LT1812IS8

LT1812 3mA, 100MHz, 750V/µs Operational Amplifier with Shutdown FEATURES s s s s s s s s s s s s s s s DESCRIPTIO 100MHz Gain Bandwidth 750V/µs Slew Rate 3.6mA Maximum Supply Current Available in SOT-23 and S8 Packages 50µA Supply Current in Shutdown 8nV/√Hz Input Noise Voltage Unity-Gain Stable 1.5mV Maximum Input Offset Voltage 4µA Maximum Input Bias Current 400nA Maximum Input Offset Current 40mA Minimum Output Current, VOUT = ± 3V ± 3.5V Minimum Input CMR, VS = ± 5V 30ns Settling Time to 0.1%, 5V Step Specified at ± 5V, Single 5V Supplies Operating Temperature Range: – 40°C to 85°C The LT®1812 is a low power, high speed, very high slew rate operational amplifier with excellent DC performance. The LT1812 features reduced supply current, lower input offset voltage, lower input bias current and higher DC gain than other devices with comparable bandwidth. A power saving shutdown feature reduces supply current to 50µA. The circuit topology is a voltage feedback amplifier with the slewing characteristics of a current feedback amplifier. The output drives a 100Ω load to ± 3.5V with ± 5V supplies. On a single 5V supply, the output swings from 1.1V to 3.9V with a 100Ω load connected to 2.5V. The amplifier is stable with a 1000pF capacitive load which makes it useful in buffer and cable driver applications. The LT1812 is manufactured on Linear Technology’s advanced low voltage complementary bipolar process. The dual version is the LT1813. For higher supply voltage single, dual and quad operational amplifiers with up to 70MHz gain bandwidth, see the LT1351 through LT1365 data sheets. APPLICATIO S s s s s s s Wideband Amplifiers Buffers Active Filters Video and RF Amplification Cable Drivers Data Acquisition Systems , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO 4MHz, 4th Order Butterworth Filter 232Ω 274Ω 232Ω VIN 220pF 665Ω 47pF VOLTAGE GAIN (dB) 10 0 –10 –20 –30 –40 –50 –60 –70 –80 1812 TA01 LT1812 470pF + – 274Ω 562Ω 22pF LT1812 VOUT –90 0.1 U Filter Frequency Response VS = ± 5V VIN = 600mVP-P PEAKING < 0.12dB 1 10 FREQUENCY (MHz) 100 1812 TA02 U U + – 1 LT1812 ABSOLUTE AXI U RATI GS Total Supply Voltage (V + to V –) ............................. 12.6V Differential Input Voltage (Transient Only, Note 2) ... ± 3V Input Voltage, Shutdown Voltage ............................. ±VS Output Short-Circuit Duration (Note 3) ............ Indefinite Operating Temperature Range (Note 8) ... – 40°C to 85°C PACKAGE/ORDER I FOR ATIO ORDER PART NUMBER TOP VIEW VOUT 1 V– 2 +IN 3 + – 4 –IN 5 V+ TOP VIEW LT1812CS5 LT1812IS5 S5 PART MARKING LTLH LTLJ VOUT 1 V– 2 +IN 3 + – S5 PACKAGE 5-LEAD PLASTIC SOT-23 S6 PACKAGE 6-LEAD PLASTIC SOT-23 TJMAX = 150°C, θJA = 250°C/ W (NOTE 9) TJMAX = 150°C, θJA = 230°C/ W (NOTE 9) Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS SYMBOL VOS IOS IB en in RIN CIN VCM CMRR PSRR AVOL VOUT IOUT ISC SR PARAMETER Input Offset Voltage Input Offset Current Input Bias Current Input Noise Voltage Density Input Noise Current Density Input Resistance Input Capacitance Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Minimum Supply Voltage Power Supply Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing Maximum Output Current Output Short-Circuit Current Slew Rate (Note 4) TA = 25°C, VS = ± 5V, VCM = 0V unless otherwise noted (Note 10). MIN TYP 0.4 30 – 0.9 MAX 1.5 400 ±4 UNITS mV nA µA nV/√Hz pA/√Hz MΩ MΩ pF – 3.5 ±2 V V dB V dB V/mV V/mV V V mA mA V/µs CONDITIONS f = 10kHz f = 10kHz VCM = ± 3.5V Differential 3 VCM = ± 3.5V VS = ± 2V to ± 5.5V VOUT = ± 3V, RL = 500Ω VOUT = ± 3V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = ± 3V, 30mV Overdrive VOUT = 0V, 1V Overdrive (Note 3) AV = – 1 (Note 5) 2 U U W WW U W (Note 1) Specified Temperature Range (Note 8) .............................................. – 40°C to 85°C Maximum Junction Temperature ......................... 150°C Storage Temperature Range .................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................... 300°C ORDER PART NUMBER 6 V+ 5 SHDN 4 –IN TOP VIEW NC 1 –IN 2 +IN 3 V– 4 – + 8 7 6 5 SHDN V+ VOUT NC ORDER PART NUMBER LT1812CS8 LT1812IS8 S8 PART MARKING 1812 1812I LT1812CS6 LT1812IS6 S6 PART MARKING LTLK LTLL S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 150°C/ W (NOTE 9) 8 1 10 1.5 2 3.5 75 78 1.5 1.0 ± 3.80 ± 3.35 ± 40 ± 75 500 4.2 – 4.2 85 ±1.25 97 3.0 2.5 ± 4.0 ± 3.5 ± 60 ± 110 750 LT1812 ELECTRICAL CHARACTERISTICS SYMBOL FPBW GBW tr, tf OS tPD ts THD PARAMETER Full Power Bandwidth Gain Bandwidth Product Rise Time, Fall Time Overshoot Propagation Delay Settling Time Total Harmonic Distortion Differential Gain Differential Phase ROUT ISHDN IS Output Resistance SHDN Pin Current Supply Current TA = 25°C, VS = ± 5V, VCM = 0V unless otherwise noted (Note 10). MIN 75 TYP 40 100 2 25 2.8 30 –76 0.12 0.07 0.4 –100 0 – 50 3 50 ±1 3.6 100 MAX UNITS MHz MHz ns % ns ns dB % DEG Ω µA µA mA µA CONDITIONS 3V Peak (Note 6) f = 200kHz AV = 1, 10% to 90%, 0.1V, RL = 100Ω AV = 1, 0.1V, RL = 100Ω AV = 1, 50% VIN to 50% VOUT, 0.1V, RL = 100Ω 5V Step, 0.1%, AV = – 1 f = 1MHz, VOUT = 2VP-P, AV = 2, RL = 500Ω VOUT = 2VP-P, AV = 2, RL = 150Ω VOUT = 2VP-P, AV = 2, RL = 150Ω AV = 1, f = 1MHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) TA = 25°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Note 10). SYMBOL VOS IOS IB en in RIN CIN VCM CMRR AVOL VOUT PARAMETER Input Offset Voltage Input Offset Current Input Bias Current Input Noise Voltage Density Input Noise Current Density Input Resistance Input Capacitance Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing (Positive) Maximum Output Swing (Negative) IOUT ISC SR FPBW GBW tr, tf OS tPD ts THD Maximum Output Current Output Short-Circuit Current Slew Rate Full Power Bandwidth Gain Bandwidth Product Rise Time, Fall Time Overshoot Propagation Delay Settling Time Total Harmonic Distortion Differential Gain Differential Phase CONDITIONS (Note 4) MIN TYP 0.5 30 – 1.0 8 1 10 1.5 2 4 1 82 2.0 1.5 4.1 3.9 0.9 1.1 ± 40 ± 80 350 55 94 2.1 25 3 30 –75 0.22 0.21 MAX 2.0 400 ±4 UNITS mV nA µA nV/√Hz pA/√Hz MΩ MΩ pF V V dB V/mV V/mV V V V V mA mA V/µs MHz MHz ns % ns ns dB % DEG f = 10kHz f = 10kHz VCM = 1.5V to 3.5V Differential 3 3.5 VCM = 1.5V to 3.5V VOUT = 1.5V to 3.5V, RL = 500Ω VOUT = 1.5V to 3.5V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = 3.5V or 1.5V, 30mV Overdrive VOUT = 2.5V, 1V Overdrive (Note 3) AV = – 1 (Note 5) 1V Peak (Note 6) f = 200kHz AV = 1, 10% to 90%, 0.1V, RL = 100Ω AV = 1, 0.1V, RL = 100Ω AV = 1, 50% VIN