LT1797 10MHz, Rail-to-Rail Input and Output Op Amp in SOT-23 DESCRIPTION FEATURES n n n n n n n n n n n n n n Rail-to-Rail Input and Output Small SOT-23 Package Gain Bandwidth Product: 10MHz –40°C to 85°C Operation Slew Rate: 2.25V/μs Low Input Offset Voltage: 1.5mV Max High Output Current: 25mA Min Specified on 3V, 5V and ±5V Supplies High Voltage Gain: 1000V/mV 10k Load High CMRR: 96dB Typ High PSRR: 90dB Typ Input Bias Current: 300nA Max Input Offset Current: 25nA Max Low Profile (1mm) SOT-23 (ThinSOT™) Package The LT®1797 is a unity-gain stable 10MHz op amp available in the small SOT-23 package that operates on all single and split supplies with a total voltage of 2.7V to 12V. The amplifier draws 1mA of quiescent current and has a slew rate of 2.25V/μs. The input common mode range of the LT1797 includes both rails, making it ideal for current sensing applications. The input stage incorporates phase reversal protection to prevent false outputs from occurring when the inputs are driven beyond the supplies. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced above or below the supplies. The output of the LT1797 can swing to within 50mV of V+ and 8mV of V– without drawing excess current in either condition. The amplifier can drive loads up to 25mA and still maintain rail-to-rail capability. APPLICATIONS n n n n n Portable Instrumentation Rail-to-Rail Buffer Amplifiers Low Voltage Signal Processing Driving A/D Converters Battery-Powered Systems The LT1797 op amp is available in the space saving 5-lead SOT-23 package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and ThinSOT and Over-The-Top are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION Fast Compact –48V Current Sense Small-Signal Response VOUT = 3V – 0.1Ω • ISENSE ISENSE = 0A TO 30A ACCURACY ≈ 3% VOUT Q1 FMMT493 30.1Ω 1% – 3.3k 0805 s3 + R1 4.7k 1k 1% VS = 3V R1 REDUCES Q1 DISSIPATION LT1797 0.1μF BZX84C6V8 VZ = 6.8V –48V SUPPLY (–42V TO –56V) 1797 TA01b SETTLES TO 1% IN 2μs, 1V OUTPUT STEP 0.003Ω 1% 3W – ISENSE + 1797 TA01 VS = ±2.5V AV = 1 RL = 10k –48V LOAD 1797fb 1 LT1797 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) Total Supply Voltage (V+ to V–) .............................. 12.6V Input Differential Voltage ....................................... 12.6V Input Current........................................................ ±10mA Output Short-Circuit Duration (Note 2) ........ Continuous Operating Temperature Range (Note 3) ...–40°C to 85°C Specified Temperature Range ..................–40°C to 85°C Junction Temperature ........................................... 150°C Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, 10 sec)................... 300°C TOP VIEW 5 V+ OUT 1 V– 2 + – +IN 3 4 –IN S5 PACKAGE 5-LEAD PLASTIC TSOT-23 TJMAX = 150°C, θJA = 250°C/W ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT1797CS5#PBF LT1797CS5#TRPBF LTLM 5-Lead Plastic TSOT-23 –40°C to 85°C LT1797IS5#PBF LT1797IS5#TRPBF LTTL 5-Lead Plastic TSOT-23 –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V, VCM = VOUT = half supply, pulse power tested, unless otherwise specified. (Note 3) SYMBOL PARAMETER VOS Input Offset Voltage CONDITIONS 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C Input Bias Current l l l Input Offset Voltage Drift (Note 4) IB MIN VCM = V– VCM = V+ Input Bias Current Drift l l –300 TYP MAX 1 1.5 2.5 3.0 mV mV mV 5 20 μV/°C –150 50 100 nA nA l 0.1 l l 10 10 UNITS nA/°C IOS Input Offset