LT1361CN8#PBF

LT1361/LT1362 Dual and Quad 50MHz, 800V/µs Op Amps U DESCRIPTIO FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ 50MHz Gain Bandwidth 800V/µs Slew Rate 5mA Maximum Supply Current per Amplifier Unity-Gain Stable C-LoadTM Op Amp Drives All Capacitive Loads 9nV/√Hz Input Noise Voltage 1mV Maximum Input Offset Voltage 1µA Maximum Input Bias Current 250nA Maximum Input Offset Current ±13V Minimum Output Swing into 500Ω ±3.2V Minimum Output Swing into 150Ω 4.5V/mV Minimum DC Gain, RL=1k 60ns Settling Time to 0.1%, 10V Step 0.2% Differential Gain, AV=2, RL=150Ω 0.3° Differential Phase, AV=2, RL=150Ω Specified at ±2.5V, ±5V, and ±15V U APPLICATIO S ■ ■ ■ ■ ■ Wideband Amplifiers Buffers Active Filters Video and RF Amplification Cable Drivers Data Acquisition Systems The LT1361/LT1362 are members of a family of fast, high performance amplifiers using this unique topology and employing Linear Technology Corporation’s advanced bipolar complementary processing. For a single amplifier version of the LT1361/LT1362 see the LT1360 data sheet. For higher bandwidth devices with higher supply currents see the LT1363 through LT1365 data sheets. For lower supply current amplifiers see the LT1354 to LT1359 data sheets. Singles, duals, and quads of each amplifier are available. , LTC and LT are registered trademarks of Linear Technology Corporation. C-Load is a trademark of Linear Technology Corporation U ■ The LT1361/LT1362 are dual and quad low power high speed operational amplifiers with outstanding AC and DC performance. The amplifiers feature much lower supply current and higher slew rate than devices with comparable bandwidth. The circuit topology is a voltage feedback amplifier with matched high impedance inputs and the slewing performance of a current feedback amplifier. The high slew rate and single stage design provide excellent settling characteristics which make the circuit an ideal choice for data acquisition systems. Each output drives a 500Ω load to ±13V with ±15V supplies and a 150Ω load to ±3.2V on ±5V supplies. The amplifiers are stable with any capacitive load making them useful in buffer or cable driving applications. TYPICAL APPLICATIO Cable Driver Frequency Response AV = –1 Large-Signal Response 2 GAIN (dB) 0 VS = ±15V VS = ±10V VS = ±2.5V VS = ±5V –2 IN –4 –6 + 1/2 LT1361 – 510Ω 75Ω OUT 75Ω 510Ω –8 1 10 FREQUENCY (MHz) 100 1361/1362 TA02 1361/1362 TA01 1 LT1361/LT1362 W W U W ABSOLUTE MAXIMUM RATINGS (Note 1) Total Supply Voltage (V + to V –) ............................... 36V Differential Input Voltage (Transient Only) (Note 2)................................... ±10V Input Voltage ............................................................ ±VS Output Short-Circuit Duration (Note 3) ............ Indefinite Operating Temperature Range (Note 8) ...–40°C to 85°C Specified Temperature Range (Note 9) ....–40°C to 85°C Maximum Junction Temperature (See Below) Plastic Package ................................................ 150°C Storage Temperature Range ..................