to 50% VOUT, 0.1V, RL = 100Ω 2V Step, 0.1%, AV = – 1 f = 1MHz, VOUT = 2VP-P, AV = 2, RL = 500Ω VOUT = 2VP-P, AV = 2, RL = 150Ω VOUT = 2VP-P, AV = 2, RL = 150Ω 73 1.0 0.7 3.9 3.7 1.5 1.1 1.3 ± 25 ± 55 200 65 3 LT1812 ELECTRICAL CHARACTERISTICS SYMBOL ROUT ISHDN IS PARAMETER Output Resistance SHDN Pin Current Supply Current TA = 25°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Note 10). MIN TYP 0.45 0 – 20 2.7 20 MAX ±1 3.6 50 UNITS Ω µA µA mA µA CONDITIONS AV = 1, f = 1MHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) – 50 0°C ≤ TA ≤ 70°C, VS = ± 5V, VCM = 0V unless otherwise noted (Note 10). SYMBOL VOS ∆VOS/∆T IOS IB VCM CMRR PSRR AVOL VOUT IOUT ISC SR GBW ISHDN IS PARAMETER Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Bias Current Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Minimum Supply Voltage Power Supply Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing Maximum Output Current Output Short-Circuit Current Slew Rate Gain Bandwidth Product SHDN Pin Current Supply Current CONDITIONS (Note 4) (Note 7) MIN TYP 10 MAX 2 15 500 ±5 – 3.5 VCM = ± 3.5V VS = ± 2V to ± 5.5V VOUT = ± 3V, RL = 500Ω VOUT = ± 3V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = ± 3V, 30mV Overdrive VOUT = 0V, 1V Overdrive (Note 3) AV = – 1 (Note 5) f = 200kHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) 73 ±2 76 1.0 0.7 ± 3.70 ± 3.25 ± 35 ± 60 400 65 ± 1.5 –150 4.6 150 UNITS mV µV/°C nA µA V V dB V dB V/mV V/mV V V mA mA V/µs MHz µA µA mA µA 3.5 4 LT1812 ELECTRICAL CHARACTERISTICS 0°C ≤ TA ≤ 70°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Note 10). SYMBOL VOS ∆VOS/∆T IOS IB VCM CMRR AVOL VOUT PARAMETER Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Bias Current Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing (Positive) Maximum Output Swing (Negative) IOUT ISC SR GBW ISHDN IS Maximum Output Current Output Short-Circuit Current Slew Rate Gain Bandwidth Product SHDN Pin Current Supply Current CONDITIONS (Note 4) (Note 7) MIN TYP 10 MAX 2.5 15 500 ±5 1.5 VCM = 1.5V to 3.5V VOUT = 1.5V to 3.5V, RL = 500Ω VOUT = 1.5V to 3.5V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = 3.5V or 1.5V, 30mV Overdrive VOUT = 2.5V, 1V Overdrive (Note 3) AV = – 1 (Note 5) f = 200kHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) 71 0.7 0.5 3.8 3.6 1.2 1.4 ± 20 ± 45 150 55 ±1.5 – 75 4.5 75 UNITS mV µV/°C nA µA V V dB V/mV V/mV V V V V mA mA V/µs MHz µA µA mA µA 3.5 – 40°C ≤ TA ≤ 85°C. VS = ± 5V, VCM = 0V unless otherwise noted (Notes 8, 10). SYMBOL VOS ∆VOS/∆T IOS IB VCM CMRR PSRR AVOL VOUT IOUT ISC SR GBW ISHDN IS PARAMETER Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Bias Current Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Minimum Supply Voltage Power Supply Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing Maximum Output Current Output Short-Circuit Current Slew Rate Gain Bandwidth Product SHDN Pin Current Supply Current CONDITIONS (Note 4) (Note 7) MIN TYP 10 MAX 3 30 600 ±6 – 3.5 VCM = ± 3.5V VS = ± 2V to ± 5.5V VOUT = ± 3V, RL = 500Ω VOUT = ± 3V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = ± 3V, 30mV Overdrive VOUT = 0V, 1V Overdrive (Note 3) AV = – 1 (Note 5) f = 200kHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) 72 ±2 75 0.8 0.6 ± 