LT1632CN8

LT1632/LT1633 45MHz, 45V/µs, Dual/Quad Rail-to-Rail Input and Output Precision Op Amps FEATURES s s s s s s s s s s s s s s DESCRIPTION The LT ®1632/LT1633 are dual/quad, rail-to-rail input and output op amps with a 45MHz gain-bandwidth product and a 45V/µs slew rate. The LT1632/LT1633 have excellent DC precision over the full range of operation. Input offset voltage is typically less than 400µV and the minimum open-loop gain of 0.8 million into a 10k load virtually eliminates all gain error. Common mode rejection is typically 83dB over the full railto-rail input range when on a single 5V supply for excellent noninverting performance. The LT1632/LT1633 maintain their performance for supplies from 2.7V to 36V and are specified at 3V, 5V and ± 15V supplies. The inputs can be driven beyond the supplies without damage or phase reversal of the output. The output delivers load currents in excess of 35mA. The LT1632 is available in 8-pin PDIP and SO packages with the standard dual op amp pinout. The LT1633 features the standard quad op amp configuration and is available in a 14-pin plastic SO package. These devices can be used as plug-in replacements for many standard op amps to improve input/output range and performance. , LTC and LT are registered trademarks of Linear Technology Corporation. Gain-Bandwidth Product: 45MHz Slew Rate: 45V/µs Low Supply Current per Amplifier: 4.3mA Input Common Mode Range Includes Both Rails Output Swings Rail-to-Rail Input Offset Voltage, Rail-to-Rail: 1350µV Max Input Offset Current: 440nA Max Input Bias Current: 2.2µA Max Open-Loop Gain: 800V/mV Min Low Input Noise Voltage: 12nV/√Hz Typ Low Distortion: – 92dBc at 100kHz Wide Supply Range: 2.7V to ± 15V Large Output Drive Current: 35mA Min Dual in 8-Pin PDIP and SO Packages APPLICATIONS s s s s s Active Filters Rail-to-Rail Buffer Amplifiers Driving A/D Converters Low Voltage Signal Processing Battery-Powered Systems TYPICAL APPLICATION Frequency Response Single Supply, 40dB Gain, 550kHz Instrumentation Amplifier R2 2k R1 20k R5 432Ω R4 20k 50 40 30 20 VOLTAGE GAIN (dB) 10 0 –10 –20 –30 –40 –50 –60 –70 100 1k 10k 100k FREQUENCY (Hz) VS = 3V AV = 100 1M 10M COMMON MODE INPUT 1/2 LT1632 VIN– + VIN+ – R3 2k 3V 1/2 LT1632 VOUT 1630/31 F02 U U U DIFFERENTIAL INPUT + – 1632/33 TA02 1 LT1632/LT1633 ABSOLUTE MAXIMUM RATINGS Total Supply Voltage (V + to V –) ............................. 36V Input Current ..................................................... ±10mA Output Short-Circuit Duration (Note 2) ........ Continuous Operating Temperature Range ................ – 40°C to 85°C PACKAGE/ORDER INFORMATION TOP VIEW OUT A 1 – IN A 2 + IN A 3 V– 4 N8 PACKAGE 8-LEAD PDIP A B ORDER PART NUMBER 8 7 6 5 V+ OUT B – IN B + IN B LT1632CN8 LT1632CS8 S8 PART MARKING 1632 S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 130°C/ W (N8) TJMAX = 150°C, θJA = 190°C/ W (S8) Consult factory for Military and Industrial grade parts. ELECTRICAL CHARACTERISTICS TA = 25°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. SYMBOL PARAMETER VOS ∆VOS IB ∆ IB Input Offset Voltage Input Offset Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS en in CIN AVOL CMRR Input Offset Current Input Offset Current Shift Input Noise Voltage Input Noise Voltage Density Input Noise Current Density Input Capacitance Large-Signal Voltage Gain Common Mode Rejection Ratio VS = 5V, VO = 300mV to 4.7V, RL = 10k VS = 3V, VO = 300mV to 2.7V, RL = 10k VS = 5V, VCM = V – to V + VS = 3V, VCM = V – to V + 450 350 70 66 CONDITIONS VCM VCM = V – VCM = V – to V + V –, V + (Note 5) 0 – 2.2 VCM VCM = V – VCM = V – to V + VCM = V + (Note 5) VCM = V – (Note 5) VCM = V + VCM = V – VCM = V – to V + 0.1Hz to 10Hz f = 1kHz f = 1kHz = V+ = V+ MIN TYP 400 400 350 500 1.15 – 1.15 2.3 50 50 40 40 80 400 12 1.6 5 2000 1500 83 81 MAX 1350 1350 1500 2300 2.2 0 4.4 880 880 440 440 880 UNITS µV µV µV µV µA µA µA nA nA nA nA nA nVP-P nV/√Hz pA/√Hz pF V/mV V/mV dB dB Input Offset Voltage Match (Channel-to-Channel) VCM = 2 U U W WW U W (Note 1) Specified Temperature Range (Note 4) ..... – 40°C to 85°C Junction Temperature .......................................... 