LT1490/LT1491 Dual and Quad Micropower Rail-to-Rail Input and Output Op Amps U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Rail-to-Rail Input and Output Single Supply Input Range: – 0.4V to 44V µA/Amplifier Max Micropower: 50µ MSOP Package 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 U APPLICATIO 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. The dual LT ®1490 and quad LT1491 op amps operate on all single and split supplies with a total voltage of 2V to 44V drawing only 40µA of quiescent current per amplifier. These amplifiers are reverse supply protected; they draw no current for reverse supply up to 18V. The input range of the LT1490/ LT1491 includes both supplies and the output swings to both supplies. Unlike most micropower op amps, the LT1490/ LT1491 can drive heavy loads; their rail-to-rail outputs drive 20mA. The LT1490/LT1491 are unity-gain stable and drive all capacitive loads up to 10,000pF when optional 0.22µF and 150Ω compensation is used. The LT1490/LT1491 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 22V. There is no phase reversal of the output for inputs 22V below V – or 44V above V –, independent of V +. The LT1490 dual op amp is available in the 8-pin MSOP, SO and PDIP packages. The quad LT1491 is available in the 14-pin SO and PDIP packages. For new designs it is recommended that the LT1490A/ LT1491A be used instead of the LT1490/LT1491. See the LT1490A/LT1491A data sheet for details. U TYPICAL APPLICATIO Battery Monitor RS 0.2Ω CHARGER VOLTAGE RA 2k RA' 2k IBATT + A 1/4 LT1491 Q1 2N3904 – C 1/4 LT1491 – LOGIC + RB 2k RB' 2k LOAD + Q2 2N3904 – + + RG 10k VBATT = 12V S1 IBATT = LOGIC HIGH (5V) = CHARGING LOGIC LOW (0V) = DISCHARGING B 1/4 LT1491 V VOUT = OUT AMPS (RS)(RG /RA)(GAIN) GAIN D 1/4 LT1491 VOUT – 10k 90.9k S1 = OPEN, GAIN = 1 S1 = CLOSED, GAIN = 10 RA = RB VS = 5V, 0V 1490/91 TA01 1 LT1490/LT1491 W W W AXI U U ABSOLUTE RATI GS (Note 1) Total Supply Voltage (V + to V –) .............................. 44V Input Differential Voltage ......................................... 44V Input Current ...................................................... ±25mA Output Short-Circuit Duration (Note 2) .........Continuous Operating Temperature Range ................ – 40°C to 85°C Junction Temperature ........................................... 150°C Specified Temperature Range (Note 3) .. – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C U W U PACKAGE/ORDER INFORMATION (For new designs, use the LT1490A or LT1491A) ORDER PART NUMBER TOP VIEW OUT A –IN A 8 1 2 V+ 7 OUT B 6 –IN B 5 +IN B A +IN A V– 3 B 4 MS8 PACKAGE N8 PACKAGE 8-LEAD MSOP 8-LEAD PDIP S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 250°C/ W (MS8) TJMAX = 150°C, θJA = 130°C/ W (N8) TJMAX = 150°C, θJA = 190°C/ W (S8) LT1490CMS8 LT1490CN8 LT1490CS8 LT1490IN8 LT1490IS8 OUT A 1 –IN A 2 +IN A 3 V+ 4 +IN B 5 –IN B 6 MS8 PART MARKING OUT B 7 LTBB S8 PART MARKING ORDER PART NUMBER