3.60 ± 3.15 ± 30 ± 55 350 60 ±2 – 200 5 200 UNITS mV µV/°C nA µA V V dB V dB V/mV V/mV V V mA mA V/µs MHz µA µA mA µA 3.5 5 LT1812 ELECTRICAL CHARACTERISTICS – 40°C ≤ TA ≤ 85°C, VS = 5V, VCM = 2.5V, RL to 2.5V unless otherwise noted (Notes 8, 10). SYMBOL VOS ∆VOS/∆T IOS IB VCM CMRR AVOL VOUT PARAMETER Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Bias Current Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Large-Signal Voltage Gain Maximum Output Swing (Positive) Maximum Output Swing (Negative) IOUT ISC SR GBW ISHDN IS Maximum Output Current Output Short-Circuit Current Slew Rate Gain Bandwidth Product SHDN Pin Current Supply Current CONDITIONS (Note 4) (Note 7) MIN TYP 10 MAX 3.5 30 600 ±6 1.5 VCM = 1.5V to 3.5V VOUT = 1.5V to 3.5V, RL = 500Ω VOUT = 2.0V to 3.0V, RL = 100Ω RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive RL = 500Ω, 30mV Overdrive RL = 100Ω, 30mV Overdrive VOUT = 3.5V or 1.5V, 30mV Overdrive VOUT = 2.5V, 1V Overdrive (Note 3) AV = – 1 (Note 5) f = 200kHz SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) SHDN > V – + 2.0V (On) (Note 11) SHDN < V – + 0.4V (Off) (Note 11) 70 0.6 0.4 3.7 3.5 1.3 1.5 ± 17 ± 40 125 50 ±2 – 100 5 100 UNITS mV µV/°C nA µA V V dB V/mV V/mV V V V V mA mA V/µs MHz µA µA mA µA 3.5 Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: Differential inputs of ± 3V are appropriate for transient operation only, such as during slewing. Large sustained differential inputs can cause excessive power dissipation and may damage the part. 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 ± 2V on the output with ± 3V input for ± 5V supplies and 2VP-P on the output with a 3VP-P input for single 5V supplies. Note 6: Full power bandwidth is calculated from the slew rate: FPBW = SR/2πVP. Note 7: This parameter is not 100% tested. Note 8: The LT1812C is guaranteed to meet specified performance from 0°C to 70°C. The LT1812C is designed, characterized and expected to meet specified performance from –40°C to 85°C but is not tested or QA sampled at these temperatures. The LT1812I is guaranteed to meet specified performance from –40°C to 85°C. Note 9: Thermal resistance varies with the amount of PC board metal connected to the package. The nominal values are for short traces connected to the pins. The thermal resistance can be substantially reduced by connecting Pin 2 of the 5-lead or 6-lead SOT-23 or Pin 4 of the SO-8 to a large metal area. Note 10: For the 8-lead SO and 6-lead SOT-23 parts, the electrical characteristics apply to the “ON” state, unless otherwise noted. These parts are in the “ON” state when either SHDN is not connected, or SHDN > V – + 2.0V. Note 11: The shutdown (SHDN) feature is not available on the 5-lead SOT-23 parts. These parts are always in the “ON” state. 