Current VCM = V– VCM = V+ Input Noise Voltage 0.1Hz to 10Hz 1.5 μVP-P en Input Noise Voltage Density f = 10kHz 20 nV/√Hz in Input Noise Current Density f = 10kHz f = 10kHz, VCM = VCC – 0.3V 0.23 0.15 pA/√Hz pA/√Hz RIN Input Resistance Differential Common Mode, VCM = 0V to VS – 1.3V 330 100 kΩ MΩ CIN Input Capacitance 4 pF CMRR Common Mode Rejection Ratio 96 72 68 dB dB dB VCM = 0V to VS – 1.3V VS = 5V, VCM = 0V to 5V VS = 3V, VCM = 0V to 3V 200 l l l 82 64 60 25 25 nA nA 1797fb 2 LT1797 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 3V, 0V; VS = 5V, 0V, VCM = VOUT = half supply, pulse power tested, unless otherwise specified. (Note 3) SYMBOL PARAMETER CONDITIONS Input Voltage Range AVOL Large-Signal Voltage Gain VS = 3V, VO = 0.5V to 2.5V, RL = 10k VS = 5V, VO = 0.5V to 4.5V, RL = 10k PSRR Power Supply Rejection Ratio VS = 2.7V to 12V, VCM = VO = 1V MIN TYP MAX UNITS l 0 l 200 150 1000 V/mV V/mV l 400 300 1000 V/mV V/mV l 80 90 VS V dB l 2.5 2.7 V VOL Output Voltage Swing LOW No Load, Input Overdrive = 30mV ISINK = 5mA ISINK = 10mA l l l 8 80 150 30 160 250 mV mV mV VOH Output Voltage Swing HIGH No Load, Input Overdrive = 30mV ISOURCE = 5mA ISOURCE = 10mA, VS = 5V ISOURCE = 10mA, VS = 3V l l l l ISC Short-Circuit Current VS = 5V VS = 3V IS Supply Current GBW Gain Bandwidth Product (Note 5) f = 100kHz 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C l l 6.0 5.0 4.5 10 MHz MHz MHz SR Slew Rate (Note 5) AV = –1 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C l l 1.3 1.1 1.0 2.25 V/μs V/μs V/μs Minimum Supply Voltage VS – 0.14 VS – 0.05 VS – 0.30 VS – 0.2 VS – 0.39 VS – 0.3 VS – 0.59 VS – 0.3 25 15 V V V V 45 25 1.1 l mA mA 1.5 2.0 mA mA tr Output Rise Time 10% to 90%, 0.1V Step, RL = 10k 55 ns tf Output Fall Time 10% to 90%, 0.1V Step, RL = 10k 55 ns tS Settling Time VS = 5V, ΔVOUT = 2V to 0.1%, AV = –1 THD Distortion VS = 3V, VOUT = 1.8VP-P, AV = 1, RL = 10k, f = 1kHz FPBW Full-Power Bandwidth (Note 6) VOUT = 2VP-P 1.6 μs 0.001 % 360 kHz The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±5V, VCM = 0V, VOUT = 0V, pulse power tested unless otherwise specified. (Note 3) SYMBOL PARAMETER VOS Input Offset Voltage CONDITIONS 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C Input Bias Current l l l Input Offset Voltage Drift (Note 4) IB MIN VCM = V– VCM = V+ Input Bias Current Drift l l –300 TYP MAX 1 1.5 2.5 3.0 mV mV mV 5 20 μV/°C –150 50 100 nA nA l 0.1 l l 10 10 UNITS nA/°C Input Offset Current VCM = V– VCM = V+ Input Noise Voltage 0.1Hz to 10Hz 1 μVP-P en Input Noise Voltage Density f = 10kHz 20 nV/√Hz in Input Noise Current Density f = 10kHz f = 10kHz, VCM = 4.7V 0.23 0.15 pA/√Hz pA/√Hz IOS 25 25 nA nA 1797fb 3 LT1797 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.VS = ±5V, VCM = 0V, VOUT = 0V, pulse power tested unless otherwise specified. (Note 3) SYMBOL PARAMETER CONDITIONS MIN TYP RIN Input Resistance Differential Common Mode, VCM = –5V to 3.7V 200 330 100 kΩ MΩ CIN Input Capacitance 4 pF Input Voltage Range l –5 l l 78 66 96 76 l 400 300 1000 MAX 5 UNITS V CMRR Common Mode Rejection Ratio VCM = –5V to 3.7V VCM = –5V to 5V AVOL Large-Signal Voltage Gain VO = ±4V, RL = 10k VOL Output Voltage Swing LOW No Load, Input Overdrive = 30mV ISINK = 5mA ISINK = 10mA l l l VOH Output Voltage Swing HIGH No Load, Input Overdrive = 30mV ISOURCE = 5mA ISOURCE = 10mA l l l ISC Short-Circuit Current (Note 2) Short to GND PSRR Power Supply Rejection Ratio