LT1220 45MHz, 250V/µs Operational Amplifier U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO The LT®1220 is a high speed operational amplifier with superior DC performance. The LT1220 features reduced input offset voltage, lower input bias currents and higher DC gain than devices with comparable bandwidth and slew rate. The circuit is a single gain stage that includes proprietary DC gain enhancement circuitry to obtain precision with high speed. The high gain and fast settling time make the circuit an ideal choice for data acquisition systems. The circuit is also capable of driving large capacitive loads which makes it useful in buffer or cable driver applications. Gain-Bandwidth: 45MHz Unity-Gain Stable Slew Rate: 250V/µs C-LoadTM Op Amp Drives Capacitive Loads Maximum Input Offset Voltage: 1mV Maximum Input Bias Current: 300nA Maximum Input Offset Current: 300nA Minimum Output Swing Into 500Ω: ±12V Minimum DC Gain: 20V/mV, RL = 500Ω Settling Time to 0.1%: 75ns, 10V Step Settling Time to 0.01%: 95ns, 10V Step Differential Gain: 0.1%, AV = 2, RL = 150Ω Differential Phase: 0.2°, AV = 2, RL = 150Ω The LT1220 is a member of a family of fast, high performance amplifiers that employ Linear Technology Corporation’s advanced complementary bipolar processing. For applications with gains of 4 or greater the LT1221 can be used, and for gains of 10 or greater the LT1222 can be used for increased bandwidth. U APPLICATIO S ■ ■ ■ ■ ■ Wideband Amplifiers Buffers Active Filters Video and RF Amplification Cable Drivers 8-, 10-, 12-Bit Data Acquisition Systems , LTC and LT are registered trademarks of Linear Technology Corporation C-Load is a trademark of Linear Technology Corporation U ■ TYPICAL APPLICATIO Two Op Amp Instrumentation Amplifier R5 220Ω R1 10k R2 1k – LT1220 – VIN Inverter Pulse Response R4 10k + R3 1k – LT1220 + VOUT + GAIN = [R4/R3][1 + (1/2)(R2/R1 + R3/R4) + (R2 + R3)/R5] = 102 TRIM R5 FOR GAIN TRIM R1 FOR COMMON MODE REJECTION BW = 450kHz LT1220 • TA01 RF = RG = 1k VS = ±15V VIN = 20V f = 2MHz LT1220 • TA02 1 LT1220 W W W AXI U U ABSOLUTE RATI GS (Note 1) Total Supply Voltage (V + to V –) .............................. 36V Differential Input Voltage ........................................ ±6V Input Voltage .......................................................... ±VS Output Short-Circuit Duration (Note 2) ........... Indefinite Specified Temperature Range LT1220C (Note 3) ................................... 0°C to 70°C LT1220M (OBSOLETE) ............... – 55°C to 125°C Operating Temperature Range LT1220C ........................................... – 40°C TO 85°C LT1220M (OBSOLETE) ............... – 55°C to 150°C Maximum Junction Temperature (See Below) Plastic Package ............................................... 150°C Ceramic Package (OBSOLETE) .................. 175°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C U W U PACKAGE/ORDER I FOR ATIO 8 NULL 1 7 V+ 6 VOUT –IN 2 +IN 3 TOP VIEW ORDER PART NUMBER TOP VIEW NULL LT1220CH LT1220MH 5 NC NULL 1 8 NULL –IN 2 7 V+ +IN 3 6 VOUT V– 4 5 NC ORDER PART NUMBER LT1220CN8 LT1220CS8 S8 PART MARKING S8 PACKAGE N8 PACKAGE 8-LEAD PLASTIC DIP 8-LEAD PLASTIC SOIC TJMAX = 150°C, θJA = 130°C/W (N) TJMAX = 150°C, θJA = 190°C/W (S) J8 PACKAGE 8-LEAD CERAMIC DIP TJMAX = 175°C, θJA = 100°C/W (J) 4 V– H PACKAGE 8-LEAD