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LT1490A/LT1491A Dual/Quad Over-The-Top Micropower Rail-to-Rail Input and Output Op Amps FEATURES s s s s s s DESCRIPTIO s s s s s s s s s Low Input Offset Voltage: 500V Max Output Swings to 10mV Max from V - Rail-to-Rail Input and Output Micropower: 50A/Amplifier Max MSOP Package Over-The-TopTM Input Common Mode Range Extends 44V Above V -, Independent of V + Specified on 3V, 5V and 15V Supplies High Output Current: 20mA Output Drives 10,000pF with Output Compensation Reverse Battery Protection to 18V No Supply Sequencing Problems High Voltage Gain: 1500V/mV High CMRR: 98dB No Phase Reversal Gain Bandwidth Product: 200kHz APPLICATIO S s s s s s Battery- or Solar-Powered Systems Portable Instrumentation Sensor Conditioning Supply Current Sensing Battery Monitoring Micropower Active Filters 4mA to 20mA Transmitters , LTC and LT are registered trademarks of Linear Technology Corporation. Over-The-Top is a trademark of Linear Technology Corporation. The LT (R)1490A/LT1491A are enhanced versions of the popular LT1490/LT1491 dual and quad op amps with improved input offset voltage (500V max) and output voltage swing (10mV max from V -). They are recommended as replacements for the LT1490/LT1491 in all new designs. The LT1490A/LT1491A operate on all single and split supplies with a total voltage of 2V to 44V, drawing only 40A of quiescent current per amplifier. These amplifiers are reverse supply protected; they draw virtually no current for reverse supply up to 18V. The input range of the LT1490A/LT1491A includes both supplies and the output swings to both supplies. Unlike most micropower op amps, the LT1490A/ LT1491A can drive heavy loads; their rail-to-rail outputs drive 20mA. The LT1490A/LT1491A are unity-gain stable and drive all capacitive loads up to 10,000pF when optional 0.22F and 150 compensation is used. The LT1490A/LT1491A have a unique input stage that operates and remains high impedance when above the positive supply. The inputs take 44V both differential and common mode even when operating on a 3V supply. Built-in resistors protect the inputs for faults below the negative supply up to 15V. There is no phase reversal of the output for inputs 15V below V - or 44V above V -, independent of V +. The LT1490A dual op amp is available in the 8-pin MSOP, PDIP and SO packages. The quad LT1491A is available in the 14-pin SO and PDIP packages. TYPICAL APPLICATIO CHARGER VOLTAGE Battery Monitor RS 0.2 IBATT RA 2k RA 2k + 1/4 LT1491A Q1 2N3904 - 1/4 LT1491A LOGIC - Q2 2N3904 + RB 2k RB 2k LOAD + 1/4 LT1491A LOGIC HIGH (5V) = CHARGING LOGIC LOW (0V) = DISCHARGING - RG 10k S1 10k + 1/4 LT1491A VOUT + VBATT = 12V - 90.9k 1490A TA01 VOUT V IBATT = = OUT AMPS (RS)(RG /RA)(GAIN) GAIN S1 = OPEN, GAIN = 1 S1 = CLOSED, GAIN = 10 RA = RB VS = 5V, 0V U U U 1 LT1490A/LT1491A ABSOLUTE AXI U RATI GS Total Supply Voltage (V + to V -) ............................. 44V Differential Input Voltage ........................................ 44V Input Current ..................................................... 12mA Output Short-Circuit Duration (Note 2) ........ Continuous Operating Temperature Range (Note 3) LT1490AC/LT1491AC ......................... - 40C to 85C LT1490AI/LT1491AI ........................... - 40C to 85C LT1490AH/LT1491AH ...................... - 40C to 125C PACKAGE/ORDER I FOR ATIO TOP VIEW OUT A -IN A +IN A V- 1 2 3 4 8 V+ 7 OUT B 6 -IN B 5 +IN B OUT A -IN A +IN A V- 1 2 A 3 B 4 MS8 PACKAGE 8-LEAD PLASTIC MSOP TJMAX = 150C, JA = 250C/ W N8 PACKAGE 8-LEAD PDIP TJMAX = 150C, JA = 130C/ W (N8) TJMAX = 150C, JA = 190C/ W (S8) ORDER PART NUMBER LT1490ACMS8 LT1490AIMS8 LT1490AHMS8 MS8 PART MARKING LTNG LTPU LTRK ORDER PART NUMBER LT1490ACN8 LT1490ACS8 LT1490AIN8 LT1490AIS8 LT1490AHS8 Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS The q denotes specifications which apply over the full operating temperature range of - 40C TA 85C, otherwise specifications are at TA = 25C. VS = 3V, 0V; VS = 5V, 0V; VCM = VOUT = half supply unless otherwise noted. (Note 4) LT1490AC/LT1491AC LT1490AI/LT1491AI MIN TYP MAX 110 q q SYMBOL VOS PARAMETER Input Offset Voltage (Note 5) CONDITIONS LT1490A N, S Packages 0C TA 70C - 40C TA 85C LT1490A MS8 Package, LT1491A N, S Packages q 0C TA 70C - 40C TA 85C q Input Offset Voltage Drift (Note 9) - 40C TA 85C q 2 U U W WW U W (Note 1) Specified Temperature Range (Note 4) LT1490AC/LT1490AI .......................... - 40C to 85C LT1491AC/LT1491AI .......................... - 40C to 85C LT1490AH/LT1491AH ...................... - 40C to 125C Junction Temperature .......................................... 150C Storage Temperature Range ................ - 65C to 150C Lead Temperature (Soldering, 10 sec)................. 300C TOP VIEW TOP VIEW 8 7 6 5 V + OUT A 1 -IN A 2 +IN A 3 V+ 4 +IN B 5 -IN B 6 OUT B 7 N PACKAGE 14-LEAD PDIP B C A D 14 OUT D 13 -IN D 12 +IN D 11 V - 10 +IN C 9 8 -IN C OUT C OUT B -IN B +IN B S8 PACKAGE 8-LEAD PLASTIC SO S PACKAGE 14-LEAD PLASTIC SO TJMAX = 150C, JA = 110C/ W (N) TJMAX = 150C, JA = 150C/ W (S) S8 PART MARKING 1490A 1490AI 1490AH ORDER PART NUMBER LT1491ACN LT1491ACS LT1491AIN LT1491AIS LT1491AHS UNITS V V V V V V V/C 500 700 800 1000 1200 1400 4 220 2 LT1490A/LT1491A ELECTRICAL CHARACTERISTICS The q denotes specifications which apply over the full operating temperature range of - 40C TA 85C, otherwise specifications are at TA = 25C. VS = 3V, 0V; VS = 5V, 0V; VCM = VOUT = half supply unless otherwise noted. (Note 4) LT1490AC/LT1491AC LT1490AI/LT1491AI MIN TYP MAX q q q q q SYMBOL IOS IB PARAMETER Input Offset Current CONDITIONS VCM = 44V (Note 6) UNITS nA A nA A nA pA/C VP-P nV/Hz pA/Hz M M pF 0.2 1 3 0.3 2 1 50 0.015 6 4 17 11 4.6 0.8 0.8 8 10 Input Bias Current VCM = 44V (Note 6) VS = 0V Input Bias Current Drift Input Noise Voltage - 40C TA 85C 0.1Hz to 10Hz f = 1kHz f = 1kHz Differential Common Mode, VCM = 0V to 44V en in RIN CIN CMRR AVOL Input Noise Voltage Density Input Noise Current Density Input Resistance Input Capacitance Input Voltage Range Common Mode Rejection Ratio (Note 6) Large-Signal Voltage Gain q 0 84 80 200 133 100 400 250 200 98 98 1500 44 V dB dB V/mV V/mV V/mV V/mV V/mV V/mV VCM = 0V to VCC - 1V VCM = 0V to 44V VS = 3V, VO = 500mV to 2.5V, RL = 10k 0C TA 70C - 40C TA 85C VS = 5V, VO = 500mV to 4.5V, RL = 10k 0C TA 70C - 40C TA 85C q q q q q q q q q q q q q q 1500 VOL Output Voltage Swing Low VS = 3V, No Load VS = 3V, ISINK = 5mA VS = 5V, No Load VS = 5V, ISINK = 5mA VS = 5V, ISINK = 10mA 3 250 3 250 330 2.95 2.55 4.95 4.30 10 10 15 15 2.978 2.6 4.978 4.6 15 30 25 30 98 2 18 27 40 10 450 10 500 500 mV mV mV mV mV V V V V mA mA mA mA dB VOH Output Voltage Swing High VS = 3V, No Load VS = 3V, ISOURCE = 5mA VS = 5V, No Load VS = 5V, ISOURCE = 