TOP VIEW 14 OUT D A D LT1491CN LT1491CS LT1491IN LT1491IS 13 –IN D 12 +IN D 11 V – 10 +IN C B C 9 – IN C 8 OUT C N PACKAGE S PACKAGE 14-LEAD PDIP 14-LEAD PLASTIC SO TJMAX = 150°C, θJA = 110°C/ W (N) TJMAX = 150°C, θJA = 150°C/ W (S) 1490 1490I Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V; VCM = VOUT = half supply, unless otherwise noted. (Note 3) SYMBOL VOS PARAMETER Input Offset Voltage CONDITIONS LT1490 N Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C LT1490 S Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C LT1491 N Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C VOS TC Input Offset Voltage Drift IOS Input Offset Current IB 2 TYP 220 MAX 800 1000 1100 UNITS µV µV µV 220 950 1200 1300 1100 1350 1450 µV µV µV µV µV µV 350 1450 1650 1750 µV µV µV ● ● ● ● 300 ● ● LT1490CMS8 Package, LT1491 S Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ● ● 0°C ≤ TA ≤ 70°C (Note 7) –40°C ≤ TA ≤ 85°C (Note 7) ● ● 2 2 4 4 ● ● 0.2 VCM = 44V (Note 4) 0.8 0.8 nA µA ● ● 4 4 0.1 1 8 10 nA µA nA Input Bias Current Input Noise Voltage MIN VCM = 44V (Note 4) VS = 0V 0.1Hz to 10Hz µV/°C µV/°C µVP-P LT1490/LT1491 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V; VCM = VOUT = half supply, unless otherwise noted. (Note 3) SYMBOL PARAMETER CONDITIONS en in Input Noise Voltage Density Input Noise Current Density f = 1kHz f = 1kHz RIN Input Resistance Differential Common Mode, VCM = 0V to 44V CIN Input Capacitance Input Voltage Range Common Mode Rejection Ratio (Note 4) VCM = 0V to VCC – 1V VCM = 0V to 44V AVOL Large-Signal Voltage Gain VS = 3V, VO = 500mV to 2.5V, RL = 10k 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C VS = 5V, VO = 500mV to 4.5V, RL = 10k 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C VOH ISC PSRR IS GBW SR Output Voltage Swing Low Output Voltage Swing High Short-Circuit Current (Note 2) MAX 50 0.03 6 4 17 11 ● 0 ● ● 84 80 98 98 200 133 100 400 250 200 1500 ● ● ● ● UNITS nV/√Hz pA/√Hz MΩ MΩ 44 pF V dB dB V/mV V/mV V/mV V/mV V/mV V/mV 1500 VS = 3V, No Load VS = 3V, ISINK = 5mA ● ● 22 250 50 450 mV mV VS = 5V, No Load VS = 5V, ISINK = 5mA VS = 5V, ISINK = 10mA VS = 3V, No Load VS = 3V, ISOURCE = 5mA VS = 5V, No Load VS = 5V, ISOURCE = 10mA ● ● 22 250 330 2.978 2.6 4.978 4.6 50 500 500 mV mV mV V V V V ● ● ● ● 2.95 2.55 4.95 4.30 VS = 3V, Short to GND VS = 3V, Short to VCC 10 10 15 30 mA mA VS = 5V, Short to GND VS = 5V, Short to VCC 15 15 25 30 mA mA 84 98 2 dB V 18 27 40 Power Supply Rejection Ratio Minimum Operating Supply Voltage VS = 2.5V to 12.5V, VCM = VO = 1V Reverse Supply Voltage Supply Current per Amplifier (Note 5) Gain Bandwidth Product (Note 4) IS = – 100µA per Amplifier Slew Rate (Note 6) TYP 4.6 CMRR VOL MIN ● ● ● ● f = 1kHz 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C 110 100 90 180 ● ● AV = – 1, RL = ∞ 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C 0.035 0.031 0.030 0.06 ● ● 2.5 50 55 V µA µA kHz kHz kHz V/µs V/µs V/µs 3 