TO-5 METAL CAN TJMAX = 175°C, θJA = 150°C/W 1220 ORDER PART NUMBER OBSOLETE PACKAGE LT1220MJ8 OBSOLETE PACKAGE Consider the N8 or S8 Packages for Alternate Source Consider the N8 Package for Alternate Source Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS SYMBOL VOS IOS IB en in RIN PARAMETER Input Offset Voltage Input Offset Current Input Bias Current Input Noise Voltage Input Noise Current Input Resistance CIN Input Capacitance Input Voltage Range (Positive) Input Voltage Range (Negative) Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain Output Swing Output Current Slew Rate Full Power Bandwidth Gain-Bandwidth CMRR PSRR AVOL VOUT IOUT SR GBW 2 TA = 25°C, VS = ±15V, VCM = 0V, unless otherwise specified. CONDITIONS (Note 4) f = 10kHz f = 10kHz VCM = ±12V Differential MIN 20 12 VCM = ±12V VS = ±5V to ±15V VOUT = ±10V, RL = 500Ω RL = 500Ω VOUT = ±12V (Note 5) 10V Peak (Note 6) f = 1MHz 92 90 20 12 24 200 TYP 0.5 100 100 17 2 45 150 2 14 – 13 114 94 50 13 26 250 4 45 MAX 1 300 300 – 12 UNITS mV nA nA nV/√Hz pA/√Hz MΩ kΩ pF V V dB dB V/mV ±V mA V/µs MHz MHz LT1220 ELECTRICAL CHARACTERISTICS SYMBOL tr, tf ts PARAMETER Rise Time, Fall Time Overshoot Propagation Delay Settling Time Differential Gain Differential Phase RO IS Output Resistance Supply Current VS = ±15V, TA = 25°C, VCM = 0V, unless otherwise specified. CONDITIONS AV = 1, 10% to 90%, 0.1V AV = 1, 0.1V AV = 1, 50% VIN to 50% VOUT, 0.1V 10V Step, 0.1% 10V Step, 0.01% f = 3.58MHz, RL = 150Ω (Note 7) f = 3.58MHz, RL = 1k (Note 7) f = 3.58MHz, RL = 150Ω (Note 7) f = 3.58MHz, RL = 1k (Note 7) AV = 1, f = 1MHz MIN TYP 2.5 5 4.9 75 95 0.10 0.02 0.20 0.03 1 8 MAX 10.5 UNITS ns % ns ns ns % % DEG DEG Ω mA The ● denotes the specifications which apply over the temperature range 0°C ≤ TA ≤ 70°C, otherwise specifications are at TA = 25°C. VS = ±15V, VCM = 0V, unless otherwise specified. SYMBOL VOS IOS IB CMRR PSRR AVOL VOUT IOUT SR IS PARAMETER Input Offset Voltage Input VOS Drift Input Offset Current Input Bias Current Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain Output Swing Output Current Slew Rate Supply Current CONDITIONS (Note 4) MIN ● ● ● ● VCM = ±12V VS = ±5V to ±15V VOUT = ±10V, RL = 500Ω RL = 500Ω VOUT = ±12V (Note 5) ● ● ● ● ● ● 92 86 20 12 24 180 ● TYP 0.5 20 100 100 114 94 50 13 26 250 8 MAX 3.5 400 400 11 UNITS mV µV/°C nA nA dB dB V/mV ±V mA V/µs mA The ● denotes the specifications which apply over the temperature range – 55°C ≤ TA ≤ 125°C, otherwise specifications are at TA = 25°C. VS = ±15V, VCM = 0V, unless otherwise specified. SYMBOL VOS IOS IB CMRR PSRR AVOL VOUT PARAMETER Input Offset Voltage Input VOS Drift Input Offset Current Input Bias Current Common Mode Rejection Ratio Power Supply Rejection Ratio Large-Signal Voltage Gain Output Swing IOUT Output Current SR IS Slew Rate Supply Current CONDITIONS (Note 4) MIN ● ● ● ● VCM = ±12V VS = ±5V to ±15V VOUT = ±10V, RL = 500Ω RL = 500Ω RL = 1k VOUT = ±10V VOUT = ±12V (Note 5) 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 when the output is shorted indefinitely. Note 3: Commercial parts are designed to operate over – 40°C to 85°C, but are not tested nor guaranteed beyond 0°C to 70°C. Industrial grade parts specified and tested over –40°C to 85°C are available on special request. Consult factory. ● ● ● ● ● ● ● ● ● 92 82 5 10 12 20 12 130 TYP 0.5 20 100 100 114 94 50 13 13 26 13 250 8 MAX 4 800 1000 11 UNITS mV µV/°C nA nA dB dB V/mV ±V ±V mA mA V/µs mA Note 4: Input offset voltage is pulse tested and is exclusive of warm-up drift. Note 5: Slew rate is measured between ±10V on an output swing of ±12V. Note 6: FPBW = SR/2πVP. Note 7: Differential Gain and Phase are tested in AV = 2 with five amps in series. Attenuators of 1/2 are used as loads (75Ω, 75Ω and 499Ω, 499Ω). 