10mA ISC Short-Circuit Current (Note 2) VS = 3V, Short to GND VS = 3V, Short to VCC VS = 5V, Short to GND VS = 5V, Short to VCC PSRR Power Supply Rejection Ratio Minimum Operating Supply Voltage Reverse Supply Voltage VS = 2.5V to 12.5V, VCM = VO = 1V IS = - 100A per Amplifier q q q q 84 2.5 50 55 V V A A kHz kHz kHz V/s V/s V/s IS GBW Supply Current per Amplifier (Note 7) Gain Bandwidth Product (Note 6) Slew Rate (Note 8) f = 1kHz 0C TA 70C - 40C TA 85C AV = - 1, RL = 0C TA 70C - 40C TA 85C q q q q 110 100 90 0.035 0.031 0.030 180 SR 0.06 3 LT1490A/LT1491A ELECTRICAL CHARACTERISTICS SYMBOL VOS PARAMETER Input Offset Voltage (Note 5) The q denotes specifications which apply over the full operating temperature range of - 40C TA 85C, otherwise specifications are at TA = 25C. VS = 15V; VCM = 0V, VOUT = 0V unless otherwise noted. (Note 4) LT1490AC/LT1491AC LT1490AI/LT1491AI MIN TYP MAX 150 q q CONDITIONS LT1490A N, S Packages 0C TA 70C - 40C TA 85C UNITS V V V V V V V/C nA nA pA/C VP-P nV/Hz pA/Hz M M pF 700 950 1100 1200 1350 1500 6 0.8 8 LT1490A MS8 Package, LT1491A N, S Packages 0C TA 70C q q - 40C TA 85C Input Offset Voltage Drift (Note 9) IOS IB Input Offset Current Input Bias Current Input Bias Current Drift Input Noise Voltage en in RIN CIN CMRR AVOL Input Noise Voltage Density Input Noise Current Density Input Resistance Input Capacitance Input Voltage Range Common Mode Rejection Ratio Large-Signal Voltage Gain VCM = - 15V to 29V VO = 14V, RL = 10k 0C TA 70C - 40C TA 85C No Load IOUT = 5mA IOUT = 10mA Short to GND 0C TA 70C - 40C TA 85C VS = 1.25V to 22V q q q q q q 250 - 40C TA 85C q q q 2 0.2 1 5 1 50 0.015 6 17 15000 4.6 - 15 80 100 75 50 14.9 14.5 14.5 20 15 10 88 98 250 - 40C TA 85C 0.1Hz to 10Hz f = 1kHz f = 1kHz Differential Common Mode, VCM = - 15V to 14V q 29 V dB V/mV V/mV V/mV V V V mA mA mA dB VO Output Voltage Swing 14.978 14.750 14.670 25 ISC Short-Circuit Current (Note 2) q q q q PSRR IS GBW Power Supply Rejection Ratio Supply Current per Amplifier Gain Bandwidth Product 98 50 70 85 A A kHz kHz kHz V/s V/s V/s f = 1kHz 0C TA 70C - 40C TA 85C AV = - 1, RL = , VO = 10V, Measure at VO = 5V 0C TA 70C - 40C TA 85C q q 125 110 100 0.0375 200 SR Slew Rate 0.07 q q 0.0330 0.0300 4 LT1490A/LT1491A ELECTRICAL CHARACTERISTICS SYMBOL VOS PARAMETER Input Offset Voltage (Note 5) The q denotes specifications which apply over the full operating temperature range of - 40C TA 125C. VS = 3V, 0V; VS = 5V, 0V; VCM = VOUT = half supply unless otherwise noted. (Note 4) CONDITIONS LT1490AHS8 q LT1490AH/LT1491AH MIN TYP MAX 110 220 q q UNITS V V V V V/C nA A nA A V dB dB 500 2500 1000 3000 6 2 1.5 20 15 LT1490AHMS8, LT1491AHS Input Offset Voltage Drift (Note 9) IOS IB Input Offset Current VCM = 44V (Note 6) Input Bias Current VCM = 44V (Note 6) Input Voltage Range CMRR AVOL Common Mode Rejection Ratio (Note 6) Large-Signal Voltage Gain VCM = 0.3V to VCC -1V VCM = 0.3V to 44V VS = 3V, VO = 500mV to 2.5V, RL = 10k q 3 q q q q q q q 0.3 60 74 200 25 400 50 1500 1500 44 V/mV V/MV V/mV V/mV 15 450 15 500 mV mV mV mV V V V V dB 2.5 V V A A kHz kHz V/s V/s VS = 5V, VO = 500mV to 4.5V, RL = 10k q VOL Output Voltage Swing Low VS = 3V, No Load VS = 3V, ISINK = 2.5mA VS = 5V, No Load VS = 5V, ISINK = 2.5mA q q q q q q q q q q VOH Output Voltage Swing High VS = 3V, No Load VS = 3V, ISOURCE = 5mA VS = 5V, No Load VS = 5V, ISOURCE = 10mA 2.925 2.350 4.925 