LT1920 Single Resistor Gain Programmable, Precision Instrumentation Amplifier FEATURES DESCRIPTIO U ■ Single Gain Set Resistor: G = 1 to 10,000 The LT ®1920 is a low power, precision instrumentation ■ Gain Error: G = 10, 0.3% Max amplifier that requires only one external resistor to set gains ■ Gain Nonlinearity: G = 10, 30ppm Max of 1 to 10,000. The low voltage noise of 7.5nV/√Hz (at 1kHz) ■ Input Offset Voltage: G = 10, 225µV Max is not compromised by low power dissipation (0.9mA typical ■ Input Offset Voltage Drift: 1µV/°C Max for ±2.3V to ±15V supplies). ■ Input Bias Current: 2nA Max The high accuracy of 30ppm maximum nonlinearity and ■ PSRR at G = 1: 80dB Min 0.3% max gain error (G = 10) is not degraded even for load ■ CMRR at G = 1: 75dB Min resistors as low as 2k (previous monolithic instrumentation ■ Supply Current: 1.3mA Max amps used 10k for their nonlinearity specifications). The ■ ± ± Wide Supply Range: 2.3V to 18V LT1920 is laser trimmed for very low input offset voltage ■ √ 1kHz Voltage Noise: 7.5nV/ Hz (125µV max), drift (1µV/°C), high CMRR (75dB, G = 1) and ■ µ 0.1Hz to 10Hz Noise: 0.28 VP-P PSRR (80dB, G = 1). Low input bias currents of 2nA max are ■ Available in 8-Pin PDIP and SO Packages achieved with the use of superbeta processing. The output ■ Meets IEC 1000-4-2 Level 4 ESD Tests with can handle capacitive loads up to 1000pF in any gain configu- Two External 5k Resistors ration while the inputs are ESD protected up to 13kV (human body). The LT1920 with two external 5k resistors passes the U IEC 1000-4-2 level 4 specification. APPLICATIO S The LT1920, offered in 8-pin PDIP and SO packages, is a pin ■ Bridge Amplifiers for pin and spec for spec improved replacement for the ■ Strain Gauge Amplifiers AD620. The LT1920 is the most cost effective solution for ■ Thermocouple Amplifiers precision instrumentation amplifier applications. For even ■ Differential to Single-Ended Converters better guaranteed performance, see the LT1167. ■ Medical Instrumentation , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO U Single Supply Barometer VS Gain Nonlinearity R5 LUCAS NOVA SENOR 392k VS 3 8 NPC-1220-015-A-3L + 1 2 – 1/2 1 – 7 1 4 1 LT1490 5k LT1634CCZ-1.25 2 5k – R1 2 4 825Ω 6 R6 LT1920 G = 60 1k 2 5k R2 5k 12Ω 8 5 + TO 6 + 3 3 4-DIGIT NONLINEARITY (100ppm/DIV) R4 RSET 4 50k DVM 5 5 R3 + OUTPUT VOLTAGE (2V/DIV) 7 50k 1/2 G = 1000 LT1490 6 RL = 1k – VOUT = ±10V 1167 TA02 R8 R7 VOLTS INCHES Hg 100k 50k 2.800 28.00 VS = 8V TO 30V 3.000 30.00 3.200 32.00 1920 TA01 1 LT1920 WW U W W U ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATIONU (Note 1) ORDER PART ± TOP VIEW Supply Voltage ...................................................... 20V NUMBER Differential Input Voltage (Within the RG 1 8 RG Supply Voltage) ..................................................... ±40V –IN 2 – 7 +VS LT1920CN8 Input Voltage (Equal to Supply Voltage) ................ ±20V +IN 3 + 6 OUTPUT LT1920CS8 Input Current (Note 3) ........................................ ±20mA –VS 4 5 REF LT1920IN8 LT1920IS8 Output Short-Circuit Duration .......................... Indefinite N8 PACKAGE Operating Temperature Range ................ – 40°C to 85°C 8-LEAD PDIP S8 PACKAGE Specified Temperature Range 8-LEAD PLASTIC SO S8 PART MARKING LT1920C (Note 4) .................................... 0°C to 70°C TJMAX = 150°C, θJA = 130°C/ W (N8) ° θ ° 1920 LT1920I .............................................. – 40°C to 85°C TJMAX = 150 C, JA = 190 C/ W (S8) 1920I Storage Temperature Range ................. –65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS VS = ±15V, VCM = 0V, TA = 25°C, RL = 2k, unless otherwise noted. SYMBOL PARAMETER CONDITIONS (Note 6) MIN TYP MAX UNITS G Gain Range G = 1 + (49.4k/RG) 1 10k Gain Error G = 1 0.008 0.1 % G = 10 (Note 2) 0.010 0.3 % G = 100 (Note 2) 0.025 0.3 % G = 1000 (Note 2) 0.040 0.35 % G/T Gain vs Temperature G < 1000 (Note 2) ● 20 50 ppm/°C Gain Nonlinearity (Note 5) VO = ±10V, G = 1 10 ppm VO = ±10V, G = 10 and 100 10 30 ppm VO = ±10V, G = 100 and 1000 20 ppm VOST Total Input Referred Offset Voltage VOST = VOSI + VOSO/G VOSI Input Offset Voltage G = 1000, VS = ±5V to ±15V 30 125 µV G = 1000, VS = ±5V to ±15V ● 185 µV VOSI/T Input Offset Drift (RTI) (Note 3) ● 1 µV/°C VOSO Output Offset Voltage G = 1, VS = ±5V to ±15V 400 1000 µV G = 1, VS = ±5V to ±15V ● 1500 µV VOSO/T Output Offset Drift (Note 3) ● 515µV/°C IOS Input Offset Current 0.3 1 nA IB Input Bias Current 0.5 2 nA en Input Noise Voltage, RTI 0.1Hz to 10Hz, G = 1 2.00 µVP-P 0.1Hz to 10Hz, G = 10 0.50 µVP-P 0.1Hz to 10Hz, G = 100 and 1000 0.28 µVP-P 2 2 Total RTI Noise = √eni + (eno/G) eni Input Noise Voltage Density, RTI fO = 1kHz 7.5 nV/√Hz eno Output Noise Voltage Density, RTI fO = 1kHz 67 nV/√Hz in Input Noise Current fO = 0.1Hz to 10Hz 10 pAP-P Input Noise Current Density fO = 10Hz 124 fA/√Hz RIN Input Resistance VIN = ±10V 200 GΩ CIN(DIFF) Differential Input Capacitance fO = 100kHz 1.6 pF 2 LT1920 ELECTRICAL CHARACTERISTICS VS = ±15V, VCM = 0V, TA = 25°C, RL = 2k, unless otherwise noted. SYMBOL PARAMETER CONDITIONS (Note 6) MIN TYP MAX UNITS CIN(CM) Common Mode Input Capacitance fO = 100kHz 1.6 pF VCM Input Voltage Range G = 1, Other Input Grounded VS = ±2.3V to ±5V –VS + 1.9 +VS – 1.2 V VS = ±5V to ±18V –VS + 1.9 +VS – 1.4 V VS = ±2.3V to ±5V ● –VS + 2.1 +VS – 1.3 V VS = ±5V to ±18V ● –VS + 2.1 +VS – 1.4 V CMRR Common Mode Rejection Ratio 1k Source Imbalance, VCM = 0V to ±10V G = 1 75 95 dB G = 10 95 115 dB G = 100 110 125 dB G = 1000 110 140 dB PSRR Power Supply Rejection Ratio VS = ±2.3 to ±18V G = 1 80 120 dB G = 10 100 135 dB G = 100 120 140 dB G = 1000 120 150 dB IS Supply Current VS = ±2.3V to ±18V 0.9 1.3 mA VOUT Output Voltage Swing RL = 10k VS = ±2.3V to ±5V –VS + 1.1 +VS – 1.2 V VS = ±5V to ±18V –VS + 1.2 +VS – 1.3 V VS = ±2.3V to ±5V ● –VS + 1.4 +VS – 1.3 V VS = ±5V to ±18V ● –VS + 1.6 +VS – 1.5 V IOUT Output Current 20 27 mA BW Bandwidth G = 1 1000 kHz G = 10 800 kHz G = 100 120 kHz G = 1000 12 kHz SR Slew Rate G = 1, VOUT = ±10V 1.2 V/µs Settling Time to 0.01% 10V Step G = 1 to 100 14 µs G = 1000 130 µs RREFIN Reference Input Resistance 20 kΩ IREFIN Reference Input Current VREF = 0V 50 µA VREF Reference Voltage Range – VS + 1.6 +VS – 1.6 V AVREF Reference Gain to Output 1 ± 0.0001 The ● denotes specifications