LT1813

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400MHz, 2500V/ms, 9mA Single/Dual Operational Amplifiers n 400MHz Gain Bandwidth Product n 2500V/ms Slew Rate n –85dBc Distortion at 5MHz n 9mA Supply Current Per Amplifier n Space Saving SOT-23 and MS8 Packages n 6nV/ÖHz Input Noise Voltage n Unity-Gain Stable n 1.5mV Maximum Input Offset Voltage n 8mA Maximum Input Bias Current n 800nA Maximum Input Offset Current n 40mA Minimum Output Current, VOUT = –3V n –3.5V Minimum Input CMR, VS = –5V n Specified at –5V, Single 5V Supplies n Operating Temperature Range: – 40°C to 85°C n Wideband Amplifiers n Buffers n Active Filters n Video and RF Amplification n Communication Receivers n Cable Drivers n Data Acquisition Systems , LTC and LT are registered trademarks of Linear Technology Corporation. The LT 1818/LT1819 are single/dual wide bandwidth, high slew rate, low noise and distortion operational ampli- fiers with excellent DC performance. The LT1818/LT1819 have been designed for wider bandwidth and slew rate, much lower input offset voltage and lower noise and distortion than devices with comparable supply current. The circuit topology is a voltage feedback amplifier with the excellent slewing characteristics of a current feedback amplifier. The output drives a 100W load to –3.8V with –5V supplies. On a single 5V supply, the output swings from 1V to 4V with a 100W load connected to 2.5V. The amplifier is unity- gain stable with a 20pF capacitive load without the need for a series resistor. Harmonic distortion is –85dBc up to 5MHz for a 2V P-P output at a gain of 2. The LT1818/LT1819 are manufactured on Linear Technology’s advanced low voltage complementary bipo- lar process. The LT1818 (single op amp) is available in SOT-23 and SO-8 packages; the LT1819 (dual op amp) is available in MSOP-8 and SO-8 packages. LT1818 2.5VDC –1VAC

18189 TA01

2.5V 51.1Ω 5V 5V AIN+ LTC1744

14 BITS

(SET FOR 2VP-P FULL SCALE) AIN– Single Supply Unity-Gain ADC Driver for Oversampling Applications FREQUENCY (Hz) AMPLITUDE (dBc) –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110

18189 TA02

fIN = 5.102539MHz fS = 50Msps VIN = 300mVP-P SFDR = 78dB

8192 POINT FFT

FFT of Single Supply ADC Driver APPLICATIO SU

FEATURES

(Note 1) Differential Input Voltage Operating Temperature Range (Note 8) .. – 40°C to 85°C ABSOLUTE AXI U RATI GSW WW U PACKAGE/ORDER I FOR ATIOUU W *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for parts specified with wider operating temperature ranges. Specified Temperature Range (Note 9) ... –40°C to 85°C OUT A –IN A +IN A V V OUT B –IN B +IN B TOP VIEW MS8 PACKAGE 8-LEAD PLASTIC MSOP B A TOP VIEW S5 PACKAGE 5-LEAD PLASTIC SOT-23 OUT 1 V +IN –IN+– LTF7 S5 PART* MARKING ORDER PART NUMBER LT1818CS5 LT1818IS5 LTE7 LTE5 MS8 PART MARKING ORDER PART NUMBER TJMAX = 150°C, qJA = 250°C/W (NOTE 10) TJMAX = 150°C, qJA = 250°C/W (NOTE 10) LT1819CMS8 LT1819IMS8 TJMAX = 150°C, qJA = 150°C/W (NOTE 10) TOP VIEW NC OUT NC NC –IN +IN V S8 PACKAGE 8-LEAD PLASTIC SO LT1818CS8 LT1818IS8 ORDER PART NUMBER 1818 1818I S8 PART MARKING TJMAX = 150°C, qJA = 150°C/W (NOTE 10)

ELECTRICAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS VOS Input Offset Voltage (Note 4) 0.2 1.5 mV TA = 0°C to 70°C l 2.0 mV TA = –40°C to 85°C l 3.0 mV DVOS/DT Input Offset Voltage Drift T A = 0°C to 70°C (Note 7) l 10 15 mV/°C TA = –40°C to 85°C (Note 7) l 10 30 mV/°C IOS Input Offset Current 60 800 nA TA = 0°C to 70°C l 1000 nA TA = –40°C to 85°C l 1200 nA IB Input Bias Current –2 –8 mA TA = 0°C to 70°C l –10 mA TA = –40°C to 85°C l –12 mA en Input Noise Voltage Density f = 10kHz 6 nV/ ÖHz in Input Noise Current Density f = 10kHz 1.2 pA/ ÖHz The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 9) VS = –5V, VCM = 0V, unless otherwise noted. LT1819CS8 LT1819IS8 ORDER PART NUMBER 1819 1819I S8 PART MARKING TOP VIEW OUT B –IN B +IN B OUT A –IN A +IN A V S8 PACKAGE 8-LEAD PLASTIC SO A B

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS RIN Input Resistance V CM = V– + 1.5V to V+ – 1.5V 1.5 5 M W Differential 750 k W CIN Input Capacitance 1.5 pF VCM Input Voltage Range Guaranteed by CMRR –3.5 –4.2 V (Positive/Negative) T A = –40°C to 85°C l –3.5 V CMRR Common Mode Rejection Ratio V CM = –3.5V 75 85 dB TA = 0°C to 70°C l 73 dB TA = –40°C to 85°C l 72 dB Minimum Supply Voltage Guaranteed by PSRR –1.25 –2V TA = –40°C to 85°C l –2V PSRR Power Supply Rejection Ratio V S = –2V to –5.5V 78 97 dB TA = 0°C to 70°C l 76 dB TA = –40°C to 85°C l 75 dB AVOL Large-Signal Voltage Gain V OUT = –3V, RL = 500W 1.5 2.5 V/mV TA = 0°C to 70°C l 1.0 V/mV TA = –40°C to 85°C l 0.8 V/mV VOUT = –3V, RL = 100W 1.0 6 V/mV TA = 0°C to 70°C l 0.7 V/mV TA = –40°C to 85°C l 0.6 V/mV Channel Separation V OUT = –3V, LT1819 82 100 dB TA = 0°C to 70°C l 81 dB TA = –40°C to 85°C l 80 dB VOUT Output Swing(Positive/Negative) R L = 500W , 30mV Overdrive –3.8 –4.1 V TA = 0°C to 70°C l –3.7 V TA = –40°C to 85°C l –3.6 V RL = 100W , 30mV Overdrive –3.50 –3.8 V TA = 0°C to 70°C l –3.25 V TA = –40°C to 85°C l –3.15 V IOUT Output Current V OUT = –3V, 30mV Overdrive –40 –70 mA TA = 0°C to 70°C l –35 mA TA = –40°C to 85°C l –30 mA ISC Output Short-Circuit Current V OUT = 0V, 1V Overdrive (Note 3) –100 –200 mA TA = 0°C to 70°C l –90 mA TA = –40°C to 85°C l –70 mA SR Slew Rate A V = 1 2500 V/ ms AV = –1 (Note 5) 900 1800 V/ ms TA = 0°C to 70°C l 750 V/ ms TA = –40°C to 85°C l 600 V/ ms FPBW Full Power Bandwidth 6V P-P (Note 6) 95 MHz GBW Gain Bandwidth Product f = 4MHz, R L = 500W 270 400 MHz TA = 0°C to 70°C l 260 MHz TA = –40°C to 85°C l 250 MHz tr, tf Rise Time, Fall Time A V = 1, 10% to 90%, 0.1V Step 0.6 ns tPD Propagation Delay A V = 1, 50% to 50%, 0.1V Step 1.0 ns OS Overshoot A V = 1, 0.1V, RL = 100W 20 % tS Settling Time A V = –1, 0.1%, 5V 10 ns HD Harmonic Distortion HD2, A V = 2, f = 5MHz, VOUT = 2VP-P, RL = 500W –85 dBc HD3, AV = 2, f = 5MHz, VOUT = 2VP-P, RL = 500W –89 dBc dG Differential Gain A V = 2, RL = 150W 0.07 % dP Differential Phase A V = 2, RL = 150W 0.02 DEG IS Supply Current Per Amplifier 9 10 mA TA = 0°C to 70°C l 13 mA TA = –40°C to 85°C l 14 mA ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 9) VS = –5V, VCM = 0V, unless otherwise noted.

ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C (Note 9). VS = 5V, 0V; VCM = 2.5V, RL to 2.5V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS VOS Input Offset Voltage (Note 4) 0.4 2.0 mV TA = 0°C to 70°C l 2.5 mV TA = –40°C to 85°C l 3.5 mV DVOS/DT Input Offset Voltage Drift (Note 7) TA = 0°C to 70°C l 10 15 mV/°C TA = –40°C to 85°C l 10 30 mV/°C IOS Input Offset Current 60 800 nA TA = 0°C to 70°C l 1000 nA TA = –40°C to 85°C l 1200 nA IB Input Bias Current –2.4 –8 mA TA = 0°C to 70°C l –10 mA TA = –40°C to 85°C l –12 mA en Input Noise Voltage Density f = 10kHz 6 nV/ ÖHz in Input Noise Current Density f = 10kHz 1.4 pA/ ÖHz RIN Input Resistance V CM = V– + 1.5V to V+ – 1.5V 1.5 5 M W Differential 750 k W CIN Input Capacitance 1.5 pF VCM Input Voltage Range (Positive) Guaranteed by CMRR 3.5 4.2 V TA = –40°C to 85°C l 3.5 V Input Voltage Range (Negative) Guaranteed by CMRR 0.8 1.5 V TA = –40°C to 85°C l 1.5 V CMRR Common Mode Rejection Ratio V CM = 1.5V to 3.5V 73 82 dB TA = 0°C to 70°C l 71 dB TA = –40°C to 85°C l 70 dB Minimum Supply Voltage Guaranteed by PSRR –1.25 –2V TA = –40°C to 85°C l –2V PSRR Power Supply Rejection Ratio V S = 4V to 11V 78 97 dB TA = 0°C to 70°C l 76 dB TA = –40°C to 85°C l 75 dB AVOL Large-Signal Voltage Gain V OUT = 1.5V to 3.5V, RL = 500W 1.0 2 V/mV TA = 0°C to 70°C l 0.7 V/mV TA = –40°C to 85°C l 0.6 V/mV VOUT = 1.5V to 3.5V, RL = 100W 0.7 4 V/mV TA = 0°C to 70°C l 0.5 V/mV TA = –40°C to 85°C l 0.4 V/mV Channel Separation V OUT = 1.5V to 3.5V, LT1819 81 100 dB TA = 0°C to 70°C l 80 dB TA = –40°C to 85°C l 79 dB VOUT Output Swing(Positive) R L = 500W , 30mV Overdrive 3.9 4.2 V TA = 0°C to 70°C l 3.8 V TA = –40°C to 85°C l 3.7 V RL = 100W , 30mV Overdrive 3.7 4 V TA = 0°C to 70°C l 3.6 V TA = –40°C to 85°C l 3.5 V Output Swing(Negative) R L = 500W , 30mV Overdrive 0.8 1.1 V TA = 0°C to 70°C l 1.2 V TA = –40°C to 85°C l 1.3 V RL = 100W , 30mV Overdrive 1 1.3 V TA = 0°C to 70°C l 1.4 V TA = –40°C to 85°C l 1.5 V

ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C (Note 9). VS = 5V, 0V; VCM = 2.5V, RL to 2.5V unless otherwise noted. Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Differential inputs of –6V 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: With –5V supplies, slew rate is tested in a closed-loop gain of –1 by measuring the rise time of the output from –2V to 2V with an output step from –3V to 3V. With single 5V supplies, slew rate is tested in a closed-loop gain of –1 by measuring the rise time of the output from 1.5V to 3.5V with an output step from 1V to 4V. Falling edge slew rate is not production tested, but is designed, characterized and expected to be within 10% of the rising edge slew rate. Note 6: Full power bandwidth is calculated from the slew rate: FPBW = SR/2pV P Note 7: This parameter is not 100% tested. Note 8: The LT1818C/LT1818I and LT1819C/LT1819I are guaranteed functional over the operating temperature range of – 40°C to 85°C. Note 9: The LT1818C/LT1819C are guaranteed to meet specified performance from 0°C to 70°C and is designed, characterized and expected to meet the extended temperature limits, but is not tested at –40°C and 85°C. The LT1818I/LT1819I are guaranteed to meet the extended temperature limits. Note 10: Thermal resistance (q JA) varies with the amount of PC board metal connected to the package. The specified values are for short traces connected to the leads. If desired, the thermal resistance can be significantly reduced by connecting the V – pin to a large metal area. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS IOUT Output Current V OUT = 1.5V or 3.5V, 30mV Overdrive –30 –50 mA TA = 0°C to 70°C l –25 mA TA = –40°C to 85°C l –20 mA ISC Output Short-Circuit Current V OUT = 2.5V, 1V Overdrive (Note 3) –80 –140 mA TA = 0°C to 70°C l –70 mA TA = –40°C to 85°C l –50 mA SR Slew Rate A V = 1 1000 V/ ms AV = –1 (Note 5) 450 800 V/ ms TA = 0°C to 70°C l 375 V/ ms TA = –40°C to 85°C l 300 V/ ms FPBW Full Power Bandwidth 2V P-P (Note 6) 125 MHz GBW Gain Bandwidth Product f = 4MHz, R L = 500W 240 360 MHz TA = 0°C to 70°C l 230 MHz TA = –40°C to 85°C l 220 MHz tr, tf Rise Time, Fall Time A V = 1, 10% to 90%, 0.1V Step 0.7 ns tPD Propagation Delay A V = 1, 50% to 50%, 0.1V Step 1.1 ns OS Overshoot A V = 1, 0.1V, RL = 100W 20 % HD Harmonic Distortion HD2, A V = 2, f = 5MHz, VOUT = 2VP-P, RL = 500W –72 dBc HD3, AV = 2, f = 5MHz, VOUT = 2VP-P, RL = 500W –74 dBc dG Differential Gain A V = 2, RL = 150W 0.07 % dP Differential Phase A V = 2, RL = 150W 0.07 DEG IS Supply Current Per Amplifier 8.5 10 mA TA = 0°C to 70°C l 13 mA TA = –40°C to 85°C l 14 mA

TYPICAL PERFOR A CE CHARACTERISTICSUW Supply Current vs Temperature Input Common Mode Range vs Supply Voltage Input Bias Current vs Common Mode Voltage Input Noise Spectral Density Open-Loop Gain vs Resistive LoadInput Bias Current vs Temperature Output Voltage Swing vs Supply Voltage Output Voltage Swing vs Load CurrentOpen-Loop Gain vs Temperature TEMPERATURE (°C) –50 –25 SUPPLY CURRENT (mA) 0 50 75

18189 G01

VS = –5V VS = –2.5V PER AMPLIFIER SUPPLY VOLTAGE (– V) INPUT COMMON MODE RANGE (V) 1.0 1.5 2.0 – 2.0 –1.5 2 4 5

18189 G02

0.5 –1.0 – 0.5 1 3 6 7 TA = 25°C ∆VOS < 1mV INPUT COMMON MODE VOLTAGE (V) INPUT BIAS CURRENT (µA) TA = 25°C VS = – 5V

18189 G03

– 2.5 0 2.5 TEMPERATURE (°C) –50 –1.2 –0.8 25 75

18189 G04

–1.6 –2.0 –25 0 50 100 125 –2.4 –2.8 –0.4INPUT BIAS CURRENT (µA) VS = –5V VS = –2.5V VCM = 0V FREQUENCY (Hz) 10 100 in 100 0.1 1k 10k 100k

18189 G05

TA = 25°C VS = – 5V AV = 101 RS = 10k en INPUT VOLTAGE NOISE (nV/√Hz) INPUT CURRENT NOISE (pA/√Hz) LOAD RESISTANCE (Ω ) 100 OPEN-LOOP GAIN (dB) 1k 10k

18189 G06

TA = 25°C VS = – 5V VS = – 2.5V TEMPERATURE (°C) –50 OPEN-LOOP GAIN (dB) 25 75

18189 G07

–25 0 50 100 125 VS = – 5V VO = – 3V RL = 100Ω RL = 500Ω SUPPLY VOLTAGE (– V) OUTPUT VOLTAGE SWING (V)1.0 1.5 2.0 – 2.0 –1.5 2 4 5