–65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C W U U PACKAGE/ORDER INFORMATION TOP VIEW OUT A 1 –IN A 2 8 V+ 7 OUT B A +IN A 3 V– 4 B 6 –IN B 5 +IN B ORDER PART NUMBER LT1361CN8 TOP VIEW OUT A 1 –IN A 2 8 V+ 7 OUT B 6 –IN B 5 +IN B +IN A 3 V– 4 B S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 130°C/ W TJMAX = 150°C, θJA = 190°C/ W OUT A 1 14 OUT D –IN A 2 13 –IN D +IN A 3 V+ 4 +IN B 5 –IN B 6 OUT B 7 A D 12 +IN D ORDER PART NUMBER LT1362CN 11 V – 10 +IN C B S8 PART MARKING 1361 ORDER PART NUMBER TOP VIEW OUT A 1 –IN A 2 +IN A 3 V+ 4 +IN B 5 16 OUT D 15 –IN D A D LT1362CS 14 +IN D 13 V – 12 +IN C C B C 9 –IN C –IN B 6 8 OUT C OUT B 7 10 OUT C NC 8 9 N PACKAGE 14-LEAD PDIP LT1361CS8 A N8 PACKAGE 8-LEAD PDIP TOP VIEW ORDER PART NUMBER 11 –IN C NC S PACKAGE 16-LEAD PLASTIC SO TJMAX = 150°C, θJA = 110°C/ W TJMAX = 150°C, θJA = 150°C/ W Consult factory for Industrial and Military grade parts. ELECTRICAL CHARACTERISTICS TA = 25°C, VCM = 0V unless otherwise noted. SYMBOL PARAMETER CONDITIONS VSUPPLY VOS Input Offset Voltage (Note 4) IOS Input Offset Current IB Input Bias Current en Input Noise Voltage f = 10kHz in Input Noise Current f = 10kHz ±2.5V to ±15V RIN Input Resistance VCM = ±12V ±15V Input Resistance Differential CIN 2 Input Capacitance MIN TYP MAX UNITS ±15V ±5V ±2.5V 0.3 0.3 0.4 1.0 1.0 1.2 mV mV mV ±2.5V to ±15V 80 250 nA ±2.5V to ±15V 0.3 1.0 ±2.5V to ±15V 9 nV/√Hz 0.9 pA/√Hz 50 MΩ ±15V 5 MΩ ±15V 3 pF 20 µA LT1361/LT1362 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER TA = 25°C, VCM = 0V unless otherwise noted. VSUPPLY MIN TYP + ±15V ±5V ±2.5V 12.0 2.5 0.5 13.4 3.4 1.1 Input Voltage Range – ±15V ±5V ±2.5V Input Voltage Range CONDITIONS CMRR Common Mode Rejection Ratio VCM = ±12V VCM = ±2.5V VCM = ±0.5V PSRR Power Supply Rejection Ratio VS = ±2.5V to ±15V AVOL Large-Signal Voltage Gain VOUT = ±12V, RL = 1k VOUT = ±10V, RL = 500Ω VOUT = ±2.5V, RL = 500Ω VOUT = ±2.5V, RL = 150Ω VOUT = ±1V, RL = 500Ω VOUT Output Swing IOUT Output Current ±15V ±5V ±2.5V –13.2 –3.2 –0.9 MAX UNITS V V V –12.0 –2.5 –0.5 V V V 86 79 68 92 84 74 dB dB dB 93 105 dB ±15V ±15V ±5V ±5V ±2.5V 4.5 3.0 3.0 1.5 2.5 9.0 6.5 6.4 4.2 5.2 V/mV V/mV V/mV V/mV V/mV RL = 1k, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 150Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV ±15V ±15V ±5V ±5V ±2.5V 13.5 13.0 3.5 3.2 1.3 13.9 13.6 4.0 3.8 1.7 ±V ±V ±V ±V ±V VOUT = ±13V VOUT = ±3.2V ±15V ±5V 26 21 34 29 mA mA ISC Short-Circuit Current VOUT = 0V, VIN = ±3V ±15V 40 54 mA SR Slew Rate AV = – 2, (Note 5) ±15V ±5V 600 250 800 350 V/µs V/µs Full Power Bandwidth 10V Peak, (Note 6) 3V Peak, (Note 6) ±15V ±5V 12.7 18.6 MHz MHz GBW Gain Bandwidth f = 200kHz ±15V ±5V ±2.5V 50 37 32 MHz MHz MHz tr, tf Rise Time, Fall Time AV = 1, 10%-90%, 0.1V ±15V ±5V 3.1 4.3 ns ns Overshoot AV = 1, 0.1V ±15V ±5V 35 27 % % Propagation Delay 50% VIN to 50% VOUT, 0.1V ±15V ±5V 5.2 6.4 ns ns Settling Time 10V Step, 0.1%, AV = –1 10V Step, 0.01%, AV = –1 5V Step, 0.1%, AV = –1 ±15V ±15V ±5V 60 90 65 ns ns ns Differential Gain f = 3.58MHz, AV = 2, RL = 150Ω ±15V ±5V ±15V ±5V 0.20 0.20 0.04 0.02 % % % % ±15V ±5V ±15V ±5V 0.40 0.30 0.07 0.26 Deg Deg Deg Deg ts f = 3.58MHz, AV = 2, RL = 1k Differential Phase f = 3.58MHz, AV = 2, RL = 150Ω f = 3.58MHz, AV = 2, RL = 1k RO IS Output Resistance AV = 1, f = 1MHz ±15V Channel Separation VOUT = ±10V, RL = 500Ω ±15V Supply Current Each Amplifier Each Amplifier ±15V ±5V 35 25 100 1.4 Ω 113 dB 4.0 3.8 5.0 4.8 mA mA 3 LT1361/LT1362 ELECTRICAL CHARACTERISTICS 0°C ≤ TA ≤ 70°C, VCM = 0V unless otherwise noted. The ● denotes the specifications which apply over the temperature range SYMBOL PARAMETER CONDITIONS VSUPPLY VOS Input Offset Voltage (Note 4) ±15V ±5V ±2.5V ● ● ● MIN Input VOS Drift (Note 7) ±2.5V to ±15V ● TYP 9 MAX UNITS 1.5 1.5 1.7 mV mV mV 12 µV/°C IOS Input Offset Current ±2.5V to ±15V ● 350 nA IB Input Bias Current ±2.5V to ±15V ● 1.5 µA CMRR Common Mode Rejection Ratio ±15V ±5V ±2.5V ● ● ● PSRR Power Supply Rejection Ratio VS = ±2.5V to ±15V ● 91 dB AVOL Large-Signal Voltage Gain VOUT = ±12V, RL = 1k VOUT = ±10V, RL = 500Ω VOUT = ±2.5V, RL = 500Ω VOUT = ±2.5V, RL = 150Ω VOUT = ±1V, RL = 500Ω ±15V ±15V ±5V ±5V ±2.5V ● ● ● ● ● 3.6 2.4 2.4 1.0 2.0 V/mV V/mV V/mV V/mV V/mV VOUT Output Swing RL = 1k, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 150Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV ±15V ±15V ±5V ±5V ±2.5V ● ● ● ● ● 13.4 12.8 3.4 3.1 1.2 ±V ±V ±V ±V ±V IOUT Output Current VOUT = ±12.8V VOUT = ±3.1V ±15V ±5V ● ● 25 20 mA mA VCM = ±12V VCM = ±2.5V VCM = ±0.5V 84 77 66 dB dB dB ISC Short-Circuit Current VOUT = 0V, VIN = ±3V ±15V ● 32 mA SR Slew Rate AV = – 2, (Note 5) ±15V ±5V ● ● 475 185 V/µs V/µs GBW Gain Bandwidth f = 200kHz ±15V ±5V ● ● 31 22 MHz MHz Channel Separation VOUT = ±10V, RL = 500Ω ±15V ● 98 Supply Current Each Amplifier Each Amplifier ±15V ±5V ● ● IS dB 5.8 5.6 mA mA The ● denotes the specifications which apply over the temperature range – 40°C ≤ TA ≤ 85°C, VCM = 0V unless otherwise noted. (Note 9) SYMBOL PARAMETER CONDITIONS VSUPPLY VOS Input Offset Voltage (Note 4) ±15V ±5V ±2.5V ● ● ● Input VOS Drift (Note 7) ±2.5V to ±15V ● ±2.5V to ±15V ● ±2.5V to ±15V ● ±15V ±5V ±2.5V ● ● ● 84 77 66 dB dB dB ● 90 dB ● ● ● ● ● 2.5 1.5 1.5 0.6 1.3 V/mV V/mV V/mV V/mV V/mV IOS Input Offset Current IB Input Bias Current CMRR Common Mode Rejection Ratio VCM = ±12V VCM = ±2.5V VCM = ±0.5V PSRR Power Supply Rejection Ratio VS = ±2.5V to ±15V AVOL Large-Signal Voltage Gain VOUT = ±12V, RL = 1k VOUT = ±10V, RL = 500Ω VOUT = ±2.5V, RL = 500Ω VOUT = ±2.5V, RL = 150Ω VOUT = ±1V, RL = 500Ω 4 ±15V ±15V ±5V ±5V ±2.5V MIN TYP 9 MAX UNITS 2.0 2.0 2.2 mV mV mV 12 µV/°C 400 nA 1.8 µA LT1361/LT1362 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the temperature range – 40°C ≤ TA ≤ 85°C, VCM = 0V unless otherwise noted. (Note 9) SYMBOL PARAMETER CONDITIONS VSUPPLY VOUT Output Swing RL = 1k, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV RL = 150Ω, VIN = ±40mV RL = 500Ω, VIN = ±40mV ±15V ±15V ±5V ±5V ±2.5V ● ● ● ● ● 13.4 12.0 3.4 3.0 1.2 ±V ±V ±V ±V ±V IOUT Output Current VOUT = ±12.0V VOUT = ±3.0V ±15V ±5V ● ● 24 20 mA mA ISC Short-Circuit Current VOUT = 0V, VIN = ±3V ±15V ● 30 mA SR Slew Rate AV = – 2, (Note 5) ±15V ±5V ● ● 450 175 V/µs V/µs GBW Gain Bandwidth f = 200kHz ±15V ±5V ● ● 30 20 MHz MHz Channel Separation VOUT = ±10V, RL = 500Ω ±15V ● 98 dB Supply Current Each Amplifier Each Amplifier ±15V ±5V ● ● IS Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Differential inputs of ±10V are appropriate for transient operation only, such as during slewing. Large, sustained differential inputs will cause