LT1490/LT1491 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±15V, VCM = 0V, VOUT = 0V, unless otherwise noted. (Note 3) SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT1490 N, S Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C MIN TYP MAX UNITS 250 1200 1400 1500 ● ● µV µV µV LT1491 N Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ● ● 350 1250 1500 1600 µV µV µV LT1490CMS8 Package, LT1491 S Package 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ● ● 400 1600 1850 1950 µV µV µV 0°C ≤ TA ≤ 70°C (Note 7) – 40°C ≤ TA ≤ 85°C (Note 7) ● ● 3 3 6 6 µV/°C µV/°C VOS TC Input Offset Voltage Drift IOS Input Offset Current ● 0.2 0.8 nA IB Input Bias Current ● 4 8 nA Input Noise Voltage 0.1Hz to 10Hz 1 µVP-P en Input Noise Voltage Density f = 1kHz 50 nV/√Hz in Input Noise Current Density f = 1kHz 0.03 pA/√Hz RIN Input Resistance Differential Common Mode, VCM = – 15V to 14V CIN Input Capacitance Input Voltage Range 6 17 15000 MΩ MΩ 4.6 pF ● – 15 CMRR Common Mode Rejection Ratio VCM = – 15V to 29V ● 80 98 29 dB V AVOL Large-Signal Voltage Gain VO = ±14V, RL = 10k 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C 100 75 50 250 ● ● V/mV V/mV V/mV ±14.9 ±14.5 ±14.5 ±14.978 ±14.750 ±14.670 VO Output Voltage Swing No Load IOUT = ±5mA IOUT = ±10mA ISC Short-Circuit Current (Note 2) Short to GND 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ±20 ±15 ±10 ±25 ● ● mA mA mA VS = ±1.25V to ±22V ● 88 98 dB PSRR Power Supply Rejection Ratio IS Supply Current per Amplifier ● ● 50 ● GBW SR Gain Bandwidth Product Slew Rate f = 1kHz 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C AV = – 1, RL = ∞, VO = ±10V, Measure at VO = ±5V 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C 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 LT1490C/LT1491C are guaranteed to meet specified performance from 0°C to 70°C. The LT1490C/LT1491C are designed, characterized and expected to meet specified performance from – 40°C to 85°C but are not tested or QA sampled at these temperatures. 4 ● ● ● ● V V V 70 85 µA µA 125 110 100 200 kHz kHz kHz 0.0375 0.07 V/µs 0.0330 0.0300 V/µs V/µs The LT1490I/LT1491I are guaranteed to meet specified performance from – 40°C to 85°C. Note 4: VS = 5V limits are guaranteed by correlation to VS = 3V and VS = ±15V tests. Note 5: VS = 3V limits are guaranteed by correlation to VS = 5V and VS = ±15V tests. Note 6: Guaranteed by correlation to slew rate at VS = ±15V and GBW at VS = 3V and VS = ±15V tests. Note 7: This parameter is not 100% tested. LT1490/LT1491 U W TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage TA = 125°C 60 TA = 25°C 50 40 TA = –55°C 30 20 10 0 5 0 10 15 20 25 30 35 40 TOTAL SUPPLY VOLTAGE (V) 400 6000 300 4000 200 100 TA = –55°C TA = 25°C 0 –100 –200 –300 – 400 45 TA = – 55°C 0.01 0.1 1 SOURCING LOAD CURRENT (mA) TA = 125°C 0.1 TA = 25°C TA = – 55°C 0.01 0.1 1 SINKING LOAD CURRENT (mA) 2 7 8 50 40 30 9 10 1490 G07 OUTPUT HIGH 20 OUTPUT LOW 10 