LT1353CS

LT1352/LT1353 Dual and Quad 250µA, 3MHz, 200V/µs Operational Amplifiers DESCRIPTIO The LT ®1352/LT1353 are dual and quad, very 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 combines the slewing performance of a current feedback amplifier in a true operational amplifier with matched high impedance inputs. The high slew rate ensures that the large-signal bandwidth is not degraded. Each output is capable of driving a 1kΩ load to ±13V with ±15V supplies and a 500Ω load to ±3.4V on ± 5V supplies. The LT1352/LT1353 are members of a family of fast, high performance amplifiers using this unique topology and employing Linear Technology Corporation’s advanced complementary bipolar processing. For higher bandwidth devices with higher supply current see the LT1354 through LT1365 data sheets. Bandwidths of 12MHz, 25MHz, 50MHz and 70MHz are available with 1mA, 2mA, 4mA and 6mA of supply current per amplifier. Singles, duals and quads of each amplifier are available. The LT1352 is available in an 8-lead SO package. The LT1353 is offered in a 14-lead narrow surface mount package. , LTC and LT are registered trademarks of Linear Technology Corporation. C-Load is a trademark of Linear Technology Corporation. FEATURES s s s s s s s s s s s s s s s s s 3MHz Gain Bandwidth 200V/µs Slew Rate 250µA Supply Current per Amplifier C-LoadTM Op Amp Drives All Capacitive Loads Unity-Gain Stable Maximum Input Offset Voltage: 600µV Maximum Input Bias Current: 50nA Maximum Input Offset Current: 15nA Minimum DC Gain, RL = 2k: 30V/mV Input Noise Voltage: 14nV/√Hz Settling Time to 0.1%, 10V Step: 700ns Settling Time to 0.01%, 10V Step: 1.25µs Minimum Output Swing into 1k: ± 13V Minimum Output Swing into 500Ω: ± 3.4V Specified at ± 2.5V, ± 5V and ± 15V Available in SO-8 Package LT1353 in Narrow Surface Mount Package APPLICATIO S s s s s s s Battery-Powered Systems Wideband Amplifiers Buffers Active Filters Data Acquisition Systems Photodiode Amplifiers TYPICAL APPLICATIO R1 50k R2 5k R5 1.1k R3 5k Instrumentation Amplifier R4 50k Large-Signal Response – 1/2 LT1352 – 1/2 LT1352 VOUT – VIN + + + 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 = 30kHz 1352/53 TA01 AV = – 1 U U U 1352/53 TA02 13523fa 1 LT1352/LT1353 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 ................ – 40°C to 85°C PACKAGE/ORDER INFORMATION TOP VIEW OUT A 1 –IN A 2 +IN A 3 V– 4 B A 6 5 –IN B +IN B 8 7 V+ OUT B ORDER PART NUMBER LT1352CN8 LT1352CS8 LT1352IN8 LT1352IS8 S8 PART MARKING 1352 1352I N8 PACKAGE 8-LEAD PDIP S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 130°C/ W (N8) TJMAX = 150°C, θJA = 190°C/ W (S8) Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS SYMBOL VOS PARAMETER Input Offset Voltage TA = 25°C, VCM = 0V unless otherwise noted VSUPPLY ± 15V ± 5V ± 2.5V ± 2.5V to ± 15V ± 2.5V to ± 15V MIN TYP 0.2 0.2 0.3 5 20 14 0.5 300 600 20 3 12.0 2.5 0.5 13.5 3.5 1.0 – 13.5 – 3.5 – 1.0 80 78 68 90 94 86 77 106 – 12.0 – 2.5 – 0.5 MAX 0.6 0.6 0.8 15 50 UNITS mV mV mV nA nA nV/√Hz pA/√Hz MΩ MΩ pF V V V V V V dB dB dB dB 13523fa CONDITIONS IOS IB en in RIN CIN Input Offset Current Input Bias Current Input Noise Voltage Input Noise Current Input Resistance Input Capacitance Positive Input Voltage Range f = 10kHz f = 10kHz VCM = ± 12V Differential Negative Input Voltage Range CMRR Common Mode Rejection Ratio VCM = ± 12V VCM = ± 2.5V VCM = ± 0.5V VS = ± 2.5V to ± 15V PSRR Power Supply Rejection Ratio 2 U U W WW U W Specified Temperature Range (Note 7) .. – 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 TOP VIEW OUT A 1 –IN A 2 +IN A 3 V+ 4 B C A D 14 OUT D 13 –IN D 12 +IN D 11 V – 10 +IN C 9 –IN C 8 OUT C ORDER PART NUMBER LT1353CS +IN B 5 –IN B 6 OUT B 7 S PACKAGE 14-LEAD PLASTIC SO TJMAX = 150°C, θJA = 150°C/ W ± 2.5V to ± 15V ± 2.5V to ± 15V ± 15V ± 15V ± 15V ± 15V ± 5V ± 2.5V ± 15V ± 5V ± 2.5V ± 15V ± 5V ± 2.5V LT1352/LT1353 ELECTRICAL CHARACTERISTICS SYMBOL AVOL PARAMETER Large-Signal Voltage Gain TA = 25°C, VCM = 0V unless otherwise noted VSUPPLY ± 15V ± 15V ± 15V ± 5V ± 5V ± 5V ± 2.5V ± 15V ± 15V ± 15V ± 5V ± 5V ± 2.5V ± 15V ± 5V ± 15V ± 15V ± 5V ± 15V ± 5V ± 15V ± 5V ± 2.5V ± 15V ± 5V ± 15V ± 5V ± 15V ± 5V ± 15V ± 15V ± 5V ± 5V ± 15V ± 15V ± 15V ± 5V 101 2.0 1.8 MIN 40 30 20 30 25 15 20 13.5 13.4 13.0 3.5 3.4 1.3 13.0 6.8 30 120 30 TYP 80 60 40 60 50 30 40 14.0 13.8 13.4 4.0 3.8 1.7 13.4 7.6 45 200 50 3.2 2.6 3.0 2.7 2.5 46 53 13 16 41 52 700 1250 950 1400 1.5 120 250 230 320 300 MAX UNITS V/mV V/mV V/mV V/mV V/mV V/mV V/mV ±V ±V ±V ±V ±V ±V mA mA mA V/µs V/µs MHz MHz MHz MHz MHz ns ns % % ns ns ns ns ns ns Ω dB µA µA CONDITIONS VOUT = ± 12V, RL = 5k VOUT = ± 10V, RL = 2k VOUT = ± 10V, RL = 1k VOUT = ± 2.5V, RL = 5k VOUT = ± 2 .5V, RL = 2k VOUT = ± 2.5V, RL = 1k VOUT = ± 1V, RL = 5k RL = 5k, VIN = ±10mV RL = 2k, VIN = ±10mV RL = 1k, VIN = ±10mV RL = 1k, VIN = ±10mV RL= 500Ω, VIN = ±10mV RL = 5k, VIN = ±10mV VOUT = ± 13V VOUT = ± 3.4V VOUT = 0V, VIN = ± 3V AV = – 1, RL = 5k (Note 4) 10V Peak (Note 5) 3V Peak (Note 5) f = 200kHz, RL = 10k VOUT Output Swing IOUT ISC SR Output Current Short-Circuit Current Slew Rate Full-Power Bandwidth GBW Gain Bandwidth tr, tf Rise Time, Fall Time Overshoot Propagation Delay AV = 1, 10% to 90%, 0.1V AV = 1, 0.1V 50% VIN to 50% VOUT, 0.1V 10V Step, 0.1%, AV = – 1 10V Step, 0.01%, AV = – 1 5V Step, 0.1%, AV = – 1 5V Step, 0.01%, AV = – 