excessive power dissipation and may damage the part. See Input Considerations in the Applications Information section of this data sheet for more details. Note 3: A heat sink may be required to keep the junction temperature below absolute maximum when the output is shorted indefinitely. Note 4: Input offset voltage is pulse tested and is exclusive of warm-up drift. Note 5: Slew rate is measured between ±10V on the output with ±6V input for ±15V supplies and ±1V on the output with ±1.75V input for ±5V supplies. MIN TYP MAX UNITS 6.0 5.8 mA mA Note 6: Full power bandwidth is calculated from the slew rate measurement: FPBW = SR/2πVP. Note 7: This parameter is not 100% tested. Note 8: The LT1361C/LT1362C are guaranteed functional over the operating temperature range of –40°C to 85°C. Note 9: The LT1361C/LT1362C are guaranteed to meet specified performance from 0°C to 70°C. The LT1361C/LT1362C 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. For guaranteed I-grade parts, consult the factory. U W TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Supply Voltage and Temperature V+ 6 0.6 TA = 25°C ∆VOS < 1mV –0.5 125°C 4 25°C 3 – 55°C 2 0.5 –1.0 INPUT BIAS CURRENT (µA) COMMON MODE RANGE (V) 5 SUPPLY CURRENT (mA) Input Bias Current vs Input Common Mode Voltage Input Common Mode Range vs Supply Voltage –1.5 –2.0 2.0 1.5 1.0 VS = ±15V TA = 25°C IB+ + IB– IB = ———— 2   0.4 0.3 0.2 0.1 0.5 1 0 5 10 15 SUPPLY VOLTAGE (±V) 20 1361/1362 G01 V– 0 5 10 15 SUPPLY VOLTAGE (±V) 20 1361/1362 G02 0 –15 –10 –5 0 5 10 INPUT COMMON MODE VOLTAGE (V) 15 1361/1362 G03 5 LT1361/LT1362 U W TYPICAL PERFORMANCE CHARACTERISTICS Input Bias Current vs Temperature 0.4 0.3 0.2 0.1 0 –50 en in 10 1 1 –25 0 25 50 75 TEMPERATURE (°C) 100 10 125 100 10 77 76 75 74 Output Voltage Swing vs Load Current –2 RL = 500Ω –3 3 RL = 500Ω 2 0 25 50 75 TEMPERATURE (°C) 100 RL = 1k 0 125 5 10 15 SUPPLY VOLTAGE (±V) 20 Output Short-Circuit Current vs Temperature 6 SINK 45 1.0 85°C 0.5 V– –50 –40 –30 –20 –10 0 10 20 30 40 50 OUTPUT CURRENT (mA) VS = ±15V AV = –1 RF = 1k CF = 3pF 8 10mV 6 1mV 4 2 0 –2 –4 4 40 1mV 0 –2 –4 10mV –6 1mV –8 0 25 50 75 TEMPERATURE (°C) 100 125 1361/1362 G10 1mV –8 –10 –25 10mV 2 10mV –6 35 –50 25°C 1.5 Settling Time vs Output Step (Inverting) OUTPUT STEP (V) OUTPUT STEP (V) SOURCE –40°C 2.0 10 VS = ±15V AV = 1 RL = 1k 8 65 50 –40°C –2.0 1361/1362 G09 10 VS = ±5V 55 25°C –1.5 Settling Time vs Output Step (Noninverting) 60 85°C –1.0 1361/1362 G08 1361/1362 G07 70 VS = ±5V VIN = 100mV –0.5 V– –25 10k 1361/1362 G06 RL = 1k 1 73 72 – 50 100 1k LOAD RESISTANCE (Ω) V+ –1 OUTPUT VOLTAGE SWING (V) OPEN-LOOP GAIN (dB) 60 TA = 25°C 78 6 65 V+ 79 70 Output Voltage Swing vs Supply Voltage 81 80 VS = ±5V 75 1361/1362 G05 Open-Loop Gain vs Temperature VS = ±15V VO = ±12V RL = 1k VS = ±15V 80 0.1 100k 1k 10k FREQUENCY (Hz) 1361/1362 G04 OUTPUT SHORT-CIRCUIT CURRENT (mA) TA = 25°C OPEN-LOOP GAIN (dB) 0.5 85 OUTPUT VOLTAGE SWING (V) INPUT BIAS CURRENT (µA)  VS = ±15V TA = 25°C AV = 101 RS = 100k INPUT CURRENT NOISE (pA/√Hz)  0.6 10 100 VS = ±15V IB+ + IB– IB = ———— 2 INPUT VOLTAGE NOISE (nV/√Hz) 0.7 Open-Loop Gain vs Resistive Load Input Noise Spectral Density –10 0 20 40 60 80 SETTLING TIME (ns) 100 1361/1362 