0 10 20 30 40 50 60 70 80 90 100 INPUT OVERDRIVE (mV) Input Noise Current vs Frequency 0.35 INPUT NOISE CURRENT DENSITY (pA/√Hz) INPUT NOISE VOLTAGE DENSITY (nV/√Hz) 4 5 6 TIME (SEC) 60 1490/91 G06 80 3 70 Noise Voltage Density vs Frequency 70 60 50 40 30 1 80 0 10 VS = ± 2.5V NO LOAD 90 1490/90 G05 0.1Hz to 10Hz Noise Voltage 44 1490/91 G03 100 1490/90 G04 0 4.4 5.2 5.6 4.8 COMMON MODE VOLTAGE (V) Output Saturation Voltage vs Input Overdrive VS = ± 2.5V VOD = 30mV 0.01 0.001 10 VS = ±2.5V TA = 25°C TA = 125°C –10 4.0 5 OUTPUT SATURATION VOLTAGE (mV) OUTPUT SATURATION VOLTAGE (V) TA = 25°C NOISE VOLTAGE (400nV/DIV) OUTPUT SATURATION VOLTAGE (V) 1 TA = 125°C 0.01 0.001 10 Output Saturation Voltage vs Load Current (Output Low) VS = ± 2.5V VOD = 30mV TA = –55°C 20 1490/91 G02 Output Saturation Voltage vs Load Current (Output High) 0.1 30 0 1 3 4 2 TOTAL SUPPLY VOLTAGE (V) 0 VS = 5V, 0V 2000 TA = 125°C 1490/91 G01 1 INPUT BIAS CURRENT (nA) CHANGE IN INPUT OFFSET VOLTAGE (µV) SUPPLY CURRENT PER AMPLIFIER (µA) 80 70 Input Bias Current vs Common Mode Voltage Minimum Supply Voltage 1 10 100 FREQUENCY (Hz) 1k 1490/91 G08 0.30 0.25 0.20 0.15 0.10 0.05 0 1 10 100 FREQUENCY (Hz) 1k 1490/91 G09 5 LT1490/LT1491 U W TYPICAL PERFOR A CE CHARACTERISTICS Gain and Phase Shift vs Frequency Gain Bandwidth Product vs Temperature 40 30 20 20 0 GAIN 10 –20 0 – 40 –10 – 60 –20 – 80 10 100 FREQUENCY (kHz) 200 VS = ±15V 180 VS = ±3V 160 50 25 0 75 TEMPERATURE (°C) 40 200 30 180 170 20 RL = 10k f = 1kHz 160 COMMON MODE REJECTION RATIO (dB) 220 PHASE MARGIN (DEG) GAIN BANDWIDTH PRODUCT (kHz) 50 GAIN BANDWIDTH 0 5 10 15 20 25 30 35 40 TOTAL SUPPLY VOLTAGE (V) 100 VS = ±15V 80 VS = ±1.5V 60 40 10 FREQUENCY (kHz) PHASE MARGIN 250 40 30 20 NEGATIVE SUPPLY 10 0 –10 10 FREQUENCY (kHz) 1 100 1490/91 G15 Output Impedance vs Frequency 10k VS = ±15V VS = ± 2.5V 120 70 60 200 POSITIVE SUPPLY 50 100 50 GAIN BANDWIDTH 150 40 100 30 110 OUTPUT IMPEDANCE (Ω) 300 130 CHANNEL SEPARATION (dB) VS = ± 2.5V AV = –1 RF = RG = 100k f = 1kHz 60 Channel Separation vs Frequency 80 PHASE MARGIN (DEG) GAIN BANDWIDTH PRODUCT (kHz) 350 VS = ±2.5V 70 1490 G14 1490/91 G13 Gain Bandwidth Product and Phase Margin vs Load Resistance 125 –20 1 45 100 PSRR vs Frequency 80 20 10 150 50 25 0 75 TEMPERATURE (°C) 1490/91 G12 120 240 190 0.04 –50 –25 125 100 CMRR vs Frequency 210 FALLING, VS = ±1.5V 1490/91 G11 60 230 FALLING, VS = ±15V 120 Gain Bandwidth Product and Phase Margin vs Supply Voltage PHASE MARGIN RISING, VS = ±1.5V 0.08 0.06 140 1490/91 G10 250 RISING, VS = ±15V 0.10 220 100 –50 –25 –100 1000 –30 1 f = 1kHz PHASE SHIFT (DEG) GAIN (dB) 240 60 PHASE 40 80 POWER SUPPLY REJECTION RATIO (dB) 50 100 Slew Rate vs Temperature 0.12 SLEW RATE (V/µs) VS = ±2.5V GAIN BANDWIDTH PRODUCT (kHz) 70 60 260 100 90 80 70 60 1k AV = 100 100 AV = 10 10 1 AV = 1 50 50 1 10 LOAD RESISTANCE (kΩ) 20 100 1490/91 G16 6 40 0.1 1 10 FREQUENCY (kHz) 100 1490/91 G17 0.1 0.1 1 10 