4.100 80 18 40 50 70 PSRR Power Supply Rejection Ratio Minimum Operating Supply Voltage Reverse Supply Voltage VS = 2.5V to 12.5V, VCM = VO = 1V IS = - 100A per Amplifier q q IS GBW SR Supply Current per Amplifier (Note 7) Gain Bandwidth Product (Note 6) Slew Rate (Note 8) f = 1kHz q 110 60 0.035 0.015 180 0.06 AV = - 1, RL = q 5 LT1490A/LT1491A ELECTRICAL CHARACTERISTICS SYMBOL VOS PARAMETER Input Offset Voltage (Note 5) The q denotes specifications which apply over the full operating temperature range of - 40C TA 125C. VS = 15V, VCM = 0V, VOUT = 0V unless otherwise noted. (Note 4) CONDITIONS LT1490AHS8 q LT1490AH/LT1491AH MIN TYP MAX 150 250 q q q q q UNITS V V V V V/C nA nA V dB V/mV V/mV mV mV dB 700 2700 1200 3200 7 2 20 LT1490AHMS8, LT1491AHS Input Offset Voltage Drift (Note 9) IOS IB CMRR AVOL VO PSRR IS GBW SR Input Offset Current Input Bias Current Input Voltage Range Common Mode Rejection Ratio Large-Signal Voltage Gain Output Voltage Swing Power Supply Rejection Ratio Supply Current per Amplifier q 3 -14.7 72 100 4 14.8 14.3 84 50 250 29 VCM = -14.7V to 29V VO = 14V, RL = 10k q q No Load IOUT = 2.5mA VS = 1.25V to 22V q q q 70 95 A A kHz kHz V/s V/s Gain Bandwidth Product Slew Rate f = 1kHz q 125 75 0.0375 0.02 200 0.07 AV = - 1, RL = q Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: A heat sink may be required to keep the junction temperature below absolute maximum. This depends on the power supply voltage and how many amplifiers are shorted. Note 3: The LT1490AC/LT1491AC and LT1490AI/LT1491AI are guaranteed functional over the operating temperature range of - 40C to 85C. The LT1490AH/LT1491AH are guaranteed functional over the operating temperature range of - 40C to 125C. Note 4: The LT1490AC/LT1491AC are guaranteed to meet specified performance from 0C to 70C. The LT1490AC/LT1491AC are designed, characterized and expected to meet specified performance from - 40C to 85C but are not tested or QA sampled at these temperatures. The LT1490AI/LT1491AI are guaranteed to meet specified performance from -40C to 85C. The LT1490AH/LT1491AH are guaranteed to meet specified performance from - 40C to 125C. Note 5: ESD (Electrostatic Discharge) sensitive device. Extensive use of ESD protection devices are used internal to the LT1490A/LT1491A. However, high electrostatic discharge can damage or degrade the device. Use proper ESD handling precautions. Note 6: VS = 5V limits are guaranteed by correlation to VS = 3V and VS = 15V tests. Note 7: VS = 3V limits are guaranteed by correlation to VS = 5V and VS = 15V tests. Note 8: Guaranteed by correlation to slew rate at VS = 15V and GBW at VS = 3V and VS = 15V tests. Note 9: This parameter is not 100% tested. 6 LT1490A/LT1491A TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage 80 70 60 50 40 30 20 10 0 0 5 10 15 20 25 30 35 40 TOTAL SUPPLY VOLTAGE (V) 45 TA = 125C TA = 25C CHANGE IN INPUT OFFSET VOLTAGE (V) SUPPLY CURRENT PER AMPLIFIER (A) INPUT BIAS CURRENT (nA) TA = -55C Output Saturation Voltage vs Load Current (Output High) 1 VS = 5V, 0V 1 OUTPUT SATURATION VOLTAGE (mV) OUTPUT SATURATION VOLTAGE (V) OUTPUT SATURATION VOLTAGE (V) TA = 125C 100m TA = 25C TA = -55C 10m 1 10 1m 10m 100 SOURCING LOAD CURRENT (A) 0.1Hz to 10Hz Noise Voltage INPUT NOISE VOLTAGE DENSITY (nV/Hz) INPUT NOISE CURRENT DENSITY (pA/Hz) VS = 2.5V NOISE VOLTAGE (400nV/DIV) 0 1 2 3 456 TIME (SEC) 7 UW 1490A