150°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C TOP VIEW OUTA 1 – IN A 2 + IN A 3 V+ 4 + IN B 5 – IN B 6 OUT B 7 B C A D 14 OUT D 13 – IN D 12 + IN D 11 V – 10 + IN C 9 8 – IN C OUT C ORDER PART NUMBER LT1633CS S PACKAGE 14-LEAD PLASTIC SO TJMAX = 150°C, θJA = 150°C/ W LT1632/LT1633 ELECTRICAL CHARACTERISTICS TA = 25°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. SYMBOL PARAMETER CMRR Match (Channel-to-Channel) (Note 5) PSRR Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) Minimum Supply Voltage (Note 9) VOL Output Voltage Swing Low (Note 6) CONDITIONS VS = 5V, VCM VS = 3V, VCM = V – to V + VS = 2.7V to 12V, VCM = VO = 0.5V VS = 2.7V to 12V, VCM = VO = 0.5V VCM = VO = 0.5V No Load ISINK = 0.5mA ISINK = 25mA, VS = 5V ISINK = 20mA, VS = 3V No Load ISOURCE = 0.5mA ISOURCE = 20mA, VS = 5V ISOURCE = 15mA, VS = 3V VS = 5V VS = 3V f = 100kHz VS = 5V, AV = – 1, RL = Open, VO = 4V VS = 3V, AV = – 1, RL = Open VS = 5V, AV = 1, RL = 1k, 0.01%, VSTEP = 2V ± 20 ± 15 22 13 11 = V – to V+ MIN 65 61 82 79 TYP 85 82 100 101 2.6 15 32 600 500 16 42 910 680 ± 40 ± 30 4.3 45 27 22 400 5.2 2.7 30 60 1200 1000 40 80 1800 1400 MAX UNITS dB dB dB dB V mV mV mV mV mV mV mV mV mA mA mA MHz V/µs V/µs ns VOH Output Voltage Swing High (Note 6) ISC IS GBW SR tS Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate (Note 8) Settling Time 0°C < TA < 70°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. SYMBOL PARAMETER VOS VOS TC ∆VOS IB ∆IB Input Offset Voltage Input Offset Voltage Drift (Note 3) VCM = V + – 0.1V Input Offset Voltage Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS AVOL CMRR Input Offset Current Input Offset Current Shift Large-Signal Voltage Gain Common Mode Rejection Ratio CMRR Match (Channel-to-Channel) (Note 5) PSRR Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) VCM = V – + 0.2V to V + – 0.1V V – + 0.2V, V + – 0.1V (Note 5) VCM = V + – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VCM = V + – 0.1V (Note 5) VCM = V – + 0.2V (Note 5) VCM = V + – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VS = 5V, VO = 300mV to 4.7V, RL = 10k VS = 3V, VO = 300mV to 2.7V, RL = 10k VS = 5V, VCM = V – + 0.2V to V + – 0.1V VS = 3V, VCM = V – + 0.2V to V + – 0.1V VS = 5V, VCM = V – + 0.2V to V + – 0.1V VS = 3V, VCM = V – + 0.2V to V + – 0.1V VS = 3V to 12V, VCM = VO = 0.5V VS = 3V to 12V, VCM = VO = 0.5V Input Offset Voltage Match (Channel-to-Channel) VCM = CONDITIONS VCM = V + – 0.1V VCM = V – + 0.2V q q q q q q q q q q q q q q q q q q q q q q MIN TYP 600 600 8 2.5 400 700 MAX 2000 2000 15 7 2300 3750 2.6 0 5.2 1040 1040 520 520 1040 UNITS µV µV µV/°C µV/°C µV µV µA µA µA nA nA nA nA nA V/mV V/mV dB dB dB dB dB dB 0 – 2.6 1.3 – 1.3 2.6 50 50 40 40 80 300 200 67 61 62 57 81 77 1100 1000 81 77 78 73 94 95 3 LT1632/LT1633 ELECTRICAL CHARACTERISTICS 0°C < TA < 70°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. SYMBOL PARAMETER Minimum Supply Voltage (Note 9) VOL Output Voltage Swing Low (Note 6) CONDITIONS VCM = VO = 0.5V No Load ISINK = 0.5mA ISINK = 25mA, VS = 5V ISINK = 20mA, VS = 3V No Load ISOURCE = 0.5mA ISOURCE = 15mA, VS = 5V ISOURCE = 10mA, VS = 3V VS = 5V VS = 3V f = 100kHz VS = 5V, AV = – 1, RL = Open, VO = 4V VS = 3V, AV = – 1, RL = Open q q q q q q q q q q q q q q q MIN TYP 2.6 18 37 700 560 16 50 820 550 MAX 2.7 40 80 1400 1200 40 100 1600 1100 UNITS V mV mV mV mV mV mV mV mV mA mA VOH Output Voltage Swing High (Note 6) ISC IS GBW SR Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate (Note 8) ± 18 ± 13 20 13 10 ± 37 ± 26 4.9 41 26 21 6.0 mA MHz V/µs V/µs – 40°C < TA < 85°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. (Note 4) SYMBOL PARAMETER VOS VOS TC ∆VOS IB ∆IB Input Offset Voltage Input Offset Voltage Drift (Note 3) VCM = V + – 0.1V Input Offset Voltage Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS AVOL CMRR Input Offset Current Input Offset Current Shift Large-Signal Voltage Gain Common Mode Rejection Ratio CMRR Match (Channel-to-Channel) (Note 5) PSRR Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) Minimum Supply Voltage (Note 9) VOL Output Voltage Swing Low (Note 6) VCM = V – + 0.2V to V + – 0.1V V – + 0.2V, V + (Note 5) V + – 0.1V VCM = VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VCM = VCM = V – + 0.2V (Note 5) VCM = V + – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VS = 5V, VO = 300mV to 4.7V, RL = 10k VS = 3V, VO = 300mV to 2.7V, RL = 10k VS = 5V, VCM = V – + 0.2V to V + – 0.1V VS = 3V, VCM = V – + 0.2V to V + – 0.1V VS = 5V, VCM = V – + 0.2V to V + – 0.1V VS = 3V, VCM = V – + 0.2V to V + – 0.1V VS = 3V to 12V, VCM = VO = 0.5V VS = 3V to 12V, VCM = VO = 0.5V VCM = VO = 0.5V No Load ISINK = 0.5mA ISINK = 25mA, VS = 5V ISINK = 20mV, VS = 3V V + – 0.1V (Note 5) Input Offset Voltage Match (Channel-to-Channel) VCM = CONDITIONS VCM = V + – 0.1V VCM = V – + 0.2V q q q q q q q q q q q q q q q q q q q q q q q q q q q MIN TYP 700 700 8 2.5 475 750 MAX 2400 2400 15 7 2500 4000 3.0 0 6.0 1160 