FREQUENCY (kHz) 100 1490/91 G18 LT1490/LT1491 U W TYPICAL PERFOR A CE CHARACTERISTICS Undistorted Output Swing vs Frequency 35 10 VS = ±2.5V 0 –2 –4 –6 1 10 FREQUENCY (kHz) 50 40 AV = 1 AV = 2 AV = 10 AV = 5 30 10 20 40 60 80 100 120 140 160 SETTLING TIME (µs) 10 100 1000 CAPACITIVE LOAD (pF) 10000 1490/91 G19 1490/91 F20 1490/91 G21 Total Harmonic Distortion + Noise vs Frequency Total Harmonic Distortion + Noise vs Load Resistance Total Harmonic Distortion + Noise vs Output Voltage 0.01 1 RL = 10k VCM = HALF SUPPLY f = 1kHz 1 VS = ±1.5V VIN = ±1V 0.1 VS = 3V, 0V VIN = 0.5V TO 2.5V AV = –1 VS = ±1.5V 0.1 AV = 1 VS = 3V, 0V VS = 3V, 0V VIN = 0.2V TO 2.2V AV = 1 1 0.1 FREQUENCY (kHz) 10 0.001 0.1 AV = –1 VS = 3V, 0V 0.001 10 1 LOAD RESISTANCE TO GROUND (kΩ) 1490/91 G22 Open-Loop Gain AV = 1 VS = ±1.5V 0.01 0.01 AV = –1 0.001 0.01 10 VS = 3V TOTAL AV = 1 VIN = 2VP-P AT 1kHz THD + NOISE (%) 10 VS = 3V, 0V VOUT = 2VP-P VCM = 1.2V RL = 50k 0.1 CHANGE IN INPUT OFFSET VOLTAGE (100µV/DIV) 60 0 0 100 70 20 AV = –1 AV = 1 –10 THD + NOISE (%) 1 2 –8 0 0.1 10 80 AV = 1 4 VS = 5V, 0V ISOURCE = 170µA 90 OVERSHOOT (%) OUTPUT STEP (V) OUTPUT SWING (VP-P) 15 100 AV = –1 6 20 Capacitive Load Handling, Overshoot vs Capacitive Load VS = ±15V 8 25 5 THD + NOISE (%) 10 DISTORTION ≤1% VS = ±15V 30 Settling Time to 0.1% vs Output Step 100 0 1 2 OUTPUT VOLTAGE (VP-P) 1490/91 G24 1490/91 G23 Large-Signal Response 3 Small-Signal Response VS = ±15V RL = 2k RL = 10k RL = 50k –10V 0V 10V OUTPUT VOLTAGE (5V/DIV) 1490/91 G25 VS = ±15V AV = –1 1490/91 G26 VS = ±15V AV = 1 1490/91 G27 7 LT1490/LT1491 U W U U APPLICATIO S I FOR ATIO Supply Voltage The positive supply pin of the LT1490/LT1491 should be bypassed with a small capacitor (about 0.01µF) within an inch of the pin. When driving heavy loads an additional 4.7µF electrolytic capacitor should be used. When using split supplies, the same is true for the negative supply pin. The LT1490/LT1491 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 LT1490/LT1491 can be shut down by removing V +. In this condition the input bias current is less than 0.1nA, even if the inputs are 44V above the negative supply. The inputs are protected against excursions as much as 22V 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 22V 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 LT1490/LT1491 is affected by input overdrive as shown in the typical performance curves. When monitoring voltages within 100mV of either rail, gain should be taken to keep the output from clipping. When operating the LT1490/LT1491 on total supplies of 30V or more, the supply must not be brought up faster than 1µs. 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. 