCS) 0.023 – 0.045 (0.584 – 1.143) HALF LEAD OPTION 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION 0.005 (0.127) MIN 0.405 (10.287) MAX 8 7 6 5 0.025 (0.635) RAD TYP 0.220 – 0.310 (5.588 – 7.874) 1 0.300 BSC (0.762 BSC) 2 3 4 0.200 (5.080) MAX 0.015 – 0.060 (0.381 – 1.524) 0.008 – 0.018 (0.203 – 0.457) 0.385 ± 0.025 (9.779 ± 0.635) 0° – 15° 0.045 – 0.068 (1.143 – 1.727) 0.014 – 0.026 (0.360 – 0.660) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS. 14 0.125 3.175 0.100 ± 0.010 MIN (2.540 ± 0.254) J8 0694 LT1007/LT1037 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.400* (10.160) MAX 8 7 6 5 1 2 3 4 0.255 ± 0.015* (6.477 ± 0.381) 0.300 – 0.325 (7.620 – 8.255) 0.065 (1.651) TYP 0.009 – 0.015 (0.229 – 0.381) ( 0.130 ± 0.005 (3.302 ± 0.127) 0.045 – 0.065 (1.143 – 1.651) 0.125 (3.175) MIN 0.005 (0.127) MIN +0.025 0.325 –0.015 +0.635 8.255 –0.381 ) 0.018 ± 0.003 (0.457 ± 0.076) 0.100 ± 0.010 (2.540 ± 0.254) 0.015 (0.380) MIN N8 0695 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) S8 Package 8-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.189 – 0.197* (4.801 – 5.004) 8 7 6 5 0.150 – 0.157** (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) 1 0.010 – 0.020 × 45° (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 2 3 4 0.053 – 0.069 (1.346 – 1.752) 0.004 – 0.010 (0.101 – 0.254) 0°– 8° TYP 0.016 – 0.050 0.406 – 1.270 *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 0.014 – 0.019 (0.355 – 0.483) 0.050 (1.270) BSC 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. SO8 0695 15 LT1007/LT1037 U TYPICAL APPLICATIONS Strain Gauge Signal Conditioner with Bridge Excitation 7.5V 5k 2.5V 3 7 + 6 LT1009 2 LT1007 – 4 –7.5V REFERENCE OUT 350Ω BRIDGE 15V 3 301k* – ZERO TRIM 10k 2 + – 6 4 7 LT1007 4 –7.5V OUTPUT 0V TO 10V 1µF 301k* GAIN TRIM 50k 499Ω* –15V 6 3 7 LT1007 7.5V 2 + *RN60C FILM RESISTOR THE LT1007 IS CAPABLE OF PROVIDING EXCITATION CURRENT DIRECTLY TO BIAS THE 350Ω BRIDGE AT 5V. WITH ONLY 5V ACROSS THE BRIDGE (AS OPPOSED TO THE USUAL 10V) TOTAL POWER DISSIPATION AND BRIDGE WARM-UP DRIFT IS REDUCED. THE BRIDGE OUTPUT SIGNAL IS HALVED, BUT THE LT1007 CAN AMPLIFY THE REDUCED SIGNAL ACCURATELY. 1007/37 TA09 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1028 Ultralow Noise Precision Op Amp Lowest Noise 0.85mV/√Hz LT1115 Ultralow Noise, Low distortion Audio Op Amp 0.002% THD, Max Noise 1.2mV/√Hz LT1124/LT1125 Dual/Quad Low Noise, High Speed Precision Op Amps Similar to LT1007 LT1126/LT1127 Dual/Quad Decompensated Low Noise, High Speed Precision Op Amps Similar to LT1037 LT1498/LT1499 10MHz, 5V/µs, Dual/Quad Rail-to-Rail Input and Output Precision C-LoadTM Op Amps C-Load is a trademark of Linear Technology Corporation. 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408)432-1900 FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com 100737fa LT/TP 0297 5K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1985