LT6375 ±270V Common Mode Voltage Difference Amplifier FEATURES DESCRIPTION ±270V Common Mode Voltage Range nn 97dB Minimum CMRR (LT6375A) nn 0.0035% (35ppm) Maximum Gain Error (LT6375A) nn 1ppm/°C Maximum Gain Error Drift nn 2ppm Maximum Gain Nonlinearity nn Wide Supply Voltage Range: 3.3V to 50V nn Rail-to-Rail Output nn 350µA Supply Current nn Selectable Internal Resistor Divider Ratio nn 300µV Maximum Offset Voltage (LT6375A) nn 575kHz –3dB Bandwidth (Resistor Divider = 7) nn 375kHz –3dB Bandwidth (Resistor Divider = 20) nn –40°C to 125°C Specified Temperature Range nn Low Power Shutdown: 20μA (DFN Package Only) nn Space-Saving MSOP and DFN Packages The LT®6375 is a unity-gain difference amplifier which combines excellent DC precision, a very high input common mode range and a wide supply voltage range. It includes a precision op amp and a highly-matched thin film resistor network. It features excellent CMRR, extremely low gain error and extremely low gain drift. nn APPLICATIONS High Side or Low Side Current Sensing Bidirectional Wide Common Mode Range Current Sensing nn High Voltage to Low Voltage Level Translation nn Precision Difference Amplifier nn Industrial Data-Acquisition Front-Ends nn Replacement for Isolation Circuits nn nn Comparing the LT6375 to existing difference amplifiers with high common mode voltage range, the selectable resistor divider ratios of the LT6375 offer superior system performance by allowing the user to achieve maximum SNR, precision and speed for a specific input common mode voltage range. The op amp at the core of the LT6375 has Over-The-Top® protected inputs which allow for robust operation in environments with unpredictable voltage conditions. See the Applications Information section for more details. The LT6375 is specified over the –40°C to 125°C temperature range and is available in space-saving MSOP16 and DFN14 packages. L, LT, LTC, LTM, Linear Technology, Over-The-Top and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION Precision Wide Voltage Range, Bidirectional Current Monitor Typical Distribution of CMRR 15V –IN RSENSE 10Ω RC 10Ω +IN –REFB –REFC 19k 38k 23.75k 190k 180 160 190k – 190k 200 V+ OUT VOUT = ±10mV/mA + REF LOAD 19k 38k +REFA +REFB 23.75k +REFC 1248 UNITS FROM 4 RUNS VS = ±15V VIN = ±270V DIV = 25 140 120 100 80 60 40 20 190k SHDN NUMBER OF UNITS VSOURCE+ = –270V TO 270V –REFA V– –15V 6375 TA01a 0 –40 –30 –20 –10 0 10 20 CMRR (µV/V = ppm) 30 40 6375 TA01b 6375fa For more information www.linear.com/LT6375 1 LT6375 ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltages (V+ to V–)...............................................................60V +IN, –IN, (Note 2) Each Input..........................................................±270V Differential.........................................................±540V +REFA, –REFA, +REFB, –REFB, +REFC, –REFC, REF, SHDN (Note 2)................. (V+ + 0.3V) to (V– –0.3V) Output Current (Continuous) (Note 6).....................50mA Output Short-Circuit Duration (Note 3) Thermally Limited Temperature Range (Notes 4, 5) LT6375I................................................–40°C to 85°C LT6375H............................................. –40°C to 125°C Storage Temperature Range................... –65°C to 150°C MSOP Lead Temperature (Soldering, 10 sec)......... 