5Ω of resistance in the supply or the bypass capacitor will dampen the tuned circuit enough to limit the rise time. The output of the LT1490/LT1491 can be pulled up to 18V beyond V + with less than 1nA of leakage current, provided that V + is less than 0.5V. Inputs The LT1490/LT1491 is internally compensated to drive at least 200pF of capacitance under any output loading conditions. A 0.22µF capacitor in series with a 150Ω resistor between the output and ground will compensate these amplifiers for larger capacitive loads, up to 10,000pF, at all output currents. The LT1490/LT1491 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 – 4nA. 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 18nA. 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 600µV. A Schottky diode in the collector of each NPN transistor of the NPN input stage allows the LT1490/LT1491 to operate with either or both of its inputs above V +. At about 0.3V above V + the NPN input transistor is fully saturated and the input bias current is typically 4µA at room temperature. The input offset voltage is typically 700µV when operating above V +. The LT1490/LT1491 will operate with its inputs 44V above V – regardless of V +. 8 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. 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 LT1490 switches 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 LT1490/LT1491 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. LT1490/LT1491 U W U U APPLICATIO S I FOR ATIO Gain mance 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. The open-loop gain is almost independent of load when the output is sourcing current. This optimizes perfor- U TYPICAL APPLICATIO S Square Wave Oscillator Optional Output Compensation for Capacitive Loads Greater Than 200pF 59k 5V 100k + 100k + VIN 1/2 LT1490 1/2 LT1490 VOUT CL ≤ 10,000pF – – R 50k C 0.1µF 1490/91 TA02 0.22µF 150Ω f= 1 2RC VOUT = 5VP-P WITH 5V SUPPLY IS = 200µA 1490/91 TA04 AT VS = 5V, R = 50k, C = 1nF OUTPUT IS 5kHz SLEW LIMITED TRIANGLE WAVE W W SI PLIFIED SCHE ATIC V+ Q2 Q1 D1 R1 30k Q3 Q22 D3 D2 R2 1k Q4 Q19 – IN Q17 Q7 R3 1k + Q8 Q11 OUT Q12 Q16 +IN 2µA Q6 Q18 Q15 Q9 Q5 Q20 D4 D5 Q10 Q13 Q14 R4 40k Q21 R5 40k V– ONE AMPLIFIER 1490/91 SS 9 LT1490/LT1491 U PACKAGE DESCRIPTIO Dimensions in inches (millimeters) unless otherwise noted. MS Package 8-Lead Plastic MSOP (LTC DWG # 05-08-1660) 0.040 ± 0.006 (1.02 ± 0.15) 0.007 (0.18) 0.118 ± 0.004* (3.00 ± 0.102) 0.034 ± 0.004 (0.86 ± 0.102) 8 7 6 5 0° – 6° TYP SEATING PLANE 0.012 (0.30) 0.0256 REF (0.65) BSC 0.021 ± 0.006 (0.53 ± 0.015) 0.118 ± 0.004** (3.00 ± 0.102) 0.193 ± 0.006 (4.90 ± 0.15) 0.006 ± 0.004 (0.15 ± 0.102) MSOP (MS8) 1098 1 * 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 4 2 3 N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) ( 0.045 – 0.065 (1.143 – 1.651) +0.889 8.255 –0.381 0.130 ± 0.005 (3.302 ± 0.127) 0.065 (1.651) TYP +0.035 0.325 –0.015 ) 0.400* (10.160) MAX 8 7 6 5 1 2 3 4 0.255 ± 0.015* (6.477 ± 0.381) 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 ± 0.003 (0.457 ± 0.076) 0.100 (2.54) BSC N8 1098 *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) 0.010 – 0.020 × 