6 LT1812 TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Temperature 5 INPUT COMMON MODE RANGE (V) INPUT BIAS CURRENT (µA) 4 SUPPLY CURRENT (mA) VS = ± 5V 3 VS = ± 2.5V 2 1 0 –50 –25 50 25 0 75 TEMPERATURE (°C) Input Bias Current vs Temperature 0 INPUT VOLTAGE NOISE (nV/√Hz) –0.2 INPUT BIAS CURRENT (µA) –0.4 –0.6 –0.8 –1.0 –1.2 –1.4 –50 –25 VS = ± 5V VS = ± 2.5V OPEN-LOOP GAIN (dB) 50 25 75 0 TEMPERATURE (°C) Open-Loop Gain vs Temperature 75.0 72.5 VS = ± 5V VO = ± 3V V+ – 0.5 OUTPUT VOLTAGE SWING (V) –1.0 –1.5 – 2.0 RL = 100Ω OUTPUT VOLTAGE SWING (V) OPEN-LOOP GAIN (dB) 70.0 67.5 65.0 62.5 60.0 –50 –25 RL = 500Ω RL = 100Ω 50 25 75 0 TEMPERATURE (°C) UW 100 1812 G01 Input Common Mode Range vs Supply Voltage V+ – 0.5 –1.0 –1.5 – 2.0 TA = 25°C ∆VOS < 1mV 2.0 1.5 1.0 0.5 V– 125 0 1 4 3 2 5 SUPPLY VOLTAGE (± V) 6 7 1812 G02 Input Bias Current vs Common Mode Voltage 0 TA = 25°C VS = ± 5V – 0.5 –1.0 –1.5 – 2.0 – 5.0 0 2.5 – 2.5 INPUT COMMON MODE VOLTAGE (V) 5.0 1812 G03 Input Noise Spectral Density 100 TA = 25°C VS = ± 5V AV = 101 RS = 10k 10 INPUT CURRENT NOISE (pA/√Hz) 75.0 72.5 70.0 Open-Loop Gain vs Resistive Load TA = 25°C in 10 en 1 VS = ± 5V 67.5 VS = ± 2.5V 65.0 62.5 60 100 1 100 125 10 100 1k 10k FREQUENCY (Hz) 0.1 100k 1812 G05 1k LOAD RESISTANCE (Ω) 10k 1812 G06 1812 G04 Output Voltage Swing vs Supply Voltage TA = 25°C VIN = 30mV V+ RL = 500Ω – 0.5 –1.0 –1.5 – 2.0 Output Voltage Swing vs Load Current VS = ± 5V VIN = 30mV 85°C 25°C – 40°C 2.0 1.5 1.0 0.5 V– RL = 500Ω 0 1 4 3 2 5 SUPPLY VOLTAGE (± V) 6 7 1812 G08 2.0 1.5 1.0 0.5 V– –60 –40 0 20 40 –20 OUTPUT CURRENT (mA) 60 1812 G09 RL = 100Ω 100 125 1812 G07 7 LT1812 TYPICAL PERFOR A CE CHARACTERISTICS Output Short-Circuit Current vs Temperature 120 OUTPUT SHORT-CIRCUIT CURRENT (mA) VS = ± 5V SOURCE 115 110 SINK 105 100 95 90 –50 –25 GAIN (dB) 30 ± 2.5V 20 10 0 ± 2.5V ± 5V ± 5V GAIN (dB) 50 25 75 0 TEMPERATURE (°C) Settling Time vs Output Step 5 4 3 GAIN BANDWIDTH (MHz) OUTPUT STEP (V) 2 1 0 –1 –2 –3 –4 –5 0 TA = 25°C VS = ± 5V AV = –1 RF = 500Ω CF = 3pF 0.1% SETTLING 5 20 15 10 25 SETTLING TIME (ns) 30 35 GAIN (dB) Output Impedance vs Frequency 100 AV = 100 GAIN BANDWIDTH (MHz) AV = 10 1 AV = 1 115 10 OUTPUT IMPEDANCE (Ω) GAIN (dB) 0.1 0.01 TA = 25°C VS = ± 5V 100k 1M 10M FREQUENCY (Hz) 100M 1812 G12 0.001 10k 8 UW 100 1812 G10 1812 G11 Open-Loop Gain and Phase vs Frequency 70 60 50 GAIN 40 PHASE PHASE (DEG) Gain vs Frequency 120 100 80 60 40 20 0 –20 6 4 2 0 –2 –4 –6 –8 –10 –12 –14 1M 10M 100M FREQUENCY (Hz) 500M 1812 G16 TA = 25°C AV = – 1 RF = RG = 500Ω TA = 25°C AV = 1 NO RL VS = ± 2.5V VS = ± 5V 125 –10 10k 100k 1M 10M FREQUENCY (Hz) 100M –40 1000M 1812 G13 Gain Bandwidth and Phase Margin vs Supply Voltage 110 TA = 25°C 8 GBW RL = 500Ω PHASE MARGIN (DEG) Gain vs Frequency 6 4 2 VS = ± 2.5V 0 –2 –4 35 7 1812 G19 TA = 25°C AV = 2 RL = 100Ω 90 GBW RL = 100Ω 70 PHASE MARGIN RL = 100Ω 40 PHASE MARGIN RL = 500Ω 0 1 5 4 3 SUPPLY VOLTAGE (± V) 2 6 45 VS = ± 5V –6 1M 10M 100M FREQUENCY (Hz) 500M 1812 G17 Gain Bandwidth and Phase Margin vs Temperature RL = 500Ω GBW VS = ± 5V GBW VS = ± 2.5V 12 Gain vs Frequency TA = 25°C AV = – 1 V = ± 5V 8S RF = RG = 500Ω NO RL 4 CL= 1000pF CL= 500pF CL= 200pF CL= 100pF CL= 50pF CL= 0 105 PHASE MARGIN (DEG) 95 85 PHASE MARGIN VS = ± 5V PHASE MARGIN VS = ± 2.5V 40 0 38 –4 –50 –25 50 25 0 75 TEMPERATURE (°C) 100 36 125 –8 1 10M FREQUENCY (Hz) 100M 200M 1812 G18 1812 G15 LT1812 TYPICAL PERFOR A CE CHARACTERISTICS Shutdown Supply Current vs Temperature 70 POWER SUPPLY REJECTION RATIO (dB) 60 50 40 30 20 10 0 –50 –25 VS = ± 5V 80 –PSRR +PSRR 40 COMMON MODE REJECTION RATIO (dB) VSHDN = V – + 0.4V SHUTDOWN SUPPLY CURRENT (µA) VS = ± 2.5V 50 25 75 0 TEMPERATURE (°C) Slew Rate vs Supply Voltage 1200 