G01 1490A G04 Minimum Supply Voltage 400 300 200 100 0 -100 -200 -300 TA = 125C 0 1 3 4 2 TOTAL SUPPLY VOLTAGE (V) 5 1490A G02 Input Bias Current vs Common Mode Voltage 5000 VS = 5V, 0V 3000 1000 TA = -55C 30 20 10 0 -10 -0.4 0 4.0 4.4 4.8 5.2 5.6 COMMON MODE VOLTAGE (V) 44 TA = 125C TA = 25C TA = 25C TA = -55C - 400 1490A G03 Output Saturation Voltage vs Load Current (Output Low) VS = 5V, 0V Output Saturation Voltage vs Input Overdrive 100 VS = 5V, 0V 90 NO LOAD 80 70 60 50 40 30 20 10 0 0 10 OUTPUT LOW 30 40 20 INPUT OVERDRIVE (mV) 50 1490A G06 100m TA = 125C TA = 25C 10m TA = -55C OUTPUT HIGH 100m 1m 0.1 1 10 100 1m 10m SINKING LOAD CURRENT (A) 100m 1490A G05 Noise Voltage Density vs Frequency 120 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0 Input Noise Current vs Frequency 100 80 60 40 8 9 10 20 1 10 100 FREQUENCY (Hz) 1k 1490A G08 1 10 100 FREQUENCY (Hz) 1k 1490A G09 1490A G07 7 LT1490A/LT1491A TYPICAL PERFOR A CE CHARACTERISTICS Gain and Phase Shift vs Frequency 70 60 50 40 PHASE VS = 2.5V 100 GAIN BANDWIDTH PRODUCT (kHz) GAIN (dB) 30 20 10 0 -10 -20 -30 1 10 100 FREQUENCY (kHz) GAIN 20 0 -20 - 40 - 60 - 80 -100 1000 1490A G10 200 180 VS = 1.5V 160 140 120 100 -50 -25 VS = 15V SLEW RATE (V/s) Gain Bandwidth Product and Phase Margin vs Supply Voltage 250 GAIN BANDWIDTH PRODUCT (kHz) COMMON MODE REJECTION RATIO (dB) 240 230 220 210 200 190 180 170 160 150 0 5 10 15 20 25 30 35 40 TOTAL SUPPLY VOLTAGE (V) 45 RL = 10k f = 1kHz 10 20 GAIN BANDWIDTH 30 40 PHASE MARGIN 50 PHASE MARGIN (DEG) POWER SUPPLY REJECTION RATIO (dB) Gain Bandwidth Product and Phase Margin vs Load Resistance 350 GAIN BANDWIDTH PRODUCT (kHz) CHANNEL SEPARATION (dB) 300 250 200 PHASE MARGIN OUTPUT IMPEDANCE () VS = 2.5V AV = -1 RF = RG = 100k f = 1kHz GAIN BANDWIDTH 150 100 50 1 10 LOAD RESISTANCE (k) 40 30 20 100 1490A G16 8 UW 1490A G13 Gain Bandwidth Product vs Temperature 260 f = 1kHz 240 220 0.10 0.12 80 60 40 Slew Rate vs Temperature RISING, VS = 15V PHASE SHIFT (DEG) 0.08 RISING, VS = 1.5V FALLING, VS = 15V FALLING, VS = 1.5V 0.06 50 25 0 75 TEMPERATURE (C) 100 125 0.04 -50 -25 50 25 0 75 TEMPERATURE (C) 100 125 1490A G11 1490A G12 CMRR vs Frequency 60 120 80 70 60 PSRR vs Frequency VS = 2.5V 100 VS = 15V VS = 1.5V POSITIVE SUPPLY 50 40 30 20 10 0 -10 -20 1 10 FREQUENCY (kHz) 100 1490A G15 80 60 NEGATIVE SUPPLY 40 20 1 10 FREQUENCY (kHz) 100 1490A G14 Channel Separation vs Frequency 80 70 Output Impedance vs Frequency 10k VS = 2.5V 130 120 110 100 90 80 70 60 50 40 0.1 1 10 FREQUENCY (kHz) VS = 15V 1k AV = 100 100 AV = 10 10 AV = 1 PHASE MARGIN (DEG) 60 50 1 100 1490A G17 0.1 0.1 1 10 FREQUENCY (kHz) 100 1490A G18 LT1490A/LT1491A TYPICAL PERFOR A CE CHARACTERISTICS Undistorted Output Swing vs Frequency 35 30 OUTPUT SWING (VP-P) VS = 15V DISTORTION 1% OUTPUT STEP (V) 20 15 10 5 0 0.1 VS = 5V, 0V 2 0 -2 -4 -6 -8 -10 AV = 1 0 20 40 60 80 100 120 140 160 SETTLING TIME (s) 1490A F20 OVERSHOOT (%) 25 1 10 FREQUENCY (kHz) Total Harmonic Distortion + Noise vs Frequency 10 VS = 3V, 0V VOUT = 2VP-P VCM = 1.2V RL = 50k 10 1 THD + NOISE (%) THD + NOISE (%) THD + NOISE (%) 0.1 0.01 AV = -1 AV = 1 0.001 0.01 1 0.1 FREQUENCY (kHz) Open-Loop Gain CHANGE IN INPUT OFFSET VOLTAGE (100V/DIV) VS = 15V RL = 2k RL = 10k RL = 50k -10V 0V 10V OUTPUT VOLTAGE (5V/DIV) UW 1490A G19 1490A G22 1490A G25 Settling Time to 0.1% vs Output Step 10 8 6 4 VS = 15V AV = -1 AV = 1 