18189 G08

0.5 –1.0 – 0.5 1 3 6 7 TA = 25°C ∆VOS = 30mV RL = 100Ω RL = 100Ω RL = 500Ω RL = 500Ω OUTPUT CURRENT (mA) –120 OUTPUT VOLTAGE SWING (V) OUTPUT VOLTAGE SWING (V)

18189 G09

–80 –40 0 80 120 TA = 25°C VS = –5V ∆VOS = 30mV SINK SOURCE

TYPICAL PERFOR A CE CHARACTERISTICSUW Output Current vs Temperature Output Impedance vs Frequency Output Short-Circuit Current vs Temperature Gain Bandwidth and Phase Margin vs TemperatureGain and Phase vs Frequency Gain vs Frequency, AV = 1 Gain vs Frequency, AV = 2 TEMPERATURE (°C) –50 OUTPUT SHORT-CIRCUIT CURRENT (mA) 160 200 240 25 75

18189 G10

–25 0 50 100 125 SOURCE SINK VS = – 5V VIN = –1V TEMPERATURE (˚C) –50 OUTUPT CURRENT (mA) 100 125 150 25 75

18189 G11

–25 0 50 100 125 ∆VOS = 30mV VOUT = –3V FOR VS = –5V VOUT = –1V FOR VS = –2.5V SOURCE, VS = –5V SINK, VS = –5V SOURCE, V S = –2.5V SINK, VS = –2.5V FREQUENCY (Hz) 10k 100k

0.01 OUTPUT IMPEDANCE (Ω )

0.1 100 1M 10M 100M

18189 G12

10 AV = 100

AV = 10 AV = 1 TA = 25°C VS = – 5V FREQUENCY (Hz) 10k 20GAIN (dB) PHASE (DEG) 100k 1M 500M 100M10M

18189 G13

–10 –20 100 120 140 –20 160 180 TA = 25°C AV = –1 RL = 500Ω GAINPHASE TEMPERATURE (°C) –50 –25 GAIN BANDWIDTH (MHz) PHASE MARGIN (DEG) 440 0 50 75

18189 G15

VS = – 5V GBW VS = –2.5V RL = 500Ω PHASE MARGIN VS = –2.5V PHASE MARGIN VS = –5V FREQUENCY (Hz) GAIN (dB) 10M 100M 500M

18189 G16

–10 TA = 25°C AV = 1 RL = 500Ω VS = –2.5V VS = –5V FREQUENCY (Hz) GAIN (dB) 10M 100M 300M

18189 G17

–10 TA = 25°C AV = 2 VS = –5V RF = RG = 500Ω CF = 1pF RL = 500Ω RL = 100Ω Gain vs Frequency, AV = – 1 FREQUENCY (Hz) GAIN (dB) 10M 100M 300M

18189 G18

–10 TA = 25°C AV = –1 RL = RF = RG = 500Ω VS = –2.5V VS = –5V

TYPICAL PERFOR A CE CHARACTERISTICSUW Slew Rate vs Input Step Slew Rate vs Supply Voltage Power Supply Rejection Ratio vs Frequency Common Mode Rejection Ratio vs Frequency FREQUENCY (Hz) 1k 10k 100k POWER SUPPLY REJECTION RATIO (dB) 1M 10M 100M

18189 G20

+PSRRPSRR TA = 25°C AV = 1 VS = –5V FREQUENCY (Hz) 1k 10k 100k COMMON MODE REJECTION RATIO (dB) 1M 10M 100M

18189 G21

TA = 25°C VS = –5VVS = –2.5V INPUT STEP (VP-P) SLEW RATE (V/µs) 800 2000 2 4 5

18189 G22

SR–SR+ TA =25°C AV = –1 VS = –5V RF = RG = RL = 500W SUPPLY VOLTAGE (–V) SLEW RATE (V/µs) 500 2 4 5

18189 G23

TA =25°C AV = –1 RF = RG = RL = 500W VIN = 6VP-P VIN = 2VP-P Gain Bandwidth and Phase Margin vs Supply Voltage SUPPLY VOLTAGE (–V) GAIN BANDWIDTH (MHz) PHASE MARGIN (DEG)