G11 0 20 40 60 80 SETTLING TIME (ns) 100 1361/1362 G12 LT1361/LT1362 U W TYPICAL PERFORMANCE CHARACTERISTICS Output Impedance vs Frequency Gain and Phase vs Frequency AV = 1 1 40 VS = ±5V 40 VS = ±5V 20 20 10 1M 10M FREQUENCY (Hz) 100M –10 10k 100k 1M 10M FREQUENCY (Hz) 45 4 40 3 30 60 25 GAIN BANDWIDTH VS = ±15V 20 15 GAIN BANDWIDTH VS = ±5V 30 –50 –25 0 25 50 75 TEMPERATURE (°C) 100 12 ±15V 1 0 –1 10 –3 5 –4 ±5V 1M 10M FREQUENCY (Hz) 50 42 40 38 36 40 34 GAIN BANDWIDTH 32 30 30 0 5 10 15 SUPPLY VOLTAGE (±V) 20 POWER SUPPLY REJECTION RATIO (dB) 44 PHASE MARGIN (DEG) GAIN BANDWIDTH (MHz) 46 50 C = 50pF 2 0 C=0 –2 –4 –8 1M 100M Common Mode Rejection Ratio vs Frequency 120 +PSRR 80 – PSRR VS = ±15V TA = 25°C 60 40 20 0 100 100M 10M FREQUENCY (Hz) 1361/1362 G18 100 48 60 C = 100pF 4 Power Supply Rejection Ratio vs Frequency PHASE MARGIN C = 500pF 6 1361/1362 G17 Gain Bandwidth and Phase Margin vs Supply Voltage 70 8 C = 1000pF –6 ±2.5V –5 100k VS = ±15V TA = 25°C AV = –1 10 1361/1362 G16 TA = 25°C 100M 1361/1362 G21 TA = 25°C AV = 1 RL = 1k –2 0 125 80 1M 10M FREQUENCY (Hz) Frequency Response vs Capacitive Load 2 GAIN (dB) 35 PHASE MARGIN (DEG) PHASE MARGIN VS = ±15V VS = ±5V RL = 500Ω –120 100k 100M 5 50 70 VS = ±15V RL = 1k –90 Frequency Response vs Supply Voltage (AV = 1) PHASE MARGIN VS = ±5V 40 –70 –80 1361/1362 G14 Gain Bandwidth and Phase Margin vs Temperature 50 –60 –110 1361/1362 G13 80 –50 –100 VOLTAGE MAGNITUDE (dB) 100k 0 TA = 25°C AV = –1 RF = RG = 1k 0 TA = 25°C AV = 1 VIN = 0dBm –40 COMMON-MODE REJECTION RATIO (dB) 0.01 10k –30 60 30 0.1 100 80 VS = ±15V GAIN –20 CROSSTALK (dB) 50 GAIN (dB) OUTPUT IMPEDANCE (Ω) VS = ±15V 120 PHASE (DEG) AV = 100 10 PHASE 60 AV = 10 VS = ±15V TA = 25°C GAIN BANDWIDTH (MHz) Crosstalk vs Frequency 70 100 VS = ±15V TA = 25°C 100 80 60 40 20 0 1k 10k 100k 1M FREQUENCY (Hz) 10M 100M 1361/1362 G19 1k 10k 100k 1M FREQUENCY (Hz) 10M 100M 1361/1362 G20 1361/1362 G15 7 LT1361/LT1362 U W TYPICAL PERFORMANCE CHARACTERISTICS Slew Rate vs Temperature Slew Rate vs Supply Voltage TA = 25°C AV = –1 RF = RG = 1k SR+ + SR – SR = ————— 2 800 1200 1000 800 600 700 VS = ±15V 600 500 0 0 5 10 SUPPLY VOLTAGE (±V) 15 400 0 –25 0 25 50 75 TEMPERATURE (°C) 100 0 125 1k 10k FREQUENCY (Hz) AV = 1 15 10 VS = ±15V RL = 1k AV = 1, 1% MAX DISTORTION AV = –1, 2% MAX DISTORTION 0 100k 100k OUTPUT VOLTAGE (VP-P) OUTPUT VOLTAGE (VP-P) 0.0001 1M FREQUENCY (Hz) 1361/1362 G25 3RD HARMONIC DIFFERENTIAL GAIN DIFFERENTIAL PHASE (DEG) –50 –80 400k 1M 2M FREQUENCY (Hz) 4M 10M 1361/1362 G28 VS = ±5V RL = 1k 2% MAX DISTORTION 1M FREQUENCY (Hz) 10M 0 0.40 0.36 DIFFERENTIAL PHASE 0.32 0.28 1361/1362 G27 DIFFERENTIAL GAIN (%) Differential Gain and Phase vs Supply Voltage 0.25 2ND HARMONIC 4 0 100k 10M 0.50 –70 AV = 1 6 2 –30 –60 AV = –1 8 1361/1362 G26 2nd and 3rd Harmonic Distortion vs Frequency 20 10 20 5 –90 100k 200k 6 8 10 12 14 16 18 INPUT LEVEL (VP-P) Undistorted Output Swing vs Frequency (±5V) 25 AV = 1 VS = ±15V VO = 2VP-P RL = 500Ω AV = 2 4 AV = –1 AV = –1 100 2 1361/1362 G24 30 TA = 25°C VO = 3VRMS RL = 500Ω 10 600 Undistorted Output Swing vs Frequency (±15V) 0.01 0.001 800 1361/1362 G23 Total Harmonic Distortion vs Frequency HARMONIC DISTORTION (dB) 1000 200 200 –50 