VS = ±1.35V to ±6V IS Supply Current GBW Gain Bandwidth Product f = 100kHz 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C l l 6.5 5.5 5.0 11 MHz MHz MHz SR Slew Rate AV = –1, RL = ∞, VO = ±4V, Measured at VO = ±2V 0°C ≤ TA ≤ 70°C –40°C ≤ TA ≤ 85°C l l 1.50 1.25 1.10 2.50 V/μs V/μs V/μs l –4.99 –4.92 –4.85 4.84 4.70 4.61 4.95 4.80 4.70 30 50 80 V/mV V/mV –4.97 –4.87 –4.79 V V V V V V mA 90 1.40 l dB dB dB 2.25 3.00 mA mA tr Output Rise Time 10% to 90%, 0.1V Step, RL = 10k 55 ns tf Output Fall Time 10% to 90%, 0.1V Step, RL = 10k 55 ns tS Settling Time ΔVOUT = 4V to 0.1%, AV = 1 2.6 μs FPBW Full-Power Bandwidth (Note 6) VOUT = 8VP-P 100 kHz Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: A heat sink may be required to keep the junction temperature below absolute maximum. Note 3: The LT1797C is guaranteed to meet 0°C to 70°C specifications and is designed, characterized and expected to meet the extended temperature limits, but is not tested at –40°C and 85°C. The LT1797I is guaranteed to meet specified performance from –40°C to 85°C. Note 4: This parameter is not 100% tested. Note 5: VS = 3V limit guaranteed by correlation to 5V tests. Note 6: Full-power bandwidth is calculated from the slew rate: FPBW = SR/2πVP 1797fb 4 LT1797 TYPICAL PERFORMANCE CHARACTERISTICS 1.2 TA = 25°C 1.0 TA = –55°C 0.8 0.6 0.4 0.2 100 200 50 INPUT BIAS CURRENT (nA) 1.4 300 100 0 TA = 125°C TA = 25°C –100 TA = –55°C –200 1 0 Output Saturation Voltage vs Load Current (Output High) OUTPUT SATURATION VOLTAGE (V) OUTPUT SATURATION VOLTAGE (V) 1 TA = 25°C TA = 125°C TA = –55°C 1μ Output Saturation Voltage vs Input Overdrive VS = ±2.5V VOD = 30mV 0.1 TA = 125°C 0.01 TA = –55°C TA = 25°C 10μ 100μ 1m SOURCING LOAD CURRENT (A) 10m 10μ 100μ 1m SINKING LOAD CURRENT (A) 1μ Output Short-Circuit Current vs Temperature 10m 100 INPUT NOISE VOLTAGE DENSITY (nV/√Hz) NOISE VOLTAGE (1μV/DIV) SOURCING CURRENT SINKING CURRENT 35 30 25 20 –50 –25 OUTPUT HIGH OUTPUT LOW 10 20 30 40 50 60 70 80 90 100 INPUT OVERDRIVE (mV) 0 Input Noise Voltage Density vs Frequency VS = ±5V 40 VS = ±2.5V IOUT = 0 1797 G06 0.1Hz to 10Hz Noise Voltage VS = ±2.5V 45 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0 1797 G05 1797 G04 OUTPUT CURRENT (mA) 1797 G03 0.001 0.01 50 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 COMMON MODE VOLTAGE (V) Output Saturation Voltage vs Load Current (Output Low) VS = ±2.5V VOD = 30mV 0.1 –100 1797 G02 1797 G01 1 –50 –200 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 TOTAL SUPPLY VOLTAGE (V) 2 3 4 5 6 7 8 9 10 11 12 TOTAL SUPPLY VOLTAGE (V) TA = –55°C TA = 25°C TA = 125°C –150 –300 0 VS = 5V, 0V 0 OUTPUT SATURATION VOLTAGE (mV) SUPPLY CURRENT (mA) TA = 125°C INPUT OFFSET VOLTAGE CHANGE (μV) 1.8 1.6 Input Bias Current vs Common Mode Voltage Minimum Supply Voltage Supply Current vs Supply Voltage VS = ±2.5V 80 60 40 20 0 50 25 75 0 TEMPERATURE (°C) 100 125 1797 G07 0 1 2 3 4 5 6 TIME (SEC) 7 8 9 10 1797 G08 10 100 1k 10k FREQUENCY (Hz) 100k 1797 G09 1797fb 5 LT1797 TYPICAL PERFORMANCE CHARACTERISTICS Gain and Phase Shift vs Frequency 70 VS = ±2.5V 1.0 50 GAIN (dB) 0.6 100 1k 10k FREQUENCY (Hz) 20 GAIN –20 0 –40 –10 –60 –20 –80 –30 10k 100k 0 100k GAIN BANDWIDTH PRODUCT (MHz) SLEW RATE (V/μs) FALLING 2.0 1.5 50 45 PHASE MARGIN 40 35 30 13 12 GAIN BANDWIDTH PRODUCT 11 10 100 125 8 NEGATIVE SUPPLY POSITIVE SUPPLY 40 30 20 10 0 –10 1 2 3 4 5 6 7 8 9 10 11 12 TOTAL SUPPLY VOLTAGE (V) 10k 100k 