3 LT1220 U W TYPICAL PERFORMANCE CHARACTERISTICS Input Common Mode Range vs Supply Voltage Supply Current vs Supply Voltage and Temperature 15 +VCM 10 –VCM 5 MAGNITUDE OF OUTPUT VOLATGE (V) TA = 25°C TA = 25°C ∆VOS = 0.5mV SUPPLY CURRENT (mA) 8.5 8.0 7.5 0 5 10 15 SUPPLY VOLTAGE (±V) 5 10 15 SUPPLY VOLTAGE (±V) 0 20 15 +VSW 10 –VSW 5 Output Voltage Swing vs Resistive Load 500 30 TA = 25°C ∆VOS = 30mV INPUT BIAS CURRENT (nA) ±15V SUPPLIES 15 10 ±5V SUPPLIES 5 Open-Loop Gain vs Resistive Load 110 TA = 25°C VS = ±15V 400 20 LT1220 • TPC03 Input Bias Current vs Input Common Mode Voltage 20 5 10 15 SUPPLY VOLTAGE (±V) 0 20 LT1220 • TPC02 LT1220 • TPC01 25 TA = 25°C RL = 500Ω ∆VOS = 30mV 0 7.0 0 TA = 25°C 300 100 200 OPEN-LOOP GAIN (dB) MAGNITUDE OF INPUT VOLTAGE (V) 20 9.0 20 OUTPUT VOLTAGE SWING (VP-P) Output Voltage Swing vs Supply Voltage IB+ 100 IB– 0 –100 –200 –300 VS = ±15V 90 VS = ±5V 80 70 – 400 0 100 1k LOAD RESISTANCE (Ω) 10k – 500 –15 60 –10 –5 10 0 5 INPUT COMMON MODE VOLTAGE (V) Output Short-Circuit Current vs Temperature INPUT VOLTAGE NOISE (nV/√Hz) OUTPUT SHORT-CIRCUIT CURRENT (mA) 35 30 25 120 100 80 60 40 20 0 –25 0 25 75 50 TEMPERATURE (°C) 100 125 LT1220 • TPC07 4 100 VS = ±15V TA = 25°C AV = 100 140 40 20 –50 Power Supply Rejection Ratio vs Frequency 160 VS = ±5V 10k LT1220 • TPC06 Input Noise Spectral Density 45 100 1k LOAD RESISTANCE (Ω) 10 LT1220 • TPC05 LT1220 • TPC04 50 15 POWER SUPPLY REJECTION RATIO (dB) 10 10 100 1k 10k FREQUENCY (Hz) 100k LT1220 • TPC08 VS = ±15V TA = 25°C 80 60 +PSRR 40 –PSRR 20 0 100 1k 100k 1M 10k FREQUENCY (Hz) 10M 100M LT1220 • TPC09 LT1220 U W TYPICAL PERFORMANCE CHARACTERISTICS Common Mode Rejection Ratio vs Frequency 100 10 8 8 6 60 40 6 10mV 4 2 0 –2 –4 10mV –6 20 10M 100k 1M FREQUENCY (Hz) –8 25 0 100 75 100 50 SETTLING TIME (ns) 125 60 60 40 40 VS = ±15V 20 VS = ±5V 2 0 C = 100pF –2 C = 50pF –4 –8 10M –20 100M C=0 C = 500pF –6 TA = 25°C 100k 1M 10k FREQUENCY (Hz) VS = ±15V TA = 25°C AV = 1 4 0 C = 1000pF 10 FREQUENCY (MHz) 1 LT1220 • TPC13 0.1 100 275 SLEW RATE (V/µs) 48 44 42 40 VS = ±15V AV = –1 RIN = RF = 1k +SR 250 –SR 225 200 175 125 LT1220 • TPC16 1M 10M FREQUENCY (Hz) 150 –50 –25 0 25 75 50 TEMPERATURE (°C) 100M Total Harmonic Distortion vs Frequency 300 46 100k LT1220 • TPC15 Slew Rate vs Temperature VS = ±15V 100 1 LT1220 • TPC14 50 0 25 75 50 TEMPERATURE (°C) 10 0.01 10k –10 Gain-Bandwidth vs Temperature 125 100 6 VOLTAGE MAGNITUDE (dB) VS = ±5V 0 75 100 50 SETTLING TIME (ns) Closed-Loop Output Impedance vs Frequency VS = ±15V TA = 25°C AV = –1 8 80 20 25 0 1mV LT1220 • TPC12 10 PHASE MARGIN (DEG) VOLTAGE GAIN (dB) 80 10mV LT1220 • TPC11 VS = ±15V –25 –4 Frequency Response vs Capacitive Load 100 38 –50 –2 –10 Voltage Gain and Phase vs Frequency 1k 0 –8 LT1220 • TPC10 –20 100 2 –10 100M 1mV 10mV 4 –6 OUTPUT IMPEDANCE (Ω) 10k 1mV TOTAL HARMONIC DISTORTION AND NOISE (%) 1k 1mV