1361/1362 G22 8 1200 300 200 –40 1400 VS = ± 5V 400 400 1600 SLEW RATE (V/µs) 1400 TA = 25°C VS = ±15V AV = –1 RF = RG = 1k SR + + SR – SR = ————— 2 1800 SR + + SR – SR = ————— 2 Capacitive Load Handling 100 TA = 25°C VS = ±15V OVERSHOOT (%) SLEW RATE (V/µs) 1600 AV = –2 900 SLEW RATE (V/µs) 1800 TOTAL HARMONIC DISTORTION (%) Slew Rate vs Input Level 2000 1000 2000 AV = –1 50 AV = 2 RL = 150Ω TA = 25°C ±5 ±10 SUPPLY VOLTAGE (V) AV = 1 ±15 1361/1362 G29 0 10p 100p 1000p 0.01µ 0.1µ CAPACITIVE LOAD (F) 1µ 1361/1362 G30 LT1361/LT1362 U W TYPICAL PERFORMANCE CHARACTERISTICS Small-Signal Transient (AV = 1) Small-Signal Transient (AV = –1) 1361/1362 TA31 Small-Signal Transient (AV = –1, CL = 500pF) 1361/1362 TA33 1361/1362 TA32 Large-Signal Transient (AV = 1) Large-Signal Transient (AV = –1) 1361/1362 TA34 Large-Signal Transient (AV = 1, CL = 10,000pF) 1361/1362 TA35 1361/1362 TA36 U W U U APPLICATIONS INFORMATION Layout and Passive Components Input Considerations The LT1361/LT1362 amplifiers are easy to use and tolerant of less than ideal layouts. For maximum performance (for example, fast 0.01% settling) use a ground plane, short lead lengths, and RF-quality bypass capacitors (0.01µF to 0.1µF). For high drive current applications use low ESR bypass capacitors (1µF to 10µF tantalum). The parallel combination of the feedback resistor and gain setting resistor on the inverting input combine with the input capacitance to form a pole which can cause peaking or oscillations. If feedback resistors greater than 5kΩ are used, a parallel capacitor of value Each of the LT1361/LT1362 inputs is the base of an NPN and a PNP transistor whose base currents are of opposite polarity and provide first-order bias current cancellation. Because of variation in the matching of NPN and PNP beta, the polarity of the input bias current can be positive or negative. The offset current does not depend on NPN/PNP beta matching and is well controlled. The use of balanced source resistance at each input is recommended for applications where DC accuracy must be maximized. CF > RG x CIN/RF should be used to cancel the input pole and optimize dynamic performance. For unity-gain applications where a large feedback resistor is used, CF should be greater than or equal to CIN. The inputs can withstand transient differential input voltages up to 10V without damage and need no clamping or source resistance for protection. Differential inputs, however, generate large supply currents (tens of mA) as required for high slew rates. If the device is used with sustained differential inputs, the average supply current will increase, excessive power dissipation will result and the part may be damaged. The part should not be used as a comparator, peak detector or other open-loop applica- 9 LT1361/LT1362 U W U U APPLICATIONS INFORMATION tion with large, sustained differential inputs. Under normal, closed-loop operation, an increase of power dissipation is only noticeable in applications with large slewing outputs and is proportional to the magnitude of the differential input voltage and the percent of the time that the inputs are apart. Measure the average supply current for the application in order to calculate the power