1M FREQUENCY (Hz) 10M 1797 G16 40 PHASE MARGIN 30 20 10 14 13 GAIN BANDWIDTH PRODUCT 12 11 10k RF = RG = (Ω) 1k 110 Output Impedance vs Frequency 100 VS = ±2.5V 100 100k 1797 G15 90 80 70 60 50 40 30 VS = ±2.5V GAIN = 100 10 1 GAIN = 10 0.1 20 10 1k 50 OUTPUT IMPEDANCE (Ω) 60 125 60 1797 G14 COMMON MODE REJECTION RATIO (dB) POWER SUPPLY REJECTION RATIO (dB) 70 100 VS = ±5V CMRR vs Frequency VS = ±2.5V 75 50 25 TEMPERATURE (°C) 0 10 0 PSRR vs Frequency 50 8.0 –50 –25 55 1797 G13 80 8.5 Gain Bandwidth Product and Phase Margin vs RF and RG 9 90 9.0 PHASE MARGIN (DEG) 2.5 50 25 0 75 TEMPERATURE (°C) VS = ±2.5V 9.5 1797 G12 PHASE MARGIN (DEG) RISING –25 10.0 60 f = 100kHz RF = RG = 1k VS = ±2.5V 3.0 VS = ±5V 10.5 Gain Bandwidth Product and Phase Margin vs Supply Voltage Slew Rate vs Temperature 1.0 –50 11.0 1797 G11 1797 G10 3.5 f = 100kHz 11.5 –100 100M 1M 10M FREQUENCY (Hz) GAIN BANDWIDTH PRODUCT (MHz) 0 10 40 10 0.4 0.2 60 30 20 12.0 80 PHASE 40 0.8 100 VS = ±2.5V 60 PHASE (DEG) INPUT NOISE CURRENT DENSITY (pA/√Hz) 1.2 Gain Bandwidth Product vs Temperature GAIN BANDWIDTH PRODUCT (MHz) Input Noise Current Density vs Frequency 1k 10k 100k 1M FREQUENCY (Hz) 10M 1797 G17 0.01 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1797 G18 1797fb 6 LT1797 TYPICAL PERFORMANCE CHARACTERISTICS Settling Time to 0.1% vs Output Step CHANGE IN INPUT OFFSET VOLTAGE (50μV/DIV) Open-Loop Gain 4 VS = ±5V 50 VS = ±5V AV = –1 AV = 1 40 RL = 10k RL = 2k OVERSHOOT (%) OUTPUT STEP (V) 2 RL = 50k 1 0 –1 –2 AV = 1 –3 AV = –1 Undistorted Output Swing vs Frequency 1 VS = ±5V 10 0.1 THD + NOISE (%) 9 8 7 6 5 4 VS = ±1.5V 3 15 AV = 5 AV = 10 0 10 100 1000 CAPACITIVE LOAD (pF) Total Harmonic Distortion + Noise vs Load Resistance 10 RL = 10k VS = 3V, 0V VOUT = 1.8VP-P VCM = 1V AV = 1 0.001 VS = 3V TOTAL AV = 1 f = 1kHz 1 AV = –1 0.01 VS = 3V, 0V VIN = 1.8VP-P VCM = 1.5V 0.1 0.01 VS = 3V, 0V VIN = 1.8VP-P VCM = 1V 1 1k 10k 100k FREQUENCY (Hz) 1M 0.0001 10 100 1k 10k FREQUENCY (Hz) 1797 G22 Total Harmonic Distortion + Noise vs Output Voltage Amplitude 10 10000 1797 G21 2 0 100 AV = 2 AV = 1 20 Total Harmonic Distortion + Noise vs Frequency AV = 1 11 25 1797 G20 1797 G19 12 30 5 –4 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 SETTLING TIME (μs) 5 35 10 THD + NOISE (%) 4 VS = ±2.5V 45 3 –5 –4 –3 –2 –1 0 1 2 3 OUTPUT VOLTAGE (V) OUTPUT SWING (VP-P) Capacitive Load Handling Overshoot vs Capacitive Load 100k 0.001 0.1 1 10 LOAD RESISTANCE TO GROUND (kΩ) 1797 G23 Large-Signal Response 100 1797 G24 Small-Signal Response f = 1kHz VCM = HALF SUPPLY RL = 10k THD + NOISE (%) 1 AV = –1 VS = 3V, 0V AV = 1 VS = ±1.5V 0.1 0.01 AV = 1 VS = 3V, 0V 0.001 0 1797 G26 AV = –1 VS = ±1.5V 2 1 OUTPUT VOLTAGE (VP-P) VS = ±2.5V AV = 1 3 1797 G27 VS = ±2.5V AV = 1 RL = 10k 1797 G25 1797fb 7 LT1797 APPLICATIONS INFORMATION Supply Voltage The positive supply pin of the LT1797 should be bypassed with a small capacitor (about 0.1μF) within an inch of the pin. When driving heavy loads an additional 4.7μF electrolytic capacitor should be used. When using split supplies the same is true for the negative supply pin. Inputs The LT1797 is fully functional for an input signal range from the negative supply to the positive supply. Figure 1 shows a simplified schematic of the amplifier. The input stage consists of two differential amplifiers, a PNP stage Q3/Q4 and an NPN stage Q1/Q2 that are active over different ranges of input common mode