1 AV = 1, f = 20kHz VOUT = ±10V, RL = 2k Each Amplifier Each Amplifier ts Settling Time RO IS Output Resistance Channel Separation Supply Current 0°C ≤ TA ≤ 70°C, VCM = 0V unless otherwise noted SYMBOL VOS PARAMETER Input Offset Voltage CONDITIONS VSUPPLY ± 15V ± 5V ± 2.5V (Note 6) ± 2.5V to ± 15V ± 2.5V to ± 15V ± 2.5V to ± 15V 3 MIN TYP MAX 0.8 0.8 1.0 8 20 75 UNITS mV mV mV µV/ °C nA nA 13523fa Input VOS Drift IOS IB Input Offset Current Input Bias Current 3 LT1352/LT1353 ELECTRICAL CHARACTERISTICS SYMBOL CMRR PARAMETER Common Mode Rejection Ratio 0°C ≤ TA ≤ 70°C, VCM = 0V unless otherwise noted VSUPPLY ± 15V ± 5V ± 2.5V ± 15V ± 15V ± 5V ± 5V ± 5V ± 2.5V ± 15V ± 15V ± 15V ± 5V ± 5V ± 2.5V ± 15V ± 5V ± 15V ± 15V ± 5V ± 15V ± 5V ± 15V ± 15V ± 5V MIN 78 77 67 89 25 20 20 15 10 15 13.4 13.3 12.0 3.4 3.3 1.2 12.0 6.6 24 100 21 1.8 1.6 100 350 330 TYP MAX UNITS dB dB dB dB V/mV V/mV V/mV V/mV V/mV V/mV ±V ±V ±V ±V ±V ±V mA mA mA V/µs V/µs MHz MHz dB µA µA CONDITIONS VCM = ± 12V VCM = ± 2.5V VCM = ± 0.5V VS = ± 2.5V to ± 15V VOUT = ± 12V, RL = 5k VOUT = ± 10V, RL = 2k VOUT = ± 2.5V, RL = 5k VOUT = ± 2 .5V, RL = 2k VOUT = ± 2.5V, RL = 1k VOUT = ± 1V, RL = 5k RL = 5k, VIN = ±10mV RL = 2k, VIN = ±10mV RL = 1k, VIN = ±10mV RL = 1k, VIN = ±10mV RL= 500Ω, VIN = ±10mV RL = 5k, VIN = ±10mV VOUT = ± 12V VOUT = ± 3.3V VOUT = 0V, VIN = ± 3V AV = – 1, RL = 5k (Note 4) f = 200kHz, RL = 10k VOUT = ±10V, RL = 2k Each Amplifier Each Amplifier PSRR AVOL Power Supply Rejection Ratio Large-Signal Voltage Gain VOUT Output Swing IOUT ISC SR GBW Output Current Short-Circuit Current Slew Rate Gain Bandwidth Channel Separation IS Supply Current – 40°C ≤ TA ≤ 85°C, VCM = 0V unless otherwise noted (Note 7) SYMBOL VOS PARAMETER Input Offset Voltage CONDITIONS VSUPPLY ± 15V ± 5V ± 2.5V (Note 6) ± 2.5V to ± 15V ± 2.5V to ± 15V ± 2.5V to ± 15V VCM = ± 12V VCM = ± 2.5V VCM = ± 0.5V VS = ± 2.5V to ± 15V VOUT = ± 12V, RL = 5k VOUT = ± 10V, RL = 2k VOUT = ± 2.5V, RL = 5k VOUT = ± 2 .5V, RL = 2k VOUT = ± 2.5V, RL = 1k VOUT = ± 1V, RL = 5k ± 15V ± 15V ± 5V ± 5V ± 5V ± 2.5V ± 15V ± 5V ± 2.5V 76 76 66 87 20 15 15 10 8 10 3 MIN TYP MAX 1.0 1.0 1.2 8 50 100 UNITS mV mV mV µV/ °C nA nA dB dB dB dB V/mV V/mV V/mV V/mV V/mV V/mV Input VOS Drift IOS IB CMRR Input Offset Current Input Bias Current Common Mode Rejection Ratio PSRR AVOL Power Supply Rejection Ratio Large-Signal Voltage Gain 13523fa 4 LT1352/LT1353 ELECTRICAL CHARACTERISTICS SYMBOL VOUT PARAMETER Output Swing – 40°C ≤ TA ≤ 85°C, VCM = 0V unless otherwise noted (Note 7) VSUPPLY ± 15V ± 15V ± 15V ± 5V ± 5V ± 2.5V ± 15V ± 5V ± 15V ± 15V ± 5V ± 15V ± 5V ± 15V ± 15V ± 5V MIN 13.3 13.2 10.0 3.3 3.2 1.1 10.0 6.4 20 50 15 