dissipation. Capacitive Loading The LT1361/LT1362 are stable with any capacitive load. This is accomplished by sensing the load induced output pole and adding compensation at the amplifier gain node. As the capacitive load increases, both the bandwidth and phase margin decrease so there will be peaking in the frequency domain and in the transient response as shown in the typical performance curves. The photo of the small signal response with 500pF load shows 60% peaking. The large signal response shows the output slew rate being limited to 5V/µs by the short-circuit current. Coaxial cable can be driven directly, but for best pulse fidelity a resistor of value equal to the characteristic impedance of the cable (i.e., 75Ω) should be placed in series with the output. The other end of the cable should be terminated with the same value resistor to ground. Circuit Operation The LT1361/LT1362 circuit topology is a true voltage feedback amplifier that has the slewing behavior of a current feedback amplifier. The operation of the circuit can be understood by referring to the simplified schematic. The inputs are buffered by complementary NPN and PNP emitter followers which drive a 500Ω resistor. The input voltage appears across the resistor generating currents which are mirrored into the high impedance node. Complementary followers form an output stage which buffers the gain node from the load. The bandwidth is set by the input resistor and the capacitance on the high impedance node. The slew rate is determined by the current available to charge the gain node capacitance. This current is the differential input voltage divided by R1, so the slew rate is proportional to the input. Highest slew rates are therefore seen in the lowest gain configurations. For example, a 10V output step in a gain of 10 has only a 1V input step, 10 whereas the same output step in unity gain has a 10 times greater input step. The curve of Slew Rate vs Input Level illustrates this relationship. The LT1361/LT1362 are tested for slew rate in a gain of –2 so higher slew rates can be expected in gains of 1 and –1, and lower slew rates in higher gain configurations. The RC network across the output stage is bootstrapped when the amplifier is driving a light or moderate load and has no effect under normal operation. When driving a capacitive load (or a low value resistive load) the network is incompletely bootstrapped and adds to the compensation at the high impedance node. The added capacitance slows down the amplifier which improves the phase margin by moving the unity-gain frequency away from the pole formed by the output impedance and the capacitive load. The zero created by the RC combination adds phase to ensure that even for very large load capacitances, the total phase lag can never exceed 180 degrees (zero phase margin) and the amplifier remains stable. Power Dissipation The LT1361/LT1362 combine high speed and large output drive in small packages. Because of the wide supply voltage range, it is possible to exceed the maximum junction temperature under certain conditions. Maximum junction temperature (TJ) is calculated from the ambient temperature (TA) and power dissipation (PD) as follows: LT1361CN8: LT1361CS8: LT1362CN: LT1362CS: TJ = TA + (PD x 130°C/W) TJ = TA + (PD x 190°C/W) TJ = TA + (PD x 110°C/W) TJ = TA + (PD x 150°C/W) Worst case power dissipation occurs at the maximum supply current and when the output voltage is at 1/2 of either supply voltage (or the maximum swing if less than 1/2 supply voltage). For each amplifier PDMAX is: PDMAX = (V+ – V–)(ISMAX) + (V+/2)2/RL Example: LT1362 in S16 at 70°C, VS = ±5V, RL = 100Ω PDMAX = (10V)(5.6mA) + (2.5V)2/100Ω = 119mW TJMAX = 70°C + (4 x 119mW)(150°C/W) = 141°C LT1361/LT1362 W W SI PLIFIED SCHE ATIC V+ R1 500Ω +IN CC RC OUT –IN C V– 1361/1362 SS01 U PACKAGE DESCRIPTION Dimension in inches (millimeters) unless otherwise noted. N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.300 – 0.325 (7.620 – 8.255) 0.045 – 0.065 (1.143 – 1.651) ( +0.035 0.325 –0.015 +0.889 8.255 –0.381 0.130 ± 0.005 (3.302 ± 0.127) 0.065 (1.651) TYP 0.009 – 0.015 (0.229 – 0.381) ) 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 0.100 (2.54) BSC (0.457 ± 0.076) N8 1098 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) N Package 14-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.130 ± 0.005 (3.302 ± 0.127) 0.300 – 0.325 (7.620 – 8.255) 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 ) 0.770* (19.558) MAX 0.045 – 0.065 (1.143 – 1.651) 0.125 (3.175) MIN 0.018 ± 0.003 (0.457 ± 0.076) 14 13 12 11 10 9 8 1 2 3 4 5 6 7 0.255 ± 0.015* (6.477 ± 0.381) 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. N14 1098 11 LT1361/LT1362 U TYPICAL APPLICATIONS Two Op Amp Instrumentation Amplifier R5 220Ω R1 10k 1MHz, 4th Order Butterworth Filter R4 10k 909Ω R2 1k 22pF 909Ω R3 1k – 1/2 LT1361 2.67k VIN – 220pF 1/2 LT1361 + – 1.1k 47pF – 1.1k 1/2 LT1361 2.21k + VOUT – 1/2 LT1361 470pF + (  R4    1   R2 R3  R2 + R3 GAIN =   1 +    + + R5  R3    2   R1 R4   VOUT + + VIN 1361/1362 TA04 )  = 102   TRIM R5 FOR GAIN TRIM R1 FOR COMMON-MODE REJECTION BW = 500kHz 1361/1362 TA03 U PACKAGE DESCRIPTION Dimension 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) 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 7 8 5 6 0.004 – 0.010 (0.101 – 0.254) 0.150 – 0.157** (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) 0.050 (1.270) BSC 1 3 2 4 SO8 1298 S Package 16-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.386 – 0.394* (9.804 – 10.008) 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) 0.004 – 0.010 (0.101 – 0.254) 16 15 14 13 12 11 10 9 0° – 8° TYP 0.014 – 0.019 0.016 – 0.050 (0.355 – 0.483) (0.406 – 1.270) 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 0.228 – 0.244 (5.791 – 6.197) 0.050 (1.270) BSC 0.150 – 0.157** (3.810 – 3.988) 1 2 3 4 5 6 7 8 S16 1098 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1360 50MHz, 800V/µs Op Amp Single Version of LT1361/LT1362 LT1364/LT1365 Dual and Quad 70MHz, 1000V/µs Op Amps Faster Version of LT1361/LT1362, VOS = 1.5mV, IS = 6.3mA/Amplifier LT1358/LT1359 Dual and Quad 25MHz, 600Vµs Op Amps Lower Power Version of LT1361/LT1362, VOS = 0.6mV, IS = 2mA/Amplifier LT1813 Dual 100MHz, 700V/µs Op Amps Low Voltage, Low Power LT1361, IS = 3mA/Amplifier 12 Linear Technology Corporation 13612fa LT/TP 0400 2K REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com  LINEAR TECHNOLOGY CORPORATION 1994