TA =25°C 1100 AV = – 1 /2 V =V 1000 RIN= R S(TOTAL)500Ω F G = RL = 900 800 700 600 500 400 300 200 0 1 4 3 2 5 SUPPLY VOLTAGE (± V) 6 7 1812 G22 SLEW RATE (V/µs) SLEW RATE (V/µs) SR – SR + SR – 400 SR + 300 SLEW RATE (V/µs) Slew Rate vs Temperature TOTAL HARMONIC DISTORTION + NOISE (%) 1200 1000 SR– VS = ± 5V SLEW RATE (V/µs) 800 600 400 200 0 –50 –25 SR+ VS = ± 2.5V 0.005 AV = 1 OUTPUT VOLTAGE (VP-P) SR – VS = ± 2.5V 50 25 75 0 TEMPERATURE (°C) UW 100 1812 G14 Power Supply Rejection Ratio vs Frequency 100 TA = 25°C AV = 1 VS = ± 5V 100 Common Mode Rejection Ratio vs Frequency TA = 25°C VS = ± 5V 80 60 60 40 20 20 0 125 1k 10k 1M 100k FREQUENCY (Hz) 10M 100M 1812 G20 0 1k 10k 100k 1M FREQUENCY (Hz) 10M 100M 1812 G21 Slew Rate vs Supply Voltage 600 TA =25°C AV = – 1 VIN = ± 1V 500 RF = RG = RL = 500Ω 1200 Slew Rate vs Input Level TA =25°C AV = – 1 V = ± 5V 1000 RS = R = R = 500Ω F G L 800 SR – SR + 600 400 200 0 1 4 3 2 5 SUPPLY VOLTAGE (± V) 6 7 1812 G23 200 0 1 2 4 3 5 6 INPUT LEVEL (VP-P) 7 8 1812 G24 Total Harmonic Distortion + Noise vs Frequency 0.01 9 8 Undistorted Output Swing vs Frequency AV = – 1 AV = 1 SR+ VS = ± 5V AV = – 1 7 6 5 4 3 2 1 0.002 0.001 10 TA = 25°C VS = ± 5V VO = 2VP-P RL = 500Ω 100 1k 10k FREQUENCY (Hz) 100k 1812 G26 100 125 0 100k TA = 25°C VS = ± 5V RL = 100Ω 2% MAX DISTORTION 1M 10M FREQUENCY (Hz) 100M 1812 G27 1812 G25 9 LT1812 TYPICAL PERFOR A CE CHARACTERISTICS 2nd and 3rd Harmonic Distortion vs Frequency –30 –40 HARMONIC DISTORTION (dB) –50 –60 –70 –80 3RD HARMONIC –90 –100 100k 2ND HARMONIC RL = 500Ω 1M FREQUENCY (Hz) 10M 1812 G28 DIFFERENTIAL PHASE (DEG) TA = 25°C AV = 2 VS = ± 5V VO = 2VP-P 2ND HARMONIC 3RD HARMONIC RL = 100Ω DIFFERENTIAL GAIN RL = 1 k 0.25 0.20 0.15 0.10 0.05 0 TA = 25°C 4 10 8 6 TOTAL SUPPLY VOLTAGE (V) 12 1812 G29 OVERSHOOT (%) Small-Signal Transient, AV = – 1 Large-Signal Transient, AV = – 1 10 UW 1812 G31 1812 G34 Differential Gain and Phase vs Supply Voltage 0.25 DIFFERENTIAL GAIN RL = 150Ω 0.20 0.15 Capacitive Load Handling 100 90 80 DIFFERENTIAL GAIN (%) 70 60 50 40 30 20 10 0 10 100 1000 CAPACITIVE LOAD (pF) 10000 1812 G30 TA = 25°C VS = ± 5V AV = 1 0.10 0.05 0 DIFFERENTIAL PHASE RL = 150Ω DIFFERENTIAL PHASE RL = 1 k AV = – 1 Small-Signal Transient, AV = 1 Small-Signal Transient, AV = 1, CL = 1000pF 1812 G32 1812 G33 Large-Signal Transient, AV = 1 Large-Signal Transient, AV = 1, CL = 1000pF 1812 G35 1812 G36 LT1812 APPLICATIO S I FOR ATIO Layout and Passive Components The LT1812 amplifier is more tolerant of less than ideal layouts than other high speed amplifiers. For maximum performance (for example, fast 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 that can cause peaking or even oscillations. If feedback resistors greater than 2k are used, a parallel capacitor of value CF > RG • CIN/RF should be used to cancel the input pole and optimize dynamic performance. For applications where the DC noise gain is 1 and a large feedback resistor is used, CF should be greater than or equal to CIN. An example would be an I-to-V converter. Input Considerations Each of the LT1812 amplifier inputs is the base of an NPN and 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 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. The inputs can