1160 580 580 1160 UNITS µV µV µV/°C µV/°C µV µV µA µA µA nA nA nA nA nA V/mV V/mV dB dB dB dB dB dB 0 – 3.0 1.46 – 1.46 2.92 70 70 75 75 50 250 200 65 60 62 57 79 75 1000 800 80 75 78 73 95 95 2.6 19 39 730 580 2.7 40 80 1500 1200 V mV mV mV mV 4 LT1632/LT1633 ELECTRICAL CHARACTERISTICS – 40°C < TA < 85°C, VS = 5V, 0V; VS = 3V, 0V; VCM = VOUT = half supply, unless otherwise noted. (Note 4) SYMBOL PARAMETER VOH Output Voltage Swing High (Note 6) CONDITIONS No Load ISOURCE = 0.5mA ISOURCE = 15mA, VS = 5V ISOURCE = 10mA, VS = 3V VS = 5V VS = 3V f = 100kHz VS = 5V, AV = –1, RL = Open, VO = 4V VS = 3V, AV = –1, RL = Open q q q q q q q q q q MIN TYP 16 55 860 580 MAX 40 110 1700 1200 UNITS mV mV mV mV mA mA ISC IS GBW SR Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate (Note 8) ± 17 ± 12 20 11 9 ± 36 ± 24 4.95 40 22 18 6.2 mA MHz V/µs V/µs TA = 25°C, VS = ± 15V, VCM = 0V, VOUT = 0V, unless otherwise noted. SYMBOL PARAMETER VOS ∆VOS IB ∆IB Input Offset Voltage Input Offset Voltage Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS en in CIN AVOL Input Offset Current Input Offset Current Shift Input Noise Voltage Input Noise Voltage Density Input Noise Current Density Input Capacitance Large-Signal Voltage Gain Channel Separation CMRR PSRR VOL Common Mode Rejection Ratio CMRR Match (Channel-to-Channel) (Note 5) Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) Output Voltage Swing Low (Note 6) CONDITIONS VCM = V + VCM = V – VCM = V – to V + VCM = VCM = VCM = VCM = V+ V– V + (Note 5) V – (Note 5) 0 – 2.2 MIN TYP 500 500 360 700 1.15 – 1.15 2.3 50 50 50 50 36 400 12 1.6 3 800 400 110 82 80 82 80 5000 2500 127 98 101 96 101 16 150 600 16 250 1200 35 300 1200 40 500 2400 MAX 2200 2200 2200 3500 2.2 0 4.4 880 880 440 440 880 UNITS µV µV µV µV µA µA µA nA nA nA nA nA nVP-P nV/√Hz pA/√Hz pF V/mV V/mV dB dB dB dB dB mV mV mV mV mV mV Input Offset Voltage Match (Channel-to-Channel) VCM = V –, V + (Note 5) VCM = V – to V + VCM = V + VCM = V – VCM = V – to V + 0.1Hz to 10Hz f = 1kHz f = 1kHz f = 100kHz VO = – 14.5V to 14.5V, RL = 10k VO = – 10V to 10V, RL = 2k VO = – 10V to 10V, RL = 2k VCM = V – to V + VCM = V – to V + VS = ± 5V to ± 15V VS = ± 5V to ± 15V No Load ISINK = 5mA ISINK = 25mA No Load ISOURCE = 5mA ISOURCE = 25mA VOH Output Voltage Swing High (Note 6) 5 LT1632/LT1633 ELECTRICAL CHARACTERISTICS TA = 25°C, VS = ± 15V, VCM = 0V, VOUT = 0V, unless otherwise noted. SYMBOL PARAMETER ISC IS GBW SR tS Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate Settling Time f = 100kHz AV = – 1, RL = Open, VO = ± 10V, Measure at VO = ± 5V 0.01%, VSTEP = 10V, AV = 1, RL = 1k 22 22 CONDITIONS MIN ± 35 TYP ± 70 4.6 45 45 575 6 MAX UNITS mA mA MHz V/µs ns 0°C < TA < 70°C, VS = ± 15V, VCM = 0V, VOUT = 0V, unless otherwise noted. SYMBOL PARAMETER VOS VOS TC ∆VOS IB ∆IB Input Offset Voltage Input Offset Voltage Drift (Note 3) VCM = V + – 0.1V Input Offset Voltage Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS AVOL Input Offset Current Input Offset Current Shift Large-Signal Voltage Gain Channel Separation CMRR PSRR VOL Common Mode Rejection Ratio CMRR Match (Channel-to-Channel) (Note 5) Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) Output Voltage Swing Low (Note 6) VCM = V – + 0.2V to V + – 0.1V VCM = VCM = V – + 0.2V V + – 0.1V Input Offset Voltage Match (Channel-to-Channel) VCM = V – + 0.2V, V + – 0.1V (Note 5) CONDITIONS VCM = VCM = V – + 0.2V V + – 0.1V q q q q q q q q q q q q q q q q q q q q q q q q q q q q q MIN TYP 800 800 10 5 500 800 MAX 2750 2750 17 11 2500 4000 2.6 0 5.2 1040 1040 520 520 1040 UNITS µV µV µV/°C µV/°C µV µV µA µA µA nA nA nA nA nA V/mV V/mV dB dB dB dB dB 0 – 2.6 1.3 – 1.3 2.6 70 70 70 70 140 VCM = V – + 0.2V to V + – 0.1V VCM = VCM = V – + 0.2V (Note 5) VCM = V + – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VO = – 14.5V to 14.5V, RL = 10k VO = – 10V to 10V, RL = 2k VO = – 10V to 10V, RL = 2k VCM = V – + 0.2V to V + – 0.1V VCM = V – + 0.2V to V + – 0.1V VS = ± 5V to ± 15V VS = ± 5V to ± 15V No Load ISINK = 5mA ISINK = 25mA No Load ISOURCE = 5mA ISOURCE = 25mA V + – 0.1V (Note 5) 600 300 110 81 77 80 74 4000 2000 125 96 95 94 95 21 180 680 15 300 1400 45 350 1400 40 600 2800 6.9 mV mV mV mV mV mV mA mA MHz V/µs VOH Output Voltage Swing High (Note 6) ISC IS GBW SR Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate f = 100kHz AV = – 1, RL = Open, VO = ± 10V, Measured at VO = ± 5V ± 28 20 21 ± 57 5.2 41 43 q q 6 LT1632/LT1633 ELECTRICAL CHARACTERISTICS – 40°C < TA < 85°C, VS = ± 15V, VCM = 0V, VOUT = 0V, unless otherwise noted. (Note 