1.6 1.4 99 380 350 TYP MAX UNITS ±V ±V ±V ±V ±V ±V mA mA mA V/µs V/µs MHz MHz dB µA µA CONDITIONS RL = 5k, VIN = ±10mV RL = 2k, VIN = ±10mV RL = 1k, VIN = ±10mV RL = 1k, VIN = ±10mV RL= 500Ω, VIN = ±10mV RL = 5k, VIN = ±10mV VOUT = ± 10V VOUT = ± 3.2V VOUT = 0V, VIN = ± 3V AV = – 1, RL = 5k (Note 4) f = 200kHz, RL = 10k VOUT = ±10V, RL = 2k Each Amplifier Each Amplifier IOUT ISC SR GBW Output Current Short-Circuit Current Slew Rate Gain Bandwidth Channel Separation IS Supply Current 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: Slew rate is measured between ± 8V on the output with ± 12V input for ± 15V supplies and ± 2V on the output with ± 3V input for ± 5V supplies. Note 5: Full-power bandwidth is calculated from the slew rate measurement: FPBW = (Slew Rate)/2πVP. Note 6: This parameter is not 100% tested. Note 7: The LT1352C/LT1353C are guaranteed to meet specified performance from 0°C to 70°C. The LT1352C/LT1353C 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. The LT1352I/LT1353I are guaranteed to meet specified performance from – 40°C to 85°C. TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Supply Voltage and Temperature 350 V+ – 0.5 TA = 25°C ∆VOS = 1mV INPUT BIAS CURRENT (nA) SUPPLY CURRENT PER AMPLIFIER (µA) COMMON MODE RANGE (V) 300 125°C 250 25°C 200 – 55°C 150 100 0 10 5 15 SUPPLY VOLTAGE (± V) UW 1352/53 G01 Input Common Mode Range vs Supply Voltage 30 Input Bias Current vs Input Common Mode Voltage TA = 25°C VS = ±15V 20 IB = IB+ + IB– 2 –1.0 –1.5 –2.0 10 2.0 1.5 1.0 0.5 V– 0 –10 20 0 15 10 5 SUPPLY VOLTAGE (± V) 20 1352/53 G02 –20 –15 10 –5 0 5 –10 INPUT COMMON MODE VOLTAGE (V) 15 1352/53 G03 13523fa 5 LT1352/LT1353 TYPICAL PERFORMANCE CHARACTERISTICS Input Bias Current vs Temperature 40 36 VS = ±15V IB+ + IB– IB = 2 INPUT BIAS CURRENT (nA) 32 28 24 20 16 12 8 4 INPUT VOLTAGE NOISE (nV/√Hz) OPEN-LOOP GAIN (dB) 0 –50 –25 50 25 0 75 TEMPERATURE (°C) Open-Loop Gain vs Temperature 100 99 VS = ±15V VO = ±12V RL = 5k OUTPUT VOLTAGE SWING (V) OUTPUT VOLTAGE SWING (V) OPEN-LOOP GAIN (dB) 98 97 96 95 94 –50 –25 50 25 75 0 TEMPERATURE (°C) Output Short-Circuit Current vs Temperature 60 OUTPUT SHORT-CIRCUIT CURRENT (mA) 55 VS = ±15V OUTPUT STEP (V) OUTPUT STEP (V) 50 SINK 45 40 35 30 25 –50 –25 SOURCE 50 25 75 0 TEMPERATURE (°C) 6 UW 100 1352/53 G04 Input Noise Spectral Density 100 TA = 25°C VS = ±15V AV = 101 RS = 100k en 10 in 1 10 INPUT CURRENT NOISE (pA/√Hz) Open-Loop Gain vs Resistive Load 110 TA = 25°C VS = ±15V VS = ± 5V 90 100 80 70 125 1 1 10 1k 100 FREQUENCY (Hz) 0.1 10k 1352/53 G05 60 10 100 1k 10k 1352/53 G06 LOAD RESISTANCE (Ω) Output Voltage Swing vs Supply Voltage V+ –1 –2 –3 3 2 1 V– 0 5 15 