withstand differential input voltages of up to 3V without damage and need no clamping or source resistance for protection. The device should not be used as a comparator because with sustained differential inputs, excessive power dissipation may result. Capacitive Loading The LT1812 is stable with a 1000pF capacitive load, which is outstanding for a 100MHz amplifier. This is accomplished by sensing the load induced output pole and adding compensation at the amplifier gain node. As the U capacitive load increases, both the bandwidth and phase margin decrease so there will be peaking in the frequency domain and in the transient response. 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. Slew Rate The slew rate is proportional to the differential input voltage. Highest slew rates are therefore seen in the lowest gain configurations. For example, a 5V output step in a gain of 10 has a 0.5V input step, whereas in unity gain there is a 5V input step. The LT1812 is tested for slew rate in a gain of – 1. Lower slew rates occur in higher gain configurations. Shutdown The LT1812 has a shutdown pin (SHDN, Pin 8) for conserving power. When this pin is open or biased at least 2V above the negative supply, the part operates normally. When pulled down to V –, the supply current drops to about 50µA. Typically, the turn-off delay is 1µs and the turn-on delay 0.5µs. The current out of the SHDN pin is also typically 50µA. In shutdown mode, the amplifier output is not isolated from the inputs, so the LT1812 shutdown feature cannot be used for multiplexing applications. The 50µA typical shutdown current is exclusive of any output (load) current. In order to prevent load current (and maximize the power savings), either the load needs to be disconnected, or the input signal needs to be 0V. Even in shutdown mode, the LT1812 can still drive significant current into a load. For example, in an AV = 1 configuration, when driven with a 1V DC input, the LT1812 drives 2mA into a 100Ω load. It takes about 500µs for the load current to reach this value. Power Dissipation The LT1812 combines high speed and large output drive in a small package. It is possible to exceed the maximum junction temperature under certain conditions. Maximum W UU 11 LT1812 APPLICATIO S I FOR ATIO TJ = TA + (PD • θJA) (Note 9) Power dissipation is composed of two parts. The first is due to the quiescent supply current and the second is due to on-chip dissipation caused by the load current. The worst-case load induced power occurs when the output voltage is at 1/2 of either supply voltage (or the maximum swing if less than 1/2 supply voltage). Therefore PDMAX is: PDMAX = (V + – V – )(ISMAX) + (V +/2)2/RL or PDMAX = (V + – V – )(ISMAX) + (V + – VOMAX)(VOMAX/RL) Example: LT1812CS5 at 70°C, VS = ± 5V, RL = 100Ω PDMAX = (10V)(4.5mA) + (2.5V)2/100Ω = 108mW TJMAX = 70°C + (108mW)(250°C/W) = 97°C Circuit Operation The LT1812 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 that drive a 300Ω resistor. The input voltage junction temperature (TJ) is calculated from the ambient temperature (TA) and power dissipation (PD) as follows: SI PLIFIED SCHEMATIC V+ RB –IN C BIAS CONTROL SHDN V– 1812 SS 12 U appears across the resistor generating currents that are mirrored into the high impedance node. Complementary followers form an output stage that 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. 