4) SYMBOL PARAMETER VOS VOS TC ∆VOS IB ∆IB Input Offset Voltage Input Offset Voltage Drift (Note 3) VCM = V + – 0.1V Input Offset Voltage Shift Input Bias Current Input Bias Current Shift Input Bias Current Match (Channel-to-Channel) IOS ∆IOS AVOL Input Offset Current Input Offset Current Shift Large-Signal Voltage Gain Channel Separation CMRR PSRR VOL Common Mode Rejection Ratio CMRR Match (Channel-to-Channel) (Note 5) Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 5) Output Voltage Swing Low (Note 6) VCM = V – + 0.2V to V + – 0.1V V – + 0.2V, V + – 0.1V (Note 5) V+ VCM = – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VCM = VCM = V – + 0.2V (Note 5) VCM = V + – 0.1V VCM = V – + 0.2V VCM = V – + 0.2V to V + – 0.1V VO = – 14.5V to 14.5V, RL = 10k VO = – 10V to 10V, RL = 2k VO = – 10V to 10V, RL = 2k VCM = V – + 0.2V to V + – 0.1V VCM = V – + 0.2V to V + – 0.1V VS = ± 5V to ± 15V VS = ± 5V to ± 15V No Load ISINK = 5mA ISINK = 25mA No Load ISOURCE = 5mA ISOURCE = 25mA V + – 0.1V (Note 5) Input Offset Voltage Match (Channel-to-Channel) VCM = CONDITIONS VCM = – 0.1V VCM = V – + 0.2V V+ q q q q q q q q q q q q q q q q q q q q q q q q q q q q q MIN TYP 1000 1000 10 5 500 850 MAX 3000 3000 17 11 2600 4000 2.8 0 5.6 1120 1120 560 560 1120 UNITS µV µV µV/°C µV/°C µV µV µA µA µA nA nA nA nA nA V/mV V/mV dB dB dB dB dB 0 – 2.8 1.4 – 1.4 2.8 75 75 60 60 120 500 250 110 81 77 80 74 5000 1800 124 96 95 93 95 23 187 700 16 300 1500 50 350 1400 40 600 3000 7 mV mV mV mV mV mV mA mA MHz V/µs VOH Output Voltage Swing High (Note 6) ISC IS GBW SR Short-Circuit Current Supply Current per Amplifier Gain-Bandwidth Product (Note 7) Slew Rate f = 100kHz AV = – 1, RL = Open, VO = ±10V, Measure at VO = ± 5V ± 27 20 18 ± 54 5.3 40 35 q q The q denotes specifications that apply over the full operating temperature range. Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: A heat sink may be required to keep the junction temperature below the absolute maximum rating when the output is shorted indefinitely. Note 3: This parameter is not 100% tested. Note 4: The LT1632C/LT1633C are guaranteed to meet specified performance from 0°C to 70°C and are designed, characterized and expected to meet these extended temperature limits, but are not tested at – 40°C and 85°C. Guaranteed I grade parts are available, consult factory. Note 5: Matching parameters are the difference between amplifiers A and D and between B and C on the LT1633; between the two amplifiers on the LT1632. Note 6: Output voltage swings are measured between the output and power supply rails. Note 7: VS = 3V, VS = ± 15V GBW limit guaranteed by correlation to 5V tests. Note 8: VS = 3V, VS = 5V slew rate limit guaranteed by correlation to ± 15V tests. Note 9: Minimum supply voltage is guaranteed by testing the change of VOS to be less than 250µV when the supply voltage is varied from 3V to 2.7V. 7 LT1632/LT1633 TYPICAL PERFORMANCE CHARACTERISTICS VOS Distribution, VCM = 0V (PNP Stage) 50 VS = 5V, 0V VCM = 0V 40 PERCENT OF UNITS (%) PERCENT OF UNITS (%) 30 30 PERCENT OF UNITS (%) 20 10 0 –1250 –750 250 750 –250 INPUT OFFSET VOLTAGE (µV) Supply Current vs Supply Voltage 6.0 SUPPLY CURRENT PER AMPLIFIER (mA) 5.5 5.0 4.5 4.0 3.5 TA = 125°C SUPPLY CURRENT PER AMPLIFIER (mA) INPUT BIAS CURRENT (µA) TA = 25°C TA = – 55°C 3.0 2.5 2.0 0 4 8 12 16 20 24 28 TOTAL SUPPLY VOTAGE (V) 32 36 1630/31 G01 Input Bias Current vs Temperature 2.8 2.0 INPUT BIAS CURRENT (µA) 1.2 NPN ACTIVE 0.4 0 –0.4 PNP ACTIVE –1.2 –2.0 VS = ± 15V VCM = – 15V VS = 5V, 0V VCM = 0V VS = 5V, 0V VCM = 5V VS = ± 15V VCM = 15V 10 SATURATION VOLTAGE (V) SATURATION VOLTAGE (V) –2.8 – 50 –35 – 20 –5 10 25 40 55 70 85 100 TEMPERATURE (°C) 1632/33 G04 8 UW VOS Distribution, VCM = 5V (NPN Stage) 50 VS = 5V, 0V VCM = 5V 40 40 50 ∆VOS Shift for VCM = 0V to 5V VS = 5V, 0V 30 20 20 10 10 1250 1632/33 G31 0 –1250 –750 250 750 –250 INPUT OFFSET VOLTAGE (µV) 1250 1632/33 G32 0 –1250 –750 250 750 –250 INPUT OFFSET VOLTAGE (µV) 1250 1632/33 G33 Supply Current vs Temperature 6.0 5.5 5.0 4.5 VS = 5V, 0V 4.0 3.5 3.0 2.5 25 50 75 –75 –50 –25 0 TEMPERATURE (°C) Input Bias Current vs Common Mode Voltage 2.0 VS = 5V, 0V 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –2 –1 TA = – 55°C 0 2 3 4 5 1 COMMON MODE VOLTAGE (V) 6 TA = 25°C TA = 125°C VS = ±15V 100 125 1632/33 G02 1632/33 G03 Output Saturation Voltage vs Load Current (Output Low) 10 VS = 5V, 0V Output Saturation Voltage vs Load Current (Output High) VS = 5V, 0V 1 TA = 125°C 0.1 TA = 25°C TA = – 55°C 1 TA = 125°C 0.1 TA = 25°C TA = – 55°C 0.01 0.01 