OUTPUT SWING (V) 80 0 GAIN-BANDWIDTH (MHz) Output Swing and Error vs Settling Time (Inverting) 10 VS = ±15V TA = 25°C OUTPUT SWING (V) COMMON MODE REJECTION RATIO (dB) 120 Output Swing and Error vs Settling Time (Noninverting) 100 125 LT1220 • TPC24 0.01 VS = ±15V VO = 3VRMS RL = 500Ω AV = –1 0.001 AV = 1 0.0001 10 100 1k 10k FREQUENCY (Hz) 100k LT1220 • TPC18 5 LT1220 U W TYPICAL PERFORMANCE CHARACTERISTICS Small Signal, AV = 1 VIN = 100mV f = 5MHz LT1220 • TPC19 RG = 0 VS = ±15V LT1220 • TPC20 VIN = 100mV f = 5MHz LT1220 • TPC22 RF = RG = 1k VS = ±15V VIN = 20V f = 2MHz RG = 0 VS = ±15V VIN = 10V f = 20kHz LT1220 • TPC21 Small Signal, AV = – 1, CL = 1,000pF Large Signal, AV = – 1 Small Signal, AV = – 1 U W RF = RG = 1k VS = ±15V VIN = 20V f = 2MHz LT1220 • TPC23 RF = RG = 1k VS = ±15V VIN = 200mV f = 200kHz LT1220 • TPC24 U RG = 0 VS = ±15V Large Signal, AV = 1, CL = 10,000pF Large Signal, AV = 1 U APPLICATIONS INFORMATION The LT1220 may be inserted directly into HA2505/15/25, HA2541/2/4, AD817, AD847, EL2020, EL2044 and LM6361 applications, provided that the nulling circuitry is removed. The suggested nulling circuit for the LT1220 is shown in the following figure. Offset Nulling V+ 5k 1 3 + 0.1µF 8 7 LT1220 2 – 6 4 0.1µF V– 6 LT1220 • AI01 Layout and Passive Components The LT1220 amplifier is easy to apply and tolerant of less than ideal layouts. For maximum performance (for example, fast settling time) use a ground plane, short lead lengths and RF-quality bypass capacitors (0.01µF to 0.1µF). For high driver current applications use low ESR bypass capacitors (1µF to 10µF tantalum). Sockets should be avoided when maximum frequency performance is required, although low profile sockets can provide reasonable performance up to 50MHz. For more details see Design Note 50. Feedback resistors greater than 5k are not recommended because a pole is formed with the input capacitance which can cause peaking or oscillations. LT1220 U U W U APPLICATIONS INFORMATION Input Considerations Bias current cancellation circuitry is employed on the inputs of the LT1220 so the input bias current and input offset current have identical specifications. For this reason, matching the impedance on the inputs to reduce bias current errors is not necessary. Capacitive Loading The LT1220 is stable with capacitive loads. 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. There will be peaking in the frequency domain as shown in the curve of Frequency Response vs Capacitive Load. The small-signal transient response will have more overshoot as shown in the photo of the small-signal response with 1000pF load. The large-signal response with a 10,000pF load shows the output slew rate being limited to 4V/µs by the short-circuit current. The LT1220 can drive coaxial cable 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. DAC Current-to-Voltage Amplifier The high gain, low offset voltage, low input bias current, and fast settling of the LT1220 make it particularly useful as an I/V converter for current output DACs. A typical application is shown with a 565A type, 12-bit, 2mA fullscale output current DAC. The 5k resistor around the LT1220 is internal to the DAC and gives a 10V full-scale output voltage. A 5pF capacitor in parallel with the feedback resistor compensates for the DAC output capacitance