45° (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.053 – 0.069 (1.346 – 1.752) 0°– 8° TYP 0.016 – 0.050 (0.406 – 1.270) 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 10 8 7 6 5 0.004 – 0.010 (0.101 – 0.254) 0.050 (1.270) BSC 0.150 – 0.157** (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) SO8 1298 1 2 3 4 LT1490/LT1491 U PACKAGE DESCRIPTIO 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 1 2 3 4 5 6 7 0.255 ± 0.015* (6.477 ± 0.381) 0.130 ± 0.005 (3.302 ± 0.127) 0.300 – 0.325 (7.620 – 8.255) 0.045 – 0.065 (1.143 – 1.651) 0.020 (0.508) MIN 0.065 (1.651) TYP 0.009 – 0.015 (0.229 – 0.381) +0.035 0.325 –0.015 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) ( +0.889 8.255 –0.381 ) 0.018 ± 0.003 (0.457 ± 0.076) 0.125 (3.175) MIN N14 1098 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 0.010 – 0.020 × 45° (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 2 3 4 5 6 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) 0.014 – 0.019 (0.355 – 0.483) TYP 7 0.050 (1.270) BSC *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. S14 1298 11 LT1490/LT1491 U TYPICAL APPLICATIO Ring-Tone Generator 60V R16 100k R2 47k R3 10k C2 0.47µF 3 + R1 1/4 LT1491 33k 2 1 D1 1N4148 R5 100k 5 – 7 R9 300k R7 16k – R11 10k 10 Z1 15V 100k + 1/4 LT1491 C4 0.068µF 9 8 13 – C1 1µF R8 620k CADENCE OSCILLATOR R10 620k R12 SMOOTHING FILTER 10k R14 10k R13 130k R15 47k 20Hz OSCILLATOR C5 0.01µF + R24 11 420 14 C7 47µF R18 100Ω R26 2k R23 4.7k OPTO1* R25 4.7k Q5 2N3904 Z2 15V *LED OF OPTO1 ILLUMINATES WHEN THE PHONE IS OFF THE HOOK SEE DESIGN NOTE DN134 FOR AN EXPLANATION OF THE CIRCUIT R17 620Ω 4 – 1/4 LT1491 12 R4 1.6M Q3 2N3904 C3 0.047µF + 1/4 LT1491 6 Q1 IRF628 R6 10k Q2 IRF9620 POWER AMPLIFIER –180V R20 100k R19 620Ω UP TO LOAD TEN PHONES Q4 2N3906 R21 150Ω C6 0.033µF 1490/1491 TA03 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1078/LT1079 Dual/Quad 55µA Max, Single Supply, Precision Op Amps Input/Output Common Mode Includes Ground, 70µV VOS(MAX) and 2.5µV/°C Drift (Max), 200kHz GBW, 0.07V/µs Slew Rate LTC1152 Rail-to-Rail Input, Rail-to-Rail Output, Zero-Drift Amplifier High DC Accuracy, 10µV VOS(MAX), 100nV/°C, 1MHz GBW, 1V/µs Slew Rate, Supply Current 2.2mA (Max), Single Supply, Can Be Configured for C-LoadTM Operation LT1178/LT1179 Dual/Quad 17µA Max, Single Supply, Precison Op Amps Input/Output Common Mode Includes Ground, 70µV VOS(MAX) and 4µV/°C Drift (Max), 85kHz GBW, 0.04V/µs Slew Rate LT1366/LT1367 Dual/Quad Precision, Rail-to-Rail Input and Output Op Amps 475µV VOS(MAX), 500V/mV AVOL(MIN), 400kHz GBW LT1490A/LT1491A Dual/Quad Micropower Rail-to-Rail Precision Op Amps 500µV VOS(MAX), Improved Version of the LT1490/LT1491 C-Load is a trademark of Linear Technology Corporation. 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ● (408) 432-1900 FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com 14901fb LT/LCG 0600 2K REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1996