0.1 1 10 LOAD CURRENT (mA) 100 1632/33 G05 0.01 0.01 0.1 1 10 LOAD CURRENT (mA) 100 1632/33 G06 LT1632/LT1633 TYPICAL PERFORMANCE CHARACTERISTICS Minimum Supply Voltage 600 CHANGE IN OFFSET VOLTAGE (µV) 500 NOISE VOLTAGE (nV/√Hz) 400 300 TA = 25°C 200 100 0 1 TA = 125°C TA = – 55°C 50 40 30 20 10 0 VCM = 2.5V PNP ACTIVE CURRENT NOISE (pA/√Hz) 4 2 3 TOTAL SUPPLY VOLTAGE (V) 0.1Hz to 10Hz Output Voltage Noise 80 OUTPUT VOLTAGE (200nV/DIV) VS = 5V, 0V VCM = VS /2 VOLTAGE GAIN (dB) GAIN BANDWIDTH (MHz) TIME (1SEC/DIV) 1632/33 G08 CMRR vs Frequency 120 POWER SUPPLY REJECTION RATIO (dB) COMMON MODE REJECTION RATIO (dB) 110 100 90 80 70 60 50 40 30 20 1k 10k 100k 1M FREQUENCY (Hz) 10M 1632/33 G12 VS = 5V, 0V 70 60 50 40 30 20 10 0 1k 10k CHANNEL SEPARATION (dB) VS = ± 15V UW 5 1632/33 G07 Noise Voltage Spectrum 70 VS = 5V, 0V 60 20 18 16 14 12 10 8 6 4 2 0 1 10 100 FREQUENCY (Hz) 1000 11632/33 G09 Noise Current Spectrum VS = 5V, 0V VCM = 4.25V NPN ACTIVE VCM = 4.25V NPN ACTIVE VCM = 2.5V PNP ACTIVE 1 10 100 FREQUENCY (Hz) 1000 1632/33 G10 Gain and Phase vs Frequency 70 60 50 40 30 20 10 0 –10 –20 0.01 0.1 1 10 FREQUENCY (MHz) GAIN PHASE 225 RL = 1k VS = 3V, 0V 180 VS = ± 15V 135 90 45 0 –45 –90 –135 –180 –225 100 1632/33 G11 Gain Bandwidth and Phase Margin vs Supply Voltage 120 105 90 PHASE MARGIN 75 60 GAIN BANDWIDTH 45 30 15 0 0 5 15 20 25 10 TOTAL SUPPLY VOLTAGE (V) 30 20 10 0 30 50 40 PHASE SHIFT (DEG) VCM = VS /2 80 70 60 PHASE MARGIN (DEG) 1632/33 G14 PSRR vs Frequency 100 90 80 POSITIVE SUPPLY VS = ±15V Channel Separation vs Frequency –40 –50 –60 –70 –80 –90 –100 –110 –120 –130 VS = ± 15V VOUT = ± 10VP-P RL = 2k NEGATIVE SUPPLY 100k 1M FREQUENCY (Hz) 10M 1632/33 G13 –140 10 100 1k 10k FREQUENCY (Hz) 100k 1M 1632/33 G15 9 LT1632/LT1633 TYPICAL PERFORMANCE CHARACTERISTICS Capacitive Load Handling 90 80 OVERSHOOT (%) 70 60 50 40 30 1 10 100 CAPACITIVE LOAD (pF) 1000 1632/33 G16 VS = 5V, 0V AV = 1 RL = 1k SLEW RATE (V/µs) RISING EDGE 40 FALLING EDGE 35 30 25 20 0 4 8 12 16 20 24 28 32 TOTAL SUPPLY VOLTAGE (V) 36 OUTPUT STEP (V) Open-Loop Gain 20 15 VS = ±15V 20 15 INPUT VOLTAGE (µV) INPUT VOLTAGE (µV) 5 0 –5 –10 –15 RL = 1k RL = 10k INPUT VOLTAGE (µV) 10 – 20 0 5 –20 –15 –10 – 5 10 OUTPUT VOLTAGE (V) Warm-Up Drift vs Time 100 CHANGE IN OFFSET VOLTAGE (µV) 0 –100 –200 –300 OUTPUT VOLTAGE SWING (VP-P) N8 PACKAGE, VS = 5V, 0V S8 PACKAGE, VS = 5V, 0V 3 THD + NOISE (%) N8 PACKAGE, VS = ±15V LT1633CS, VS = 5V, 0V S8 PACKAGE, VS = ±15V LT1633CS, VS = ±15V –400 –500 0 20 40 60 80 100 120 140 160 TIME AFTER POWER-UP (SEC) 1632/33 G22 10 UW 15 1632/33 G19 Slew Rate vs Supply Voltage 55 50 45 VOUT = 80% OF VS AV = – 1 10 8 6 4 2 0 –2 –4 –6 –8 –10 Output Step vs Settling Time to 0.01% VS = ±15V NONINVERTING INVERTING NONINVERTING INVERTING 0 0.25 0.75 0.50 SETTLING TIME (µs) 1.00 1632/33 G18 1632/33 G17 Open-Loop Gain 200 VS = 5V, 0V 150 100 50 0 –50 10 5 0 –5 –10 –15 20 –20 0 1 4 3 OUTPUT VOLTAGE (V) 2 5 6 RL = 1k RL = 10k Open-Loop Gain VS = ± 15V RL = 100Ω –100 –150 –200 –5 –4 –3 –2 –1 0 1 2 3 4 OUTPUT VOLTAGE (V) 5 6 7 1632/33 G20 1632/33 G21 Maximum Undistorted Output Signal vs Frequency 5 AV = 1 AV = – 1 Total Harmonic Distortion + Noise vs Frequency 1 VIN = 2VP-P RL = 10k VS = 3V, 0V AV = 1 4 0.1 0.01 VS = 5V, 0V AND 3V, 0V AV = – 1 VS = 5V, 0V AV = 1 2 1 VS = 5V, 0V 1 10 100 FREQUENCY (kHz) 1000 1630/31 G24 0.001 0 0.0001 0.1 1 10 FREQUENCY (kHz) 100 1632/33 G23 LT1632/LT1633 TYPICAL PERFORMANCE CHARACTERISTICS Harmonic Distortion vs Frequency 0 VS = 5V, 0V AV = 1 VIN = 2VP-P RL = 150Ω RL = 1k HARMONIC DISTORTION (dBc) –20 –40 3RD –60 2ND –80 3RD 2ND 200 1000 500 FREQUENCY (kHz) 2000 1632/33 G29 –100 100 Harmonic Distortion vs Frequency 0 VS = 5V, 0V AV = – 1 VIN = 2VP-P RL = 150Ω RL = 1k 3RD –60 3RD –80 HARMONIC DISTORTION (dBc) –20 –40 2ND –100 100 200 1000 500 FREQUENCY (kHz) APPLICATIONS INFORMATION Rail-to-Rail Input and Output The LT1632/LT1633 are fully functional for an input and output signal range from the negative supply to the positive supply. Figure 1 shows a simplified schematic of the amplifier. The input stage consists of two differential amplifiers, a PNP stage Q1/Q2 and an NPN stage Q3/Q4 that are active over different ranges of input common mode voltage. The PNP differential input pair is active for input common mode voltages VCM between the negative supply to approximately 1.5V below the positive supply. As VCM moves closer toward the positive supply, the transistor Q5 will steer the tail current I1 to the current mirror Q6/Q7, activating the NPN differential pair