and improves settling. The output of the LT1220 settles to 1/2LSB (1.2mV) in less than 300ns. The accuracy of this circuit is equal to: VERROR = VOS + (IOS • 5kΩ) + (VOUT/AVOL) At room temperature the worst-case error is 3mV (1.2LSB). Typically the error is 1.2mV (1/2LSB). Over the commercial temperature range the worse-case error is 6mV (2.5LSB). W W SI PLIFIED SCHE ATIC V+ 7 NULL 1 8 BIAS 1 BIAS 2 6 OUT +IN 3 2 –IN V– 4 LT1220 • SS 7 LT1220 U PACKAGE DESCRIPTIO H Package 8-Lead TO-5 Metal Can (.200 Inch PCD) (Reference LTC DWG # 05-08-1320) 0.335 – 0.370 (8.509 – 9.398) DIA 0.305 – 0.335 (7.747 – 8.509) 0.040 (1.016) MAX 0.050 (1.270) MAX SEATING PLANE 0.165 – 0.185 (4.191 – 4.699) GAUGE PLANE 0.010 – 0.045* (0.254 – 1.143) REFERENCE PLANE 0.500 – 0.750 (12.700 – 19.050) 0.016 – 0.021** (0.406 – 0.533) 0.027 – 0.045 (0.686 – 1.143) 45°TYP 0.028 – 0.034 (0.711 – 0.864) PIN 1 0.200 (5.080) TYP 0.110 – 0.160 (2.794 – 4.064) INSULATING STANDOFF *LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND 0.045" BELOW THE REFERENCE PLANE 0.016 – 0.024 **FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 – 0.610) H8(TO-5) 0.200 PCD 1197 OBSOLETE PACKAGE 8 LT1220 U PACKAGE DESCRIPTIO J8 Package 8-Lead CERDIP (Narrow .300 Inch, Hermetic) (Reference LTC DWG # 05-08-1110) CORNER LEADS OPTION (4 PLCS) 0.023 – 0.045 (0.584 – 1.143) HALF LEAD OPTION 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION 0.005 (0.127) MIN 0.405 (10.287) MAX 8 7 6 5 0.025 (0.635) RAD TYP 0.220 – 0.310 (5.588 – 7.874) 1 2 0.300 BSC (0.762 BSC) 3 4 0.200 (5.080) MAX 0.015 – 0.060 (0.381 – 1.524) 0.008 – 0.018 (0.203 – 0.457) 0° – 15° NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS 0.045 – 0.065 (1.143 – 1.651) 0.014 – 0.026 (0.360 – 0.660) 0.100 (2.54) BSC 0.125 3.175 MIN J8 1298 OBSOLETE PACKAGE 9 LT1220 U PACKAGE DESCRIPTIO N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) 0.400* (10.160) MAX 8 7 6 5 1 2 3 4 0.255 ± 0.015* (6.477 ± 0.381) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) ( +0.035 0.325 –0.015 8.255 +0.889 –0.381 ) 0.045 – 0.065 (1.143 – 1.651) 0.130 ± 0.005 (3.302 ± 0.127) 0.065 (1.651) TYP 0.100 (2.54) BSC 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 ± 0.003 (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) 10 LT1220 U PACKAGE DESCRIPTIO S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) 0.189 – 0.197* (4.801 – 5.004) 8 7 6 5 0.150 – 0.157** (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) SO8 1298 1 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 2 3 4 0.004 – 0.010 (0.101 – 0.254) 0.050 (1.270) BSC 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. 11 LT1220 U TYPICAL APPLICATIONS N DAC Current-to-Voltage Converter Cable Driver + VIN 75Ω DAC INPUTS 75Ω CABLE LT1220 VOUT – 75Ω 12 5pF 5k – 565A TYPE LT1220 V VOS + IOS (5kΩ) + OUT < 1/2LSB AVOL 1k VOUT + LT1220 • TA04 1k LT1220 • TA03 1MHz, 4th Order Butterworth Filter 909Ω 1.1k 47pF 22pF 909Ω 2.67k – VIN 1.1k 2.21k LT1220 220pF + – LT1220 470pF VOUT + LT1220 • TA05 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1221 150MHz, 250V/µs Amplifier AV ≥ 4 Version of the LT1220 LT1222 500MHz, 200V/µs Amplifier AV ≥ 10 Version of the LT1220 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com 1220fb LT/CP 0801 1.5K REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1991