18189 G19

TA = 25°C GBW RL = 500Ω GBW RL = 100Ω PHASE MARGIN RL = 100Ω PHASE MARGIN RL = 500Ω Differential Gain and Phase vs Supply Voltage Slew Rate vs Temperature SUPPLY VOLTAGE (–V) DIFFERENTIAL PHASE (DEG) DIFFERENTIAL GAIN (%) 0.02 0.06 0.08 0.10 3 4

18189 G25

0.04 0.12 0.02 0.06 0.08 0.10 0.04 TA = 25°C 5 6 DIFFERENTIAL GAIN RL = 150Ω DIFFERENTIAL PHASE RL = 150Ω TEMPERATURE (°C) –50 SLEW RATE (V/µs)1600 2000 2400 25 75

18189 G24

–25 0 50 100 125 400 VS = –5V VS = –2.5V AV = –1 RF = RG = RL = 500Ω Distortion vs Frequency, AV = 2 Distortion vs Frequency, A V = –1 FREQUENCY (Hz) –60 –70 –80 –90 –100 –110 –120

18189 G27

DISTORTION (dB) 1M 10M2M 5M AV = –1 VS = –5V VO = 2VP-P 2ND, RL = 100 2ND, RL = 500 3RD, RL = 100 3RD, RL = 500 FREQUENCY (Hz) –60 –70 –80 –90 –100 –110 –120

18189 G26

DISTORTION (dB) 1M 10M2M 5M AV = 2 VS = –5V VO = 2VP-P 2ND, RL = 100 2ND, RL = 500 3RD, RL = 500 3RD, RL = 100

TYPICAL PERFOR A CE CHARACTERISTICSUW Distortion vs Frequency, AV = 1 FREQUENCY (Hz) –60 –70 –80 –90 –100 –110 –120

18189 G28

DISTORTION (dB) 1M 10M2M 5M AV = 1 VS = –5V VO = 2VP-P 3RD, RL = 100 2ND, RL = 100 3RD, RL = 500 2ND, RL = 500 Small-Signal Transient, 20dB Gain Large-Signal Transient, A V = –1 Large-Signal Transient, AV = 1 Large-Signal Transient, A V = –1 Channel Separation vs FrequencyDistortion vs Frequency, AV = 1 FREQUENCY (Hz) 10k CHANNEL SEPARATION (dB) 100k 1M 10M 100M 1G

18188 G29

TA = 25°C VS = –5V AV = –1 RF = RG = RL = 500Ω 0.1% Settling Time INPUT TRIGGER (1V/DIV) OUTPUT SETTLING RESIDUE (5mV/DIV) VS = –5V 5ns/DIV 18189 G30 VOUT = –2.5V SETTLING TIME = 9ns A V = –1 RF = RG = 500W CF = 4.1pF 2V/DIV VS = –5V 5ns/DIV 18189 G32 20mV/DIV 10ns/DIV 18189 G31 1V/DIV VS = –5V 10ns/DIV 18189 G34 1V/DIV VS = –5V 10ns/DIV 18189 G33