and the PNP pair becomes inactive for the rest of the input common mode range up to the positive supply. The output is configured with a pair of complementary common emitter stages Q14/Q15 that enables the output to swing from rail to rail. These devices are fabricated on Linear Technology’s proprietary complementary bipolar process to ensure similar DC and AC characteristics. Capacitors C1 and C2 form local feedback loops that lower the output impedance at high frequencies. Power Dissipation The LT1632/LT1633 amplifiers combine high speed and large output current drive in a small package. Because the U W UW 2ND 5V Small-Signal Response 5V Large-Signal Response VS = 5V, 0V AV = 1 RL = 1k 163233 G25 VS = 5V, 0V AV = 1 RL = 1k 1632/33 G26 ± 15V Small-Signal Response ± 15V Large-Signal Response VS = ±15V AV = 1 RL = 1k 2000 1632/33 G30 1000 1632/33 G27 VS = ±15V AV = 1 RL = 1k 1632/33 G28 U U 11 LT1632/LT1633 APPLICATIONS INFORMATION V+ R3 R4 R5 + IN R6 225Ω D1 D6 D8 D7 Q4 D2 Q5 Q3 VBIAS R7 – IN 225Ω D5 Q7 V– Q6 R1 R2 Q14 1632/33 F01 Figure 1. LT1632 Simplified Schematic Diagram amplifiers operate over a very wide supply range, it is possible to exceed the maximum junction temperature of 150°C in plastic packages under certain conditions. Junction temperature TJ is calculated from the ambient temperature TA and power dissipation PD as follows: LT1632CN8: TJ = TA + (PD • 130°C/W) LT1632CS8: TJ = TA + (PD • 190°C/W) LT1633CS: TJ = TA + (PD • 150°C/W) The power dissipation in the IC is the function of the supply voltage, output voltage and load resistance. For a given supply voltage, the worst-case power dissipation PDMAX occurs at the maximum supply current and when the output voltage is at half of either supply voltage (or the maximum swing if less than 1/2 supply voltage). Therefore PDMAX is given by: PDMAX = (VS • ISMAX) + (VS/2)2/RL To ensure that the LT1632/LT1633 are used properly, calculate the worst-case power dissipation, use the thermal resistance for a chosen package and its maximum junction temperature to derive the maximum ambient temperature. Example: An LT1632CS8 operating on ±15V supplies and driving a 500Ω, the worst-case power dissipation per amplifier is given by: 12 U W U U + I1 Q11 Q12 Q13 Q15 + I2 V– Q1 D3 Q9 D4 Q8 BUFFER AND OUTPUT BIAS C1 Q2 CC C2 OUT PDMAX = (30V • 5.6mA) + (15V – 7.5V)(7.5/500) = 0.168 + 0.113 = 0.281W If both amplifiers are loaded simultaneously, then the total power dissipation is 0.562W. The SO-8 package has a junction-to-ambient thermal resistance of 190°C/W in still air. Therefore, the maximum ambient temperature that the part is allowed to operate is: TA = TJ – (PDMAX • 190°C/W) TA = 150°C – (0.562W • 190°C/W) = 43°C For a higher operating temperature, lower the supply voltage or use the DIP package part. Input Offset Voltage The offset voltage changes depending upon which input stage is active, and the maximum offset voltages are trimmed to less than 1350µV. To maintain the precision characteristics of the amplifier, the change of VOS over the entire input common mode range (CMRR) is guaranteed to be less than 1500µV on a single 5V supply. Input Bias Current The input bias current polarity depends on the input common mode voltage. When the PNP differential pair is active, the input bias currents flow out of the input pins. LT1632/LT1633 APPLICATIONS INFORMATION They flow in the opposite direction when the NPN input stage is active. The offset voltage error due to input bias currents can be minimized by equalizing the noninverting and inverting input source impedance. Output The outputs of the LT1632/LT1633 can deliver large load currents; the short-circuit current limit is 70mA. Take care to keep the junction temperature of the IC below the absolute maximum rating of 150°C (refer to the Power Dissipation section). The output of these amplifiers have reverse-biased diodes to each supply. If the output is forced beyond either supply, unlimited current will flow through these diodes. If the current is transient and limited to several hundred mA, no damage to the part will occur. Overdrive Protection To prevent the output from reversing polarity when the input voltage exceeds the power supplies, two pairs of crossing diodes D1 to D4 are employed. When the input voltage exceeds either power supply by approximately 700mV, D1/D2 or D3/D4 will turn on, forcing the output to the proper polarity. For this phase reversal protection to work properly, the input current must be limited to less than 5mA. If the amplifier is to be severely overdriven, an