SUPPLY VOLTAGE (V) 10 20 1352/53 G08 Output Voltage Swing vs Load Current V+ RL = 2k RL = 1k – 0.5 –1.0 –1.5 –2.0 25°C 85°C – 40°C – 40°C 25°C 85°C 15 20 VS = ± 5V VIN = 10mV 25°C 85°C – 40°C 25°C – 40°C 85°C TA = 25°C VIN = ±10mV RL = 1k RL = 2k 2.0 1.5 1.0 0.5 100 125 V– –20 –15 –10 – 5 0 10 5 OUTPUT CURRENT (mA) 1352/53 G07 1352/53 G09 Settling Time vs Output Step (Noninverting) 10 8 6 10mV 4 2 0 –2 –4 –6 –8 –10 100 125 10 8 Settling Time vs Output Step (Inverting) 1mV 6 4 2 0 –2 –4 –6 –8 10mV VS = ±15V AV = –1 RG = RF = 2k CF = 5pF RL = 2k 1mV 10mV 1mV 10mV 1mV VS = ±15V AV = 1 OUTPUT FILTER: 1.6MHz LPF 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6 SETTLING TIME (µs) 1352/53 G11 –10 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 SETTLING TIME (µs) 1352/53 G12 1352/53 G10 13523fa LT1352/LT1353 TYPICAL PERFORMANCE CHARACTERISTICS Gain and Phase vs Frequency 70 60 50 PHASE VS = ±15V VS = ± 5V GAIN 20 10 0 –10 1k 10k 100k 1M FREQUENCY (Hz) 10M 20 0 –20 –40 100M VS = ± 5V TA = 25°C AV = –1 RF = RG = 5k VS = ±15V 120 100 OUTPUT IMPEDANCE (Ω) GAIN (dB) GAIN (dB) 40 30 Gain Bandwidth and Phase Margin vs Temperature 4.50 4.25 4.00 VS = ±15V VS = ± 5V PHASE MARGIN 50 48 46 GAIN BANDWIDTH (MHz) 3.75 3.50 3.25 3.00 2.75 2.50 2.25 2.00 –50 –25 GAIN (dB) GAIN (dB) GAIN BANDWIDTH VS = ±15V VS = ± 5V 50 25 0 75 TEMPERATURE (°C) Gain Bandwidth and Phase Margin vs Supply Voltage 4.50 4.25 4.00 GAIN BANDWIDTH (MHz) 3.75 3.50 3.25 3.00 2.75 2.50 2.25 2.00 0 15 10 5 SUPPLY VOLTAGE (± V) 20 1352/53 G19 POWER SUPPLY REJECTION RATIO (dB) 48 46 PHASE MARGIN PHASE MARGIN (DEG) 44 42 40 38 36 GAIN BANDWIDTH 34 32 30 100 80 COMMON MODE REJECTION RATIO (dB) TA = 25°C UW 1352/53 G13 Output Impedance vs Frequency 1000 TA = 25°C VS = ±15V AV = 100 AV = 10 10 AV = 1 10 8 6 4 2 0 –2 –4 0.1 –6 –8 0.01 1k 10k 100k 1M FREQUENCY (Hz) 10M 1352/53 G14 Frequency Response vs Capacitive Load TA = 25°C VS = ±15V AV = – 1 RFB = RG = 5k 100 80 60 40 C = 5000pF C = 1000pF C = 500pF C = 100pF PHASE (DEG) 1 C = 10pF –10 10k 100k 1M FREQUENCY (Hz) 10M 1352/53 G15 Frequency Response vs Supply Voltage (AV = 1) 5 4 3 PHASE MARGIN (DEG) 2 1 0 –1 –2 –3 –4 –5 10k 100k 1M FREQUENCY (Hz) 10M 1352/53 G17 Frequency Response vs Supply Voltage (AV = – 1) 5 4 3 2 1 0 –1 –2 –3 –4 –5 10k ±15V ±5V ± 2.5V 100k 1M FREQUENCY (Hz) 10M 1352/53 G18 TA = 25°C AV = 1 RL = 5k TA = 25°C AV = – 1 RF = RG = 5k 44 42 40 38 36 34 32 100 30 125 ±15V ±5V ± 2.5V 1352/53 G16 Power Supply Rejection Ratio vs Frequency 50 120 TA = 25°C VS = ±15V 120 100 80 60 40 20 Common Mode Rejection Ratio vs Frequency TA = 25°C VS = ±15V – PSRR = +PSRR 60 40 20 0 10 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 