voltage. The PNP differential pair is active for input common mode voltages VCM between the negative supply to approximately 1.3V below the positive supply. As VCM moves closer toward the positive supply, the transistor QB1 will steer the tail current I1 to the current mirror Q5/Q6, activating the NPN differential pair and the PNP pair becomes inactive for the rest of the input common mode range up to the positive supply. The input offset voltage and the input bias current are dependent on which input stage is active. The input offset voltage is trimmed on a single 5V supply with the common mode at 1/2 supply and is typically 1mV with the PNP stage active. The input offset of the NPN stage is untrimmed and is typically 1.5mV. The input bias current polarity depends on the input common mode voltage. When the PNP differential pair is active, the input bias currents flow out of the input pins. They flow in the opposite direction when the NPN input stage is active. The offset error due to the input bias currents can be minimized by equalizing the noninverting and inverting source impedance. The input stage of the LT1797 incorporates phase reversal protection to prevent false outputs from occurring when the inputs are driven up to 5V beyond the rails. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced beyond the supplies or when a large differential signal is applied. Output The output is configured with a pair of complementary common emitter stages Q19/Q20, which enable the output to swing from rail-to-rail. The output voltage swing of the LT1797 is affected by input overdrive as shown in the Typical Performance Characteristics. When monitoring input voltages within 50mV of V+ or within 8mV of V–, some gain should be taken to keep the output from clipping. The output of the LT1797 can deliver large load currents; the short-circuit current limit is typically 50mA at ±5V. Take care to keep the junction temperature of the IC below the absolute maximum rating of 150°C. The output of the amplifier has reverse biased diodes to each supply. If the output is forced beyond either supply, unlimited current will flow through these diodes. The LT1797 can drive capacitive loads up to 200pF on a single 5V supply in a unity gain configuration. When there is a need to drive larger capacitive loads, a resistor of a couple hundred ohms should be connected between the output and the capacitive load. The feedback should still be taken from the output so that the resistor isolates the capacitive load to ensure stability. The low input bias current of the LT1797 makes it possible to use high value feedback resistors to set the gain. However, care must be taken to insure that the pole formed by the feedback resistors and the total capacitance at the inverting input does not degrade stability. 1797fb 8 LT1797 APPLICATIONS INFORMATION Distortion There are two main contributors to distortion in op amps: output crossover distortion as the output transitions from sourcing to sinking current and distortion caused by nonlinear common mode rejection. If the op amp is operating in the inverting mode, there is no common mode induced distortion. If the op amp is operating in the PNP input stage (input is not within 1.3V of V+), the CMRR is very good, typically 96dB. When the LT1797 switches between input stages there is significant nonlinearity in the CMRR. Lower load resistance increases the output crossover distortion, but