external resistor should be used to limit the overdrive current. The LT1632/LT1633’s input stages are also protected against large differential input voltages by a pair of backto-back diodes D5/D8. When a differential voltage of more than 1.4V is applied to the inputs, these diodes will turn on, preventing the emitter-base breakdown of the input transistors. The current in D5/D8 should be limited to less than 10mA. Internal 225Ω resistors R6 and R7 will limit the input current for differential input signals of 4.5V or less. For larger input levels, a resistor in series with either or both inputs should be used to limit the current. Worst-case differential input voltage usually occurs when the output is shorted to ground. In addition, the amplifier is protected against ESD strikes up to 3kV on all pins. Capacitive Load The LT1632/LT1633 are wideband amplifiers that can drive capacitive loads up to 200pF on ± 15V supplies in a unity-gain configuration. On a 3V supply, the capacitive load should be kept to less than 100pF. When there is a need to drive larger capacitive loads, a resistor of 20Ω to 50Ω should be connected between the output and the capacitive load. The feedback should still be taken from the output so that the resistor isolates the capacitive load to ensure stability. Feedback Components The low input bias currents of the LT1632/LT1633 make it possible to use the high value feedback resistors to set the gain. However, care must be taken to ensure that the pole formed by the feedback resistors and the total capacitance at the inverting input does not degrade stability. For instance, the LT1632/LT1633 in a noninverting gain of 2, set with two 20k resistors, will probably oscillate with 10pF total input capacitance (5pF input capacitance and 5pF board capacitance). The amplifier has a 6MHz crossing frequency and a 55° phase margin at 6dB of gain. The feedback resistors and the total input capacitance form a pole at 1.6MHz that induces a phase shift of 75° at 5MHz! The solution is simple: either lower the value of the resistors or add a feedback capacitor of 10pF or more. TYPICAL APPLICATIONS Single Supply, 40dB Gain, 550kHz Instrumentation Amplifier An instrumentation amplifier with a rail-to-rail output swing, operating from a 3V supply can be constructed with the LT1632 as shown in the first page of this data sheet. The amplifier has a nominal gain of 100, which can be adjusted with resistor R5. The DC output level is set by the difference of the two inputs multiplied by the gain of 100. The voltage gain and the DC output level can be expressed as follows: U W U U U 13 LT1632/LT1633 TYPICAL APPLICATIONS R4  R2 R3 + R2  AV = + 1+ R3  R1 R5    − + VOUT =  VIN − VIN  • AV   10 0 –10 –20 GAIN (dB) –30 –40 –50 –60 –70 –80 VS = 3V, 0V VIN = 2.5VP-P 1k 10k 100k FREQUENCY (Hz) 1M 10M Common mode range can be calculated by the following equations: Lower limit common mode input voltage  V  R2  1.0 VCML =  OUT  + 0.1V    AV  R5  1.1 Upper limit common mode input voltage  V  R2  1.0 VCMH =  OUT  + VS − 0.15V   AV  R5  1.1   where VS is supply voltage. ( For example, the common mode range is from 0.15V to 2.65V if the output is set at one half of the 3V supply. The common mode rejection is greater than 110dB at 100Hz when trimmed with resistor R1. The amplifier has a bandwidth of 550kHz. Single Supply, 400kHz, 4th Order Butterworth Filter The circuit shown in Figure 2 makes use of the low voltage operation and the wide bandwidth of the LT1632 to create a 400kHz 4th order lowpass filter with a single supply. The amplifiers are configured in the inverting mode to minimize common mode induced distortion and the output can swing rail-to-rail for the maximum dynamic range. Figure 3 displays the frequency response of the filter. Stopband attenuation is greater than 85dB at 10MHz. C1 0.01µF + R3 10k L1 220µH C2 1500pF HP-MSA0785 VIN 2.32k 2.32k VIN 220pF 6.65k 47pF 2.74k 2.74k 5.62k 470pF 22pF L3 3.9µH 1/2 LT1632 1/2 LT1632 VOUT R5 50Ω VS/2 1632/33 F02 Figure 2. Single Supply, 400kHz, 4th Order Butterworth Filter Figure 4. RF Amplifier Control Biasing and DC Restoration 14 + – + – U –90 0.1k 1632/33 F03 Figure 3. Frequency Response ) With a 2.25VP-P, 100kHz input signal on a 3V supply, the filter has harmonic distortion of less than – 87dBc. RF Amplifier Control Biasing and DC Restoration Taking advantage of the rail-to-rail input and output, and the large output current capability of the LT1632, the circuit shown in Figure 4 provides precise bias current for the RF amplifiers