0 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1352/53 G20 1352/53 G21 13523fa 7 LT1352/LT1353 TYPICAL PERFORMANCE CHARACTERISTICS Slew Rate vs Supply Voltage 200 TA = 25°C AV = –1 RF = RG = 5k SR = (SR+ + SR – )/2 SLEW RATE (V/µs) 150 SLEW RATE (V/µs) SLEW RATE (V/µs) 100 50 50 0 0 5 10 SUPPLY VOLTAGE (± V) 15 1352/53 G22 Total Harmonic Distortion vs Frequency 1 TOTAL HARMONIC DISTORTION (%) TA = 25°C VS = ±15V RL = 5k VO = 2VP-P 30 OUTPUT VOLTAGE (VP-P) OUTPUT VOLTAGE (VP-P) 0.1 0.01 AV = –1 0.001 10 AV = 1 100 1k 10k FREQUENCY (Hz) 100k 1352/53 G25 2nd and 3rd Harmonic Distortion vs Frequency – 30 – 40 – 50 3RD HARMONIC – 60 –70 2ND HARMONIC – 80 VS = ±15V AV = 1 RL = 5k VO = 2VP-P CROSSTALK (dB) HARMONIC DISTORTION (dB) OVERSHOOT (%) – 90 100k FREQUENCY (Hz) 8 UW 1352/53 G28 Slew Rate vs Temperature 250 AV = –1 RF = RG = RL = 5k SR = (SR+ + SR – )/2 VS = ±15V 150 Slew Rate vs Input Level 200 175 150 125 100 75 50 25 TA = 25°C VS = ±15V AV = –1 RFB = RG = 5k SR = (SR+ + SR –)/2 200 100 VS = ± 5V 0 –50 –25 50 0 75 25 TEMPERATURE (°C) 100 125 0 0 4 8 16 12 INPUT LEVEL (VP-P) 20 24 1352/53 G23 1352/53 G24 Undistorted Output Swing vs Frequency (± 15V) 10 AV = –1 25 AV = 1 20 15 10 5 VS = ±15V RL = 5k THD = 1% 100k FREQUENCY (Hz) 1M 1352/53 G26 Undistorted Output Swing vs Frequency (± 5V) 9 8 7 6 5 4 3 2 1 VS = ± 5V RL = 5k THD = 1% 100k FREQUENCY (Hz) 1M 1352/53 G27 AV = 1 AV = –1 0 10k 0 10k Crosstalk vs Frequency – 40 – 50 – 60 –70 – 80 – 90 TA = 25°C AV = 1 RL = 1k VIN = 15dBm 100 90 80 70 60 50 40 30 20 10 Capacitive Load Handling TA = 25°C VS = ±15V RL = 5k AV = 1 AV = – 1 –100 –110 1M –120 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1352/53 G29 0 10p 100p 1n 10n 0.1µ CAPACITIVE LOAD (F) 1µ 1352/53 G30 13523fa LT1352/LT1353 TYPICAL PERFORMANCE CHARACTERISTICS Small-Signal Transient (AV = 1) Small-Signal Transient (AV = – 1) Small-Signal Transient (AV = – 1, CL = 1000pF) Large-Signal Transient (AV = 1) APPLICATIONS INFORMATION Layout and Passive Components The LT1352/LT1353 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 can combine with the input capacitance to form a pole which can cause peaking or even oscillations. If feedback resistors greater than 10k are used, a parallel capacitor of value, C F > (RG)(CIN/RF), should be used to cancel the input pole and optimize dynamic performance. For applications where the DC noise gain is one 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 as shown in the Typical Applications section. Capacitive Loading The LT1352/LT1353 are stable with any capacitive load. 