has no effect on the input stage transition distortion. For lowest distortion the LT1797 should be operated single supply, with the output always sourcing current and with the input voltage swing between ground and (V+ – 1.3V). See the Typical Performance Characteristic curves. R1 Q17 Q18 I1 1/2 SUPPLY R2 Q15 Q16 Q19 QB1 BIAS C2 I7 Q13 Q14 R5 –IN Q1 Q2 Q9 Q10 D1 D2 I2 R6 I3 R7 +IN +1 R8 +1 CM OUT Q3 Q4 I4 I5 Q7 Q8 Q11 Q12 C1 Q5 Q6 Q20 R3 R4 I6 1797 F01 Figure 1. Simplified Schematic 1797fb 9 LT1797 TYPICAL APPLICATIONS Single Supply Hi-Gain 80kHz Photodiode Amplifier 3V R2 1k R3 10k C1 0.1μF + PHOTODIODE SFH213FA *CP = SUM OF PHOTODIODE CAPACITANCE, PARASITIC LAYOUT CAPACITANCE AND LT1797 INPUT CAPACITANCE 10pF. 3V R1 100k CP* TRANSIMPEDANCE GAIN: AZ = 10MΩ. R6 330Ω R6, C3 LIMIT THE NOISE BANDWIDTH TO 500kHz. LT1797 – C3 1000pF OUTPUT NOISE 1.8mVRMS. R1, CP AND LT1797 GBW SET UPPER LIMIT ON BANDWIDTH. R4, C2 SET LOWER 1.6kHz LIMIT ON GAIN OF 101. R5 R4 100k 1k C2 0.1μF 1797 TA02 1797fb 10 LT1797 TYPICAL APPLICATIONS Ultralow Noise, ±5V Supply, Rail-to-Rail Output Amplifier 5V IN 5V + + LT1028 – –5V R5 1k R2 4.99k LT1797 –5V C1 2200pF R4 10Ω OUT – R1 10k TOTAL INPUT VOLTAGE NOISE (INCLUDING 10Ω RESISTOR) BANDWIDTH 0.94nV/√Hz 40kHz AV = 500 R3 4.99k 1797 TA03 1797fb 11 LT1797 PACKAGE DESCRIPTION S5 Package 5-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1635) 0.62 MAX 0.95 REF 2.90 BSC (NOTE 4) 1.22 REF 1.4 MIN 3.85 MAX 2.62 REF 2.80 BSC 1.50 – 1.75 (NOTE 4) PIN ONE RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.30 – 0.45 TYP 5 PLCS (NOTE 3) 0.95 BSC 0.80 – 0.90 0.20 BSC 0.01 – 0.10 1.00 MAX DATUM ‘A’ 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) 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. JEDEC PACKAGE REFERENCE IS MO-193 1.90 BSC S5 TSOT-23 0302 REV B 1797fb 12 LT1797 REVISION HISTORY (Revision history begins at Rev B) REV DATE DESCRIPTION PAGE NUMBER B 6/10 Updated the last Feature. 1 Updated the package description in the Pin Configuration section. 2 Updated VOH in the Electrical Characteristics section. 3 Replaced the package drawing in the Package Description section. 12 1797fb 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. 13 LT1797 TYPICAL APPLICATION 1MHz Photodiode Transimpedance Amplifier Response of Photodiode Amplifier 3pF 100k V+ PHOTODIODE SFH213FA SIEMENS/INFINEON 100mV/DIV – LT1797 + VS = ±1.5V TO ±5V V– 1797 TA04 1797 TA04b 2μs/DIV Rise Time vs Supply Voltage (600mV Output Step) Supply Voltage 10% to 90% Rise Time ±1.5V 830ns ±2.5V 800ns ±5V 700ns RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1630/LT1631 Dual/Quad 30MHz, 10V/μs Rail-to-Rail Input and Output Op Amps High DC Accuracy, 525μV VOS(MAX), 70mA Output Current, Max Supply Current 4.4mA per Amp LT1638/LT1639 Dual/Quad 1.2MHz, 0.4V/μs, Over-The-Top™ Micropower Rail-to-Rail Input and Output Op Amps 170μA Supply Current, Single Supply Input Range –0.4V to 44V, Rail-to-Rail Input and Output LT1783 Micropower Over-The-Top SOT-23 Rail-to-Rail Input and Output Op Amp SOT-23 Package, Micropower 220μA per Amplifier, Rail-to-Rail Input and Output, 1.2MHz Gain Bandwidth LT1880 SOT-23 Rail-to-Rail Output, Picoamp Input Current Precision Op Amp 150μV Maximum Offset Voltage, 900pA Maximum Bias Current, 1.1MHz Gain Bandwidth, –40°C to 85°C Temperature Range 1797fb 14 Linear Technology Corporation LT 0610 REV B • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2000