100 90 80 70 60 50 40 30 20 10 0 Capacitive Load Handling, Overshoot vs Capacitive Load VS = 5V, 0V ISOURCE = 170A AV = 1 AV = 2 AV = 10 AV = 5 AV = -1 100 10 100 1000 CAPACITIVE LOAD (pF) 10000 1490A G21 Total Harmonic Distortion + Noise vs Load Resistance VS = 3V TOTAL AV = 1 VIN = 2VP-P AT 1kHz VS = 1.5V VIN = 1V VS = 3V, 0V VIN = 0.5V TO 2.5V 0.01 VS = 3V, 0V VIN = 0.2V TO 2.2V Total Harmonic Distortion + Noise vs Output Voltage 10 RL = 10k VCM = HALF SUPPLY f = 1kHz 1 AV = -1 VS = 1.5V AV = 1 VS = 1.5V 1 0.1 0.1 0.01 AV = 1 VS = 3V, 0V 0.001 10 1 LOAD RESISTANCE TO GROUND (k) 100 AV = -1 VS = 3V, 0V 10 0.001 0.1 0 1 2 OUTPUT VOLTAGE (VP-P) 3 1490A G24 1490A G23 Large-Signal Response Small-Signal Response VS = 15V AV = -1 1490A G26 VS = 15V AV = 1 1490A G27 9 LT1490A/LT1491A APPLICATIO S I FOR ATIO Supply Voltage The positive supply pin of the LT1490A/LT1491A should be bypassed with a small capacitor (about 0.01F) within an inch of the pin. When driving heavy loads an additional 4.7F electrolytic capacitor should be used. When using split supplies, the same is true for the negative supply pin. The LT1490A/LT1491A are protected against reverse battery voltages up to 18V. In the event a reverse battery condition occurs, the supply current is less than 1nA. The LT1490A/LT1491A can be shut down by removing V +. In this condition the input bias current is typically less than 0.5nA, even if the inputs are 44V above the negative supply. When operating the LT1490A/LT1491A on total supplies of 20V or more, the supply must not rise to its final voltage in less than 1s. This is especially true if low ESR bypass capacitors are used. A series RLC circuit is formed from the supply lead inductance and the bypass capacitor. A resistance of 7.5 in the supply or in the bypass capacitor will dampen the tuned circuit enough to limit the rise time. Inputs The LT1490A/LT1491A have two input stages, NPN and PNP (see the Simplified Schematic), resulting in three distinct operating regions as shown in the Input Bias Current vs Common Mode typical performance curve. For input voltages about 0.8V or more below V +, the PNP input stage is active and the input bias current is typically - 1nA. When the input voltage is about 0.5V or less from V +, the NPN input stage is operating and the input bias current is typically 25nA. Increases in temperature will cause the voltage at which operation switches from the PNP stage to the NPN stage to move towards V +. The input offset voltage of the NPN stage is untrimmed and is typically 600V. A Schottky diode in the collector of each NPN transistor of the NPN input stage allows the LT1490A/LT1491A to operate with either or both of their inputs above V +. At about 0.3V above V + the NPN input transistor is fully saturated and the input bias current is typically 3A at room temperature. The input offset voltage is typically 700V when 10 U operating above V +. The LT1490A/LT1491A will operate with their inputs 44V above V - regardless of V +. The inputs are protected against excursions as much as 15V below V - by an internal 1k resistor in series with each input and a diode from the input to the negative supply. There is no output phase reversal for inputs up to 15V below V -. There are no clamping diodes between the inputs and the maximum differential input voltage is 44V. Output The output voltage swing of the LT1490A/LT1491A