APPLICATIO S I FOR ATIOWU UU Layout and Passive Components As with all high speed amplifiers, the LT1818/LT1819 require some attention to board layout. A ground plane is recommended and trace lengths should be minimized, especially on the negative input lead. Low ESL/ESR bypass capacitors should be placed directly at the positive and negative supply (0.01mF ceramics are recommended). For high drive current applications, addi- tional 1mF to 10mF tantalums should be added. 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 500W are used, a parallel capacitor of value C F > RG • CIN/RF should be used to cancel the input pole and optimize dynamic performance (see Figure 1). For applications where the DC noise gain is 1 and a large feedback resistor is used, C F should be greater than or equal to C IN. An example would be an I-to-V converter. In high closed-loop gain configurations, RF >> RG, and no CF need to be added. To optimize the bandwidth in these applications, a capacitance, CG, may be added in parallel with RG in order to cancel out any parasitic CF capacitance. Capacitive Loading The LT1818/LT1819 are optimized for low distortion and high gain bandwidth applications. The amplifiers can drive a capacitive load of 20pF in a unity-gain configuration and more with higher gain. When driving a larger capacitive load, a resistor of 10W to 50W must be connected between the output and the capacitive load to avoid ringing or oscillation (see RS in Figure 1). The feedback must still be taken directly from the output so that the series resistor will isolate the capacitive load to ensure stability. Input Considerations The inputs of the LT1818/LT1819 amplifiers are con- nected to the bases of NPN and PNP bipolar transistors in parallel. The base currents are of opposite polarity and provide first order bias current cancellation. Due to variation in the matching of NPN and PNP beta, the polarity of the input bias current can be positive or negative. The offset current, however, does not depend on beta matching and is tightly controlled. Therefore, the use of balanced source resistance at each input is recom- mended for applications where DC accuracy must be maximized. For example, with a 100W source resistance at each input, the 800nA maximum offset current results in only 80mV of extra offset, while without balance the 8mA maximum input bias current could result in an 0.8mV offset condition. The inputs can withstand differential input voltages of up to 6V without damage and without needing clamping or series resistance for protection. This differential input voltage generates a large internal current (up to 50mA), which results in the high slew rate. In normal transient closed-loop operation, this does not increase power dis- sipation significantly because of the low duty cycle of the transient inputs. Sustained differential inputs, however, will result in excessive power dissipation and therefore this device should not be used as a comparator.

18189 F01

IN– IN+ CG Figure 1

APPLICATIO S I FOR ATIOWU UU Slew Rate The slew rate of the LT1818/LT1819 is proportional to the differential input voltage. Highest slew rates are therefore seen in the lowest gain configurations. For example, a 6V output step with a gain of 10 has a 0.6V input step, whereas at unity gain there is a 6V input step. The LT1818/LT1819 is tested for slew rate at a gain of –1. Lower slew rates occur in higher gain configurations, whereas the highest slew rate (2500V/ms) occurs in a noninverting unity-gain configuration. Power Dissipation The LT1818/LT1819 combine high speed and large output drive in small packages. It is possible to exceed the maximum junction temperature specification (150 °C) under certain conditions. Maximum junction temperature J) is calculated from the ambient temperature (T A), power dissipation per amplifier (PD) and number of ampli- fiers (n) as follows: TJ = TA + (n • PD • qJA) 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 the supply voltage). Therefore P DMAX is: PDMAX =( V+ – V–) • (ISMAX) + (V+/2)2/RL or PDMAX =( V+ – V–) • (ISMAX) + (V+ – VOMAX) • (VOMAX/RL) Example: LT1819IS8 at 85°C, VS = –5V, RL = 100W PDMAX = (10V) • (14mA) + (2.5V)2/100W = 202.5mW Circuit Operation The LT1818/LT1819 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. Complementary NPN and PNP emitter followers buffer the inputs and drive an internal resistor. The input voltage appears across the resistor, generating a current that is mirrored into the high impedance node. Complementary followers form an output stage that buffer the gain node from the load. The input resistor, input stage transconductance and the capacitor on the high imped- ance node determine the bandwidth. 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 step. Highest slew rates are therefore seen in the lowest gain configurations.

Single Supply Differential ADC Driver Results Obtained with the Circuit of Figure 2 at 5MHz. FFT Shows 81dB Overall Spurious Free Dynamic Range TYPICAL APPLICATIO U 1/2 LT1819 VIN

18189 TA05

51.1Ω AIN+ LTC1744 (SET FOR 2VP-P FULL SCALE)AIN– 18pF 51.1Ω 4.99k 0.1µF 18pF 10µF 4.99k 1/2 LT1819 536Ω 536Ω AMPLITUDE (dBc) –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 fIN = 5.023193MHz fS = 50Msps VIN = 750mVP-P

8192 SAMPLES

FREQUENCY (Hz)