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 capacitive loads (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 unitygain cross 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 the total phase lag does not exceed 180 degrees (zero phase margin) and the amplifier remains stable. In this way, the LT1812 is stable with up to 1000pF capacitive loads in unity gain, and even higher capacitive loads in higher closed-loop gain configurations. R1 300Ω +IN RC CC OUT W W UU W LT1812 PACKAGE DESCRIPTION 0.35 – 0.55 (0.014 – 0.022) NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DIMENSIONS ARE INCLUSIVE OF PLATING 3. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 4. MOLD FLASH SHALL NOT EXCEED 0.254mm 5. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ) U Dimensions in inches (millimeters) unless otherwise noted. S5 Package 5-Lead Plastic SOT-23 (LTC DWG # 05-08-1633) 2.80 – 3.00 (0.110 – 0.118) (NOTE 3) 2.60 – 3.00 (0.102 – 0.118) 1.50 – 1.75 (0.059 – 0.069) 1.90 (0.074) REF 0.00 – 0.15 (0.00 – 0.006) 0.95 (0.037) REF 0.90 – 1.45 (0.035 – 0.057) 0.09 – 0.20 (0.004 – 0.008) (NOTE 2) 0.35 – 0.50 0.90 – 1.30 (0.014 – 0.020) (0.035 – 0.051) FIVE PLACES (NOTE 2) S5 SOT-23 0599 13 LT1812 PACKAGE DESCRIPTION 0.35 – 0.55 (0.014 – 0.022) NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DIMENSIONS ARE INCLUSIVE OF PLATING 3. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 4. MOLD FLASH SHALL NOT EXCEED 0.254mm 5. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ) 14 U Dimensions in inches (millimeters) unless otherwise noted. S6 Package 6-Lead Plastic SOT-23 (LTC DWG # 05-08-1634) 2.80 – 3.00 (0.110 – 0.118) (NOTE 3) 2.6 – 3.0 (0.110 – 0.118) 1.50 – 1.75 (0.059 – 0.069) 1.90 (0.074) REF 0.00 – 0.15 (0.00 – 0.006) 0.95 (0.037) REF 0.90 – 1.45 (0.035 – 0.057) 0.09 – 0.20 (0.004 – 0.008) (NOTE 2) 0.35 – 0.50 0.90 – 1.30 (0.014 – 0.020) (0.035 – 0.051) SIX PLACES (NOTE 2) S6 SOT-23 0898 LT1812 PACKAGE DESCRIPTION 0.010 – 0.020 × 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) 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. 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) SO8 1298 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 15 LT1812 TYPICAL APPLICATIO VIN 2VP-P 2.5VDC RELATED PARTS PART NUMBER LT1360/LT1361/LT1362 LT1363/LT1364/LT1365 LT1395/LT1396/LT1397 LT1806 LT1809 LT1813 DESCRIPTION Single/Dual/Quad 50MHz, 800V/µs, C-LoadTM Amplifiers Single/Dual/Quad 70MHz, 1000V/µs C-Load Amplifiers Single/Dual/Quad 400MHz Current Feedback Amplifiers 325MHz, 140V/µs Rail-to-Rail I/O Op Amp 180MHz, 350V/µs Rail-to-Rail I/O Op Amp Dual 3mA, 100MHz, 750V/µs Operational Amplifier COMMENTS 4mA Supply Current, 1mV Max VOS, 1µA Max IB 50mA Output Current, 1.5mV Max VOS, 2µA Max IB 4.6mA Supply Current, 800V/µs, 80mA Output Current Low Noise 3.5nV/√Hz Low Distortion –90dBc at 5MHz Dual Version of the LT1812 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 Single 5V Supply 10MS/s 12-Bit ADC Buffer + LT1812 68Ω LTC1420 12 BITS – 470pF 1812 TA03 10MS/s 1812fa LT/TP 1000 REV A 2K • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1999