is affected by input overdrive as shown in the typical performance curves. The output of the LT1490A/LT1491A can be pulled up to 18V beyond V + with less than 1nA of leakage current, provided that V + is less than 0.5V. The normally reverse-biased substrate diode from the output to V - will cause unlimited currents to flow when the output is forced below V -. If the current is transient and limited to 100mA, no damage will occur. The LT1490A/LT1491A are internally compensated to drive at least 200pF of capacitance under any output loading conditions. A 0.22F capacitor in series with a 150 resistor between the output and ground will compensate these amplifiers for larger capacitive loads, up to 10,000pF, at all output currents. Distortion There are two main contributors of distortion in op amps: output crossover distortion as the output transitions from sourcing to sinking current and distortion caused by nonlinear common mode rejection. Of course, if the op amp is operating inverting there is no common mode induced distortion. When the LT1490A/LT1491A switch between input stages there is significant nonlinearity in the CMRR. Lower load resistance increases the output crossover distortion, but has no effect on the input stage transition distortion. For lowest distortion the LT1490A/ LT1491A should be operated single supply, with the output always sourcing current and with the input voltage swing between ground and (V + - 0.8V). See the Typical Performance Characteristics curves. W UU LT1490A/LT1491A APPLICATIO S I FOR ATIO Gain The open-loop gain is almost independent of load when the output is sourcing current. This optimizes performance TYPICAL APPLICATIO S Square Wave Oscillator 5V 100k 59k + 100k 1/2 LT1490A VOUT - R 50k C 0.1F 1490A TA02 f= 1 2RC VOUT = 5VP-P WITH 5V SUPPLY IS = 200A AT VS = 5V, R = 50k, C = 1nF OUTPUT IS 5kHz SLEW LIMITED TRIANGLE WAVE SI PLIFIED SCHE ATIC V+ Q1 D1 R1 30k Q4 - IN Q17 Q20 OUT Q16 Q15 Q9 Q10 Q13 Q14 Q21 Q18 R3 1k 2A +IN Q7 Q8 Q11 Q12 R2 1k D2 Q2 D3 Q3 Q22 + Q5 Q6 D4 D5 ONE AMPLIFIER U in single supply applications where the load is returned to ground. The typical performance photo of Open-Loop Gain for various loads shows the details. Optional Output Compensation for Capacitive Loads Greater Than 200pF VIN W U W UU + 1/2 LT1490A - CL 10,000pF 0.22F 150 1490A TA04 W Q19 R4 40k R5 40k V- 1490A SS 11 LT1490A/LT1491A PACKAGE DESCRIPTIO 0.007 (0.18) 0.021 0.006 (0.53 0.015) * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE 0.300 - 0.325 (7.620 - 8.255) 0.009 - 0.015 (0.229 - 0.381) ( +0.035 0.325 -0.015 8.255 +0.889 -0.381 ) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 12 U Dimensions in inches (millimeters) unless otherwise noted. MS8 Package 8-Lead Plastic MSOP (LTC DWG # 05-08-1660) 0.118 0.004* (3.00 0.102) 8 76 5 0.193 0.006 (4.90 0.15) 0.118 0.004** (3.00 0.102) 1 0.040 0.006 (1.02 0.15) 0 - 6 TYP SEATING PLANE 0.012 (0.30) 0.0256 REF (0.65) BSC 23 4 0.034 0.004 (0.86 0.102) 0.006 0.004 (0.15 0.102) MSOP (MS8) 1098 N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.400* (10.160) MAX 8 7 6 5 0.255 0.015* (6.477 0.381) 1 2 3 4 0.130 0.005 (3.302 0.127) 0.045 - 0.065 (1.143 - 1.651) 0.065 (1.651) TYP 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 0.003 (0.457 0.076) N8 1098 0.100 (2.54) BSC LT1490A/LT1491A PACKAGE DESCRIPTIO 0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 0.254) 0- 8 TYP 0.014 - 0.019 (0.355 - 0.483) TYP *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 0.016 - 0.050 (0.406 - 1.270) U Dimensions in inches (millimeters) unless otherwise noted. 