that apply over the full specified Note 5: This parameter is measured in a high speed automatic tester that temperature range. does not measure the thermal effects with longer time constants. The Note 1: Absolute Maximum Ratings are those values beyond which the life magnitude of these thermal effects are dependent on the package used, of a device may be impaired. heat sinking and air flow conditions. Note 2: Does not include the effect of the external gain resistor RG. Note 6: Typical parameters are defined as the 60% of the yield parameter Note 3: This parameter is not 100% tested. distribution. Note 4: The LT1920C is designed, characterized and expected to meet the industrial temperature limits, but is not tested at – 40°C and 85°C. I-grade parts are guaranteed. 3 LT1920 TYPICAL PERFOR A CEUW CHARACTERISTICS Gain Nonlinearity, G = 1 Gain Nonlinearity, G = 10 Gain Nonlinearity, G = 100 NONLINEARITY (1ppm/DIV) NONLINEARITY (10ppm/DIV) NONLINEARITY (10ppm/DIV) 1167 G01 1167 G02 1167 G03 G = 1 OUTPUT VOLTAGE (2V/DIV) G = 10 OUTPUT VOLTAGE (2V/DIV) G = 100 OUTPUT VOLTAGE (2V/DIV) RL = 2k RL = 2k RL = 2k ± VOUT = ±10V VOUT = ±10V VOUT = 10V Gain Nonlinearity, G = 1000 Gain Error vs Temperature Warm-Up Drift 0.20 14 VS = ±15V ° 0.15 TA = 25 C V) 12 µ G = 1 S8 0.10 10 0.05 G = 1 8 0 N8 6 –0.05 VS = ±15V GAIN ERROR (%) G = 10* NONLINEARITY (100ppm/DIV) VOUT = ±10V 4 –0.10 R = 2k L G = 100* 1167 G04 *DOES NOT INCLUDE OUTPUT VOLTAGE (2V/DIV) CHANGE IN OFFSET VOLTAGE ( 2 G = 1000 –0.15 TEMPERATURE EFFECTS G = 1000* RL = 2k ± OF RG VOUT = 10V –0.20 0 –50 –25 0 2550 75 100 0 1234 5 TEMPERATURE (°C) TIME AFTER POWER ON (MINUTES) 1920 G06 1920 G09 Input Bias Current Common Mode Rejection Ratio Negative Power Supply Rejection vs Common Mode Input Voltage vs Frequency Ratio vs Frequency 500 160 160 + VS = ±15V V = 15V 400 G = 1000 ° ° 140 TA = 25 C 140 G = 100 TA = 25 C G = 100 1k SOURCE 300 120 G = 10 IMBALANCE 120 G = 10 200 G = 1000 100 G = 1 G = 1 100 100 0 70°C 85°C 80 80 –100 60 60 ° –200 0 C 25°C 40 40 INPUT BIAS CURRENT (pA) –300 –40°C 20 –400 20 COMMON MODE REJECTION RATIO (dB) –500 0 0 –15 –12–9 –6 –3 0 3 6 9 12 15 0.1 110100 1k10k 100k NEGATIVE POWER SUPPLY REJECTION RATIO (dB) 0.1 110100 1k10k 100k COMMON MODE INPUT VOLTAGE (V) FREQUENCY (Hz) FREQUENCY (Hz) 1920 G13 1920 G14 1920 G15 4 LT1920 TYPICAL PERFOR A CEUW CHARACTERISTICS Positive Power Supply Rejection Ratio vs Frequency Gain vs Frequency Supply Current vs Supply Voltage 160 60 1.50 V – = –15V G = 1000 ° 140 TA = 25 C 50 G = 10 G = 1000 G = 100 120 G = 100 40 1.25 100 G = 1 30 85°C G = 10 25°C 80 20 1.00 60 GAIN (dB) 10 –40°C G = 1 40 0 SUPPLY CURRENT (mA) 0.75 20 –10 VS = ±15V TA = 25°C 0 –20 0.50 POSITIVE POWER SUPPLY REJECTION RATIO (dB) 0.1 110100 1k10k 100k 0.010.1 1 10100 1000 0 5 10 15 20 FREQUENCY (Hz) FREQUENCY (kHz) SUPPLY VOLTAGE (±V) 1920 G17 1920 G16 1920 G18 Voltage Noise Density 0.1Hz to 10Hz Noise Voltage, 0.1Hz to 10Hz Noise Voltage, RTI vs Frequency G = 1 G = 1000 1000 ± VS = ±15V VS = ±15V VS = 15V ° TA = 25°C TA = 25°C TA = 25 C Hz) √ 1/fCORNER = 10Hz V/DIV) 100 V/DIV) GAIN = 1 µ µ 1/fCORNER = 9Hz GAIN = 10 1/f = 7Hz 10 CORNER GAIN