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. Graphs of Frequency Response vs Capacitive Load, Capacitive Load Handling and the transient response photos clearly show these effects. Input Considerations Each of the LT1352/LT1353 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 13523fa U W UW 1352/53 G31 1352/53 G34 1352/53 G32 1352/53 G33 Large-Signal Transient (AV = – 1) Large-Signal Transient (AV = 1, CL = 10,000pF) 1352/53 G35 1352/53 G36 U U 9 LT1352/LT1353 APPLICATIONS INFORMATION applications where DC accuracy must be maximized. 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 application 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 time that the inputs are apart. Measure the average supply current for the application in order to calculate the power dissipation. Circuit Operation The LT1352/LT1353 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 R1, a 1k resistor. The input voltage appears across the resistor generating currents which are mirrored into the high impedance node and compensation capacitor CT. Complementary followers form an output stage which buffers the gain node from the load. The output devices Q19 and Q22 are connected to form a composite PNP and a composite NPN. 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 high impedance 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 whereas the same output step in unity gain has a 10 times greater input step. The graph Slew Rate vs Input Level illustrates this relationship. In higher gain configurations the largesignal performance and the small-signal performance both look like a single pole response. Capacitive load compensation is provided by the RC, CC network which is bootstrapped across the output stage. When the amplifier is driving a light load the network has no effect. 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 and a zero is created by the RC combination, both of which improve the phase margin. The design ensures 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 LT1352/LT1353 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 of 150°C under certain conditions. Maximum junction temperature TJ is calculated from the ambient temperature TA and power dissipation PD as follows: LT1352CN8: TJ = TA + (PD)(130°C/W) LT1352CS8: TJ = TA + (PD)(190°C/W) LT1353CS: TJ = TA + (PD)(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 PD(MAX) is: PD(MAX) = (V + – V –)(IS(MAX)) + (V +/2)2/RL or (V + – V –)(IS(MAX)) + (V + – VMAX)(IMAX) Example: LT1353 in S14 at 85°C, VS = ±15V, RL = 500Ω, VOUT = ± 5V (±10mA) PD(MAX) = (30V)(380µA) + (15V – 5V)(10mA) = 111mW TJ = 85°C + (4)(111mW)(150°C/W) = 152°C 10 U W U U 13523fa LT1352/LT1353 SI PLIFIED SCHE ATIC V+ R2 Q10 Q11 Q12 Q20 R3 Q21 –IN Q5 Q6 Q8 Q4 V– W W