and restores the DC output level. To ensure optimum performance of an RF amplifier, its bias point must be accurate and stable over the operating 5V R2 453Ω 5V R1 10Ω R4 10Ω A1 1/2 LT1632 Q1 2N3906 Q2 2N3906 + C5 0.01µF L2 220µH HP-MSA0785 + C6 0.01µF C3 1500pF C4 1500pF VOUT L4 3.9µH RF1 RF2 + – + A2 1/2 LT1632 1632/33 F04 – LT1632/LT1633 TYPICAL APPLICATIONS temperature range. The op amp A1 combined with Q1, Q2, R1, R2 and R3 establishes two current sources of 21.5mA to bias RF1 and RF2 amplifiers. The current of Q1, is determined by the voltage across R2 over R1, which is then replicated in Q2. These current sources are stable and precise over temperature and have a low dissipated power due to a low voltage drop between their terminals. The amplifier A2 is used to restore the DC level at the output. With a large output current of the LT1632, the output can be set at 1.5V DC on 5V supply and 50Ω load. This circuit has a – 3dB bandwidth from 2MHz to 2GHz and a power gain of 25dB. PACKAGE DESCRIPTION 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) 0.065 (1.651) TYP 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 ± 0.003 (0.457 ± 0.076) ( +0.035 0.325 –0.015 +0.889 8.255 –0.381 ) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 0.010 – 0.020 × 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 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) *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 U Dimensions in inches (millimeters) unless otherwise noted. N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.045 – 0.065 (1.143 – 1.651) 0.130 ± 0.005 (3.302 ± 0.127) 0.400* (10.160) MAX 8 7 6 5 0.255 ± 0.015* (6.477 ± 0.381) 1 2 3 4 N8 1197 0.100 ± 0.010 (2.540 ± 0.254) S8 Package 8-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.189 – 0.197* (4.801 – 5.004) 0.053 – 0.069 (1.346 – 1.752) 8 0.004 – 0.010 (0.101 – 0.254) 0.228 – 0.244 (5.791 – 6.197) 0.150 – 0.157** (3.810 – 3.988) 7 6 5 0.014 – 0.019 (0.355 – 0.483) 0.050 (1.270) TYP 1 2 3 4 SO8 0996 S Package 14-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.337 – 0.344* (8.560 – 8.738) 14 0.004 – 0.010 (0.101 – 0.254) 0.228 – 0.244 (5.791 – 6.197) 0.150 – 0.157** (3.810 – 3.988) 13 12 11 10 9 8 0.050 (1.270) TYP 1 2 3 4 5 6 7 S14 0695 15 LT1632/LT1633 TYPICAL APPLICATION Tunable Q Notch Filter A single supply, tunable Q notch filter as shown in Figure 5 is built with LT1632 to maximize the output swing. The filter has a gain of 2, and the notch frequency (fO) is set by the values of R and C. The resistors R10 and R11 set up the DC level at the output. The Q factor can be adjusted by varying the value of R8. The higher value of R8 will C 1000pF C1 2.2µF VIN R1 500Ω R 1.62k R 1.62k C 1000pF 5V 40 GAIN (VOUT/VIN)(dB) R2 1k 5V R10 10k C2 4.7µF R9 1k R11 10k A2 1/2 LT1632 R8 5k 1632/33 F05 Figure 5. Tunable Q Notch Filter RELATED PARTS PART NUMBER LT1211/LT1212 LT1213/LT1214 LT1215/LT1216 LT1498/LT1499 LT1630/LT1631 DESCRIPTON Dual/Quad 14MHz, 7V/µs, Single Supply Precision Op Amps Dual/Quad 28MHz, 12V/µs, Single Supply Precision Op Amps Dual/Quad 23MHz, 50V/µs, Single Supply Precision Op Amps Dual/Quad 10MHz, 6V/µs Rail-to-Rail Input and Output C-LoadTM Op Amps Dual/Quad 30MHz, 10V/µs Rail-to-Rail Input and Output Op Amps COMMENTS Input Common Mode Includes Ground, 275µV VOS(MAX), 6µV/°C Max Drift, Max Supply Current 1.8mA per Op Amp Input Common Mode Includes Ground, 275µV VOS(MAX), 6µV/°C Max Drift, Max Supply Current 3.5mA per Op Amp Input Common Mode Includes Ground, 450µV VOS(MAX), 6µV/°C Max Drift, Max Supply Current 6.6mA per Op Amp High DC Accuracy, 475µV VOS(MAX), 4µV/°C Max Drift, Max Supply Current 2.2mA per Amp High DC Accuracy, 525µV VOS(MAX), 70mA Output Current, Max Supply Current 4.4mA per Amp C-Load is a trademark of Linear Technology Corporation. 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 decrease Q as depicted in Figure 6, because the output induces less of feedback to amplifier A2. The value of R7 should be equal or greater than R9 to prevent oscillation. If R8 is a short and R9 is larger than R7, then the positive feedback from the output will create phase inversion at the output of amplifier A2, which will lead to oscillation. + A1 1/2 LT1632 VOUT 20 INCREASING R8 0 DECREASING R8 – R6 R5 1k 1k C5 4.7µF 1 2πRC R = 1.62k C = 1000pF fO = VO(DC) = 5V R7 1k AV = 2 R11 = 2.5V R11 + R10 –20 + – –40 0 20 40 60 80 100 120 140 160 180 200 FREQUENCY (kHz) 13632/33 F06 Figure 6. Frequency Response 16323f LT/TP 0998 4K • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1998