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 0.228 - 0.244 (5.791 - 6.197) 0.150 - 0.157** (3.810 - 3.988) 1 2 3 4 0.053 - 0.069 (1.346 - 1.752) 0.004 - 0.010 (0.101 - 0.254) 0.050 (1.270) BSC SO8 1298 13 LT1490A/LT1491A PACKAGE DESCRIPTIO 0.300 - 0.325 (7.620 - 8.255) 0.009 - 0.015 (0.229 - 0.381) 0.005 (0.125) MIN 0.100 (2.54) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. BSC MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) +0.035 0.325 -0.015 +0.889 8.255 -0.381 ( ) 14 U Dimensions in inches (millimeters) unless otherwise noted. N Package 14-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.770* (19.558) MAX 14 13 12 11 10 9 8 0.255 0.015* (6.477 0.381) 1 0.130 0.005 (3.302 0.127) 0.020 (0.508) MIN 2 3 4 5 6 7 0.045 - 0.065 (1.143 - 1.651) 0.065 (1.651) TYP 0.125 (3.175) MIN 0.018 0.003 (0.457 0.076) N14 1098 LT1490A/LT1491A PACKAGE DESCRIPTIO 0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 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 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. U Dimensions in inches (millimeters) unless otherwise noted. S Package 14-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.337 - 0.344* (8.560 - 8.738) 14 13 12 11 10 9 8 0.228 - 0.244 (5.791 - 6.197) 0.150 - 0.157** (3.810 - 3.988) 1 2 3 4 5 6 7 0.053 - 0.069 (1.346 - 1.752) 0.004 - 0.010 (0.101 - 0.254) 0.014 - 0.019 (0.355 - 0.483) TYP 0.050 (1.270) BSC S14 1298 15 LT1490A/LT1491A TYPICAL APPLICATIO R2 47k R3 10k C2 0.47F 3 R5 100k 5 + 1/4 LT1491A 7 + 1 D1 1N4148 R1 1/4 LT1491A 33k 2 6 - - C1 1F R4 1.6M R8 620k 20Hz OSCILLATOR CADENCE OSCILLATOR *LED OF OPTO1 ILLUMINATES WHEN THE PHONE IS OFF THE HOOK SEE DESIGN NOTE DN134 FOR A DISCUSSION OF THE CIRCUIT RELATED PARTS PART NUMBER LT1366/LT1367 LT1636 LT1638/LT1639 LT1782 LT1783 DESCRIPTION Dual/Quad Precision, Rail-to-Rail Input and Output Op Amps Single Over-The-Top Micropower Rail-to-Rail Input and Output Op Amp Dual/Quad 1.2MHz Over-The-Top Micropower, Rail-to-Rail Input and Output Op Amps Micropower, Over-The-Top, SOT-23, Rail-to-Rail Input and Output Op Amp 1.2MHz, Over-The-Top, Micropower, Rail-to-Rail Input and Output Op Amp COMMENTS 475V VOS(MAX), 500V/mV AVOL(MIN), 400kHz GBW 55A Supply Current, VCM Extends 44V above VEE, Independent of VCC, MSOP Package, Shutdown Function 0.4V/s Slew Rate, 230A Supply Current per Amplifier SOT-23, 800V VOS(MAX), IS =55A (Max), Gain-Bandwidth = 200kHz, Shutdown Pin SOT-23, 800V VOS(MAX), IS =300A (Max), Gain-Bandwidth = 1.2MHz, Shutdown Pin 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408)432-1900 q FAX: (408) 434-0507 q www.linear-tech.com U Ring-Tone Generator 60V R16 100k Q1 IRF628 C3 0.047F R9 300k R11 10k 10 Z1 15V 100k 8 13 4 14 C7 47F R18 100 R23 4.7k R25 4.7k R26 2k OPTO1* Q5 2N3904 R6 10k Q3 2N3904 R17 620 + 1/4 LT1491A R7 16k C4 0.068F 9 - 12 R14 10k R15 47k - + 1/4 LT1491A R24 11 420 R10 620k R12 SMOOTHING FILTER 10k C5 0.01F R13 130k Z2 15V Q2 IRF9620 POWER AMPLIFIER -180V R20 100k R19 620 UP TO LOAD TEN PHONES Q4 2N3906 R21 150 C6 0.033F 1490A TA03 14901af LT/TP 0600 4K * PRINTED IN USA (c) LINEAR TECHNOLOGY CORPORATION 2000 |
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