LM363 Precision Instrumentation Amplifier

LM363 Precision Instrumentation Amplifier April 1991 LM363 Precision Instrumentation Amplifier General Description The LM363 is a monolithic true instrumentation amplifier It requires no external parts for fixed gains of 10 100 and 1000 High precision is attained by on-chip trimming of offset voltage and gain A super-beta bipolar input stage gives very low input bias current and voltage noise extremely low offset voltage drift and high common-mode rejection ratio A two-stage amplifier design yields an open loop gain of 10 000 000 and a gain bandwidth product of 30 MHz yet remains stable for all closed loop gains The LM363 operates with supply voltages from g5V to g18V with only 1 5 mA current drain The LM363’s low voltage noise low offset voltage and offset voltage drift make it ideal for amplifying low-level lowimpedance transducers At the same time its low bias current and high input impedance (both common-mode and differential) provide excellent performance at high impedance levels These features along with its ultra-high common-mode rejection allow the LM363 to be used in the most demanding instrumentation amplifier applications replacing expensive hybrid module or multi-chip designs Because the LM363 is internally trimmed precision external resistors and their associated errors are eliminated The 16-pin dual-in-line package provides pin-strappable gains of 10 100 or 1000 Its twin differential shield drivers eliminate bandwidth loss due to cable capacitance Compensation pins allow overcompensation to reduce bandwidth and output noise or to provide greater stability with capacitive loads Separate output force sense and reference pins permit gains between 10 and 10 000 to be programmed using external resistors On the 8-pin metal can package gain is internally set at 10 100 or 500 but may be increased with external resistors The shield driver and offset adjust pins are omitted on the 8-pin versions The LM363 is rated for 0 C to 70 C Features Y Y Y Y Y Y Y Y Offset and gain pretrimmed 12 nV 0Hz input noise (G e 500 1000) 130 dB CMRR typical (G e 500 1000) 2 nA bias current typical No external parts required Dual shield drivers Can be used as a high performance op amp Low supply current (1 5 mA typ) Typical Connections 8-Pin Package 16-Pin Package G e 10 2 3 4 open G e 100 3–4 shorted G e 1000 2–4 shorted TL H 5609 – 33 TL H 5609 – 1 Connection Diagrams Metal Can Package 16-Pin Dual-In-Line Package Order Number LM363H-10 LM363H-100 or LM363H-500 See NS Package Number H08C C1995 National Semiconductor Corporation TL H 5609 TL H 5609 – 2 Order Number 363D See NS Package Number D16C RRD-B30M115 Printed in U S A Absolute Maximum Ratings (Note 5) If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage Differential Input Voltage Input Current g18V g10V g20 mA Input Voltage Reference and Sense Voltage Lead Temp (Soldering 10 sec ) ESD rating to be determined Equal to Supply Voltage g25V 300 C LM363 Electrical Characteristics (Notes 1 and 2) LM363 Parameter Conditions Typ Tested Limit (Note 3) Design Limit (Note 4) Units FIXED GAIN (8-PIN) Input Offset Voltage G e 500 G e 100 G e 10 G e 500 G e 100 G e 10 G e 500 G e 100 G e 10 30 50 05 1 2 20 01 0 07 0 05 08 07 06 150 250 25 400 700 6 4 8 75 09 08 07 mV mV mV mV C mV C mV C % % % Input Offset Voltage Drift Gain Error (g10V Swing 2 kX Load) PROGRAMMABLE GAIN (16-PIN) Input Offset Voltage G e 1000 G e 100 G e 10 G e 1000 G e 100 G e 10 G e 1000 G e 100 G e 10 50 100 1 1 2 10 20 01 06 250 450 35 500 900 8 5 10 100 mV mV mV mV C mV C mV C % % % Input Offset Voltage Drift Gain Error (g10V Swing 2 kX Load) FIXED GAIN AND PROGRAMMABLE Gain Temperature Coefficient 30 07 20 35 08 23 G e 1000 G e 500 G e 100 10 G e 10 100 G e 500 1000 40 20 10 0 01 0 01 0 03 0 05 0 04 0 06 ppm C ppm C ppm C % % Gain Non-Linearity (g10V Swing 2 kX Load) 2 LM363 Electrical Characteristics (Continued) (Notes 1 and 2) LM363 Parameter Conditions Typ 130 120 105 130 120 100 120 106 86 2 1 100 G e 1000 500 G e 100 G e 10 b 11V s VCM s 13V Tested Limit (Note 3) 114 94 90 110 100 85 100 85 70 10 3 8 Design Limit (Note 4) 104 84 80 100 95 78 90 75 60 20 5 Units Common-Mode Rejection Ratio (b10VsVCMs10V) Positive Supply Rejection Ratio (5V to 15V) Negative Supply Rejection Ratio (b5V to b15V) Input Bias Current Input Offset Current Common-Mode Input Resistance Differential Mode Input Resistance Input Offset Current Change Reference and Sense Resistance Open Loop Gain Supply Current G e 1000 500 G e 100 G e 10 G e 1000 500 G e 100 G e 10 G e 1000 500 G e 100 G e 10 dB dB dB dB dB dB dB dB dB nA nA GX GX GX GX 02 2 20 20 50 100 30 80 10 12 16 1 24 28 30 34 300 27 83 pa V kX kX kX V mV mA mA Min Max GCL e 1000 500 Positive Negative Note 1 These conditions apply unless otherwise noted V a e 15V Vb eb 15V VCM e 0V RL e 2 kX reference pin grounded sense pin connected