C1 R6 Q9 Q7 R1 Q3 1k Q2 Q17 Q1 +IN Q18 R7 Q13 CT Q15 RC CC Q19 OUTPUT Q22 C2 Q14 Q16 Q23 R4 Q24 R5 1352/53 SS 13523fa 11 LT1352/LT1353 TYPICAL APPLICATIONS DAC I-to-V Converter 10pF DAC INPUTS 12 5k V VOS + IOS (5kΩ) + OUT < 0.5LSB AVOL 1/2 LT1352 10nF 12 – + U – 1/2 LT1352 VOUT 565A TYPE 5k + 1352/53 TA03 400kHz Photodiode Preamp with 10kHz Highpass Loop 1N5712 10k – BPV22NF 1.5k 1/2 LT1352 VOUT 10k + 10nF 10k 1352/53 TA05 13523fa LT1352/LT1353 PACKAGE DESCRIPTION N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .400* (10.160) MAX 8 7 6 5 .300 – .325 (7.620 – 8.255) .008 – .015 (0.203 – 0.381) ( +.035 .325 –.015 8.255 +0.889 –0.381 ) INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) NOTE: 1. DIMENSIONS ARE U .255 ± .015* (6.477 ± 0.381) 1 2 3 4 .130 ± .005 (3.302 ± 0.127) .045 – .065 (1.143 – 1.651) .065 (1.651) TYP .120 (3.048) .020 MIN (0.508) MIN .018 ± .003 (0.457 ± 0.076) N8 1002 .100 (2.54) BSC 13523fa 13 LT1352/LT1353 PACKAGE DESCRIPTION S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .189 – .197 (4.801 – 5.004) NOTE 3 8 7 6 5 .050 BSC .245 MIN .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) 0°– 8° TYP .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 14 U .045 ±.005 .160 ±.005 .228 – .244 (5.791 – 6.197) .150 – .157 (3.810 – 3.988) NOTE 3 1 2 3 4 .053 – .069 (1.346 – 1.752) .004 – .010 (0.101 – 0.254) .014 – .019 (0.355 – 0.483) TYP .050 (1.270) BSC SO8 0303 13523fa LT1352/LT1353 PACKAGE DESCRIPTION S Package 14-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .337 – .344 (8.560 – 8.738) NOTE 3 14 13 12 11 10 9 8 .050 BSC N .245 MIN 1 .030 ±.005 TYP 2 3 RECOMMENDED SOLDER PAD LAYOUT 1 .010 – .020 × 45° (0.254 – 0.508) 2 3 4 5 6 7 .008 – .010 (0.203 – 0.254) .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 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 .045 ±.005 N .160 ±.005 .228 – .244 (5.791 – 6.197) N/2 N/2 .150 – .157 (3.810 – 3.988) NOTE 3 .053 – .069 (1.346 – 1.752) 0° – 8° TYP .004 – .010 (0.101 – 0.254) .014 – .019 (0.355 – 0.483) TYP .050 (1.270) BSC S14 0502 13523fa 15 LT1352/LT1353 TYPICAL APPLICATIONS 20kHz, 4th Order Butterworth Filter 4.64k 470pF 5.49k 220pF 4.64k VIN 2200pF 13.3k RELATED PARTS PART NUMBER LT1351 LT1354/55/56 DESCRIPTION 250µA, 3MHz, 200V/µs Op Amp Single/Dual/Quad 1mA, 12MHz, 400V/µs Op Amp COMMENTS Good DC Precision, C-Load Stable, Power Saving Shutdown Good DC Precision, Stable with All Capacitive Loads 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 q FAX: (408) 434-0507 q U – 1/2 LT1352 5.49k 11.3k – 1/2 LT1352 VOUT + 4700pF + 1352/53 TA04 13523fa LT/TP 0603 1K REV A • PRINTED IN USA www.linear.com © LINEAR TECHNOLOGY CORPORATION 1996