18189 TA06

+IN –IN C (One Amplifier)SCHE ATIC WWSI PLIFIED UPACKAGE DESCRIPTIO 8-Lead Plastic MSOP (Reference LTC DWG # 05-08-1660) MSOP (MS8) 0802 0.53 – 0.015 (.021 – .006) SEATING PLANE NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 0.18 (.077) 0.254 (.010) 1.10 (.043) MAX 0.22 – 0.38 (.009 – .015) TYP 0.13 – 0.076 (.005 – .003) 0.86 (.034) REF 0.65 (.0256) BSC 0° – 6° TYP DETAIL “A” DETAIL “A” GAUGE PLANE 12 3 4 4.90 – 0.15 (1.93 – .006) 8 7 6 5 3.00 – 0.102 (.118 – .004) (NOTE 3) 3.00 – 0.102 (.118 – .004) NOTE 4 0.52 (.206) REF 5.23 (.206) MIN 3.2 – 3.45 (.126 – .136) 0.889 – 0.127 (.035 – .005) RECOMMENDED SOLDER PAD LAYOUT 0.42 – 0.04 (.0165 – .0015) TYP 0.65 (.0256) BSC

(Reference LTC DWG # 05-08-1633) UPACKAGE DESCRIPTIO 1.50 – 1.75 0.25 – 0.50 TYP 5 PLCS NOTE 3 DATUM ‘A’ 0.09 – 0.20 (NOTE 3) S5 SOT-23 0502 PIN ONE 2.80 – 3.10 (NOTE 4)

0.95 BSC

1.90 BSC

0.90 – 1.30 0.90 – 1.45 0.00 – 0.150.20 BSC 0.35 – 0.55 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ) ATTENTION: ORIGINAL SOT23-5L PACKAGE. MOST SOT23-5L PRODUCTS CONVERTED TO THIN SOT23 PACKAGE, DRAWING # 05-08-1635 AFTER APPROXIMATELY APRIL 2001 SHIP DATE

3.85 MAX

0.62 MAX 0.95 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 1.4 MIN2.62 REF

1.22 REF

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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .016 – .050 (0.406 – 1.270) .010 – .020 0°– 8° TYP .008 – .010 (0.203 – 0.254) SO8 0502 .053 – .069 (1.346 – 1.752) .014 – .019 (0.355 – 0.483) TYP .004 – .010 (0.101 – 0.254) .050 (1.270) BSC N 2 3 4 N/2 .150 – .157 (3.810 – 3.988) NOTE 3 8 7 6 5 .189 – .197 (4.801 – 5.004) NOTE 3 .228 – .244 (5.791 – 6.197) .245 MIN N 1 2 3 N/2 .160 –.005 RECOMMENDED SOLDER PAD LAYOUT .045 –.005 .050 BSC .030 –.005 TYP INCHES (MILLIMETERS) NOTE: 1. DIMENSIONS IN 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)

LT/TP 0103 2K • PRINTED IN USA ª LINEAR TECHNOLOGY CORPORATION 2002 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1395/LT1396/LT1397 Single/Dual/Quad 400MHz Current Feedback Amplifiers 4.6mA Supply Current LT1806/LT1807 Single/Dual 325MHz, 140V/m s Rail-to-Rail I/O Op Amps Low Noise: 3.5nV/ ÖHz LT1809/LT1810 Single/Dual 180MHz, 350V/m s Rail-to-Rail I/O Op Amps Low Distortion: –90dBc at 5MHz LT1812/LT1813/LT1814 Single/Dual/Quad 100MHz, 750V/ ms Op Amps Low Power: 3.6mA Max at –5V LT1815/LT1816/LT1817 Single/Dual/Quad 220MHz, 1500V/ ms Op Amps Programmable Supply Current LT6203/LT6204 Dual/Quad 100MHz, Rail-to-Rail I/O Op Amps 1.9nV/ÖHz Noise, 3mA Max Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 l FAX: (408) 434-0507 l www linear.com 1/2 LT1819 VIN VOUT

18189 TA03

200Ω 432Ω – 1/2 LT1819 200Ω –3dB BANDWIDTH: 80MHz 432Ω FREQUENCY (Hz) GAIN (dB) 100k 10M 100M

18189 TA04

–10 –5 VS = –5V TA = 25°C 80MHz, 20dB Gain Block 20dB Gain Block Frequency Response TYPICAL APPLICATIO U Large-Signal Transient Response 10ns/DIV 18189 TA07 1V/DIV