to output and Tj e 25 C Note 2 Boldface limits are guaranteed over full temperature range Operating ambient temperature range is 0 C to 70 C for the LM363 Note 3 Guaranteed and 100% production tested Note 4 Guaranteed but not 100% tested These limits are not used in determining outgoing quality levels Note 5 Maximum rated junction temperature is 100 C for the LM363 Thermal resistance junction to ambient is 150 C W for the TO-99(H) package and 100 C W for the ceramic DIP (D) 3 Typical Performance Characteristics TA e 25 C Parameter Input Voltage Noise rms 1 kHz Input Voltage Noise (Note 6) Input Current Noise rms 1 kHz Input Current Noise (Note 6) Bandwidth Slew Rate Settling Time 0 1% of 10V Offset Voltage Warm-Up Drift (Note 7) Offset Voltage Stability (Note 8) Gain Stability (Note 8) Note 6 Measured for 100 seconds in a 0 01 Hz to 10 Hz bandwidth Note 7 Measured for 5 minutes in still air V a e 15V Vb eb 15V Warm-up drift is proportionally reduced at lower supply voltages Fixed Gain and Programmable 1000 500 12 04 02 40 30 1 70 5 5 0 01 100 18 15 02 40 100 0 36 25 15 10 0 005 10 90 10 02 40 200 0 24 20 50 100 0 05 Units nV SHz mVp-p pA SHz pAp-p kHz V ms ms mV mV % Common-Mode Input Voltage Limit Supply Current vs Supply Voltage Input Bias Current vs Temperature Output Swing Referred to Supplies Supply Current vs Temperature Input Offset Current vs Temperature TL H 5609 – 3 4 Typical Performance Characteristics Output Current Limit (Continued) Input Current Noise Input Noise Voltage Input Current vs Voltage Overdrive Gain Non-Linearity Gain Error vs Frequency Trimmed to zero at 100 Hz Gain Error vs Frequency Positive Power Supply Rejection Negative Power Supply Rejection Trimmed to zero at 100 Hz Negative Power Supply Rejection Negative Power Supply Rejection Negative Power Supply Rejection TL H 5609 – 4 5 Typical Performance Characteristics CMRR with Balanced Source Resistance (Continued) CMRR with Balanced Source Resistance CMRR with Balanced Source Resistance CMRR with Unbalanced Source Resistance CMRR with Unbalanced Source Resistance CMRR with Unbalanced Source Resistance CMRR with Balanced Source Resistance CMRR with Balanced Source Resistance CMRR with Balanced Source Resistance CMRR with Unbalanced Source Resistance CMRR with Unbalanced Source Resistance CMRR with Unbalanced Source Resistance TL H 5609 – 5 6 Typical Performance Characteristics (Continued) Shield Driver Bias Voltage Shield Driver Loading Error Shield Driver Loading Error Shield Driver Loading Error Small Signal Transient Response Small Signal Transient Response Small Signal Transient Response Small Signal Transient Response Large Signal Transient Response Large Signal Transient Response Large Signal Transient Response Large Signal Transient Response TL H 5609 – 6 7 Simplified Schematic (pin numbers in parentheses are for 8-pin package) TL H 5609 – 7 Theory of Operation Referring to the Simplified Schematic it can be seen that the input voltage is applied across the bases of Q1 and Q2 and appears between their emitters If RE1-2 is the resistance across these emitters a differential current equal to VIN RE1-2 flows from Q1’s emitter to Q2’s The second stage amplifier shown maintains Q1 and Q2 at equal collector currents by negative feedback to Q4 The emitter currents of Q3 and Q4 must therefore be unbalanced by an amount equal to the current flow across RE1-2 Defining RE3-4 e R5 a R6 the differential voltage across the emitters of Q4 to Q3 is equal to VIN c RE3-4 RE 1-2 This voltage divided by the attenuation factor R2 R4 e R3 a R4 R1 a R2 is equal to the output-to-reference voltage Hence the overall gain is given by VOUT R3 a R4 RE3-4 e c Ge VIN R4 RE1-2 8 Application Hints The LM363 was designed to be as simple to use as possible but several general precautions must be taken The differential inputs are directly coupled and need a return path to power supply common Worst-case bias currents are only 10 nA for the LM363 so the return impedance can be as high as 100 MX Ground drops between signal return and IC supply common should not be ignored While the LM363 has excellent common-mode rejection signals must remain within the proper common-mode range for this specification to apply Operating common-mode range is guaranteed from b10V to a 10V with g15V supplies The high-gain (500 or 1000) versions have large gain-bandwidth products (15 MHz or 30 MHz) so board layout is fairly critical The differential input leads should be kept away from output force and sense leads especially at high impedances Only 1 pF from output to positive input at 100 kX source impedance can cause oscillations The gain adjust leads on the 16-pin package should be treated as inputs and kept away from the output wiring POWER SUPPLY The LM363 may be powered from split supplies from g5V to g18V (or single-ended supplies from 10V to 36V) Positive supply current is