300°C PIN CONFIGURATION TOP VIEW +IN +REFA TOP VIEW 14 –IN 1 3 – 12 –REFA +REFA 3 11 –REFB 5 6 7 8 +REFB 4 +REFC 5 10 –REFC REF 6 9 V+ SHDN 7 8 OUT 15 V +IN 1 +REFB +REFC REF V– 16 –IN 14 –REFA –REFB –REFC V+ OUT 12 11 10 9 MS PACKAGE VARIATION: MS16 (12) 16-LEAD PLASTIC MSOP TJMAX = 150°C, θJA = 130°C/W DF PACKAGE 14(12)-LEAD (4mm × 4mm) PLASTIC DFN TJMAX = 150°C, θJA = 43°C/W, θJC = 4°C/W EXPOSED PAD (PIN 15) IS V–, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT6375IDF#PBF LT6375IDF#TRPBF 6375 14-Lead (4mm × 4mm) Plastic DFN –40°C to 85°C LT6375HDF#PBF LT6375HDF#TRPBF 6375 14-Lead (4mm × 4mm) Plastic DFN –40°C to 125°C LT6375AHDF#PBF LT6375AHDF#TRPBF 6375 14-Lead (4mm × 4mm) Plastic DFN –40°C to 125°C LT6375IMS#PBF LT6375IMS#TRPBF 6375 16-Lead Plastic MSOP –40°C to 85°C LT6375HMS#PBF LT6375HMS#TRPBF 6375 16-Lead Plastic MSOP –40°C to 125°C LT6375AHMS#PBF LT6375AHMS#TRPBF 6375 16-Lead Plastic MSOP –40°C to 125°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. 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/. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix. 6375fa 2 For more information www.linear.com/LT6375 LT6375 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C < TA < 85°C for I-grade parts, –40°C < TA < 125°C for H-grade parts, otherwise specifications are at TA = 25°C, V+ = 15V, V– = –15V, VCM = VOUT = VREF = 0V. VCMOP is the common mode voltage of the internal op amp. For Resistor Divider Ratio = 7, ±REFA = ± REFC = OPEN, ±REFB = 0V. For Resistor Divider Ratio = 20, ±REFA = ±REFC = 0V, ±REFB = OPEN. For Resistor Divider Ratio = 25, ±REFA = ±REFB = ±REFC = 0V. LT6375A SYMBOL PARAMETER CONDITIONS G Gain VOUT = ±10V ∆G Gain Error VOUT = ±10V MIN Gain Drift vs Temperature (Note 6) VOUT = ±10V GNL Gain Nonlinearity VOUT = ±10V Output Offset Voltage V– < VCMOP < V+ –1.75V Resistor Divider Ratio = 7 Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 Resistor Divider Ratio = 25 VCM Input Voltage Range (Note 7) PSRR Power Supply Rejection Ratio VS = ±1.65V to ±25V, VCM = VOUT = Mid-Supply Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 % % ±1 ±2 ±3 ±1 ±2 ±3 ppm ppm 100 300 750 700 2000 900 2500 120 450 1500 1200 4000 1500 5000 3 8 9 23 4 10 12 30 µV/°C µV/°C 93 84 83 320 111 100 99 380 129 116 115 440 93 84 83 320 111 100 99 380 129 116 115 440 kΩ kΩ kΩ kΩ 96 94 96 94 96 94 97 94 106 89 83 89 83 89 83 90 83 100 104 89 83 89 83 89 83 90 83 100 l 94 92 94 92 94 92 95 92 l –270 l l l 101 93 91 l 250 l 300 l l l l l DF14 Package Resistor Divider Ratio = 7, VCM = ±28V Resistor Divider Ratio = 7, VCM = ±28V Resistor Divider Ratio = 20, VCM = ±28V Resistor Divider Ratio = 20, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±270V Resistor Divider Ratio = 25, VCM = ±270V ±0.001 ±0.006 ±0.0075 ppm/°C Common Mode Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 Differential V/V ±1 RIN MS16 Package Resistor Divider Ratio = 7, VCM = ±28V Resistor Divider Ratio = 7, VCM = ±28V Resistor Divider Ratio = 20, VCM = ±28V Resistor Divider Ratio = 20, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±28V Resistor Divider Ratio = 25, VCM = ±270V Resistor Divider Ratio = 25, VCM = ±270V 1 UNITS ±0.2 l l Common Mode Rejection Ratio MAX ±1 V– < VCMOP < V+ –1.75V Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 CMRR TYP ±0.2 l ∆VOS/∆T Output Offset Voltage Drift (Note 6) Input Impedance (Note 8) MIN ±0.0007 ±0.0035 ±0.005 l VOS LT6375 MAX 1 l ∆G/∆T TYP l l l l l l l 106 106 107 104 104 105 270 115 104 101 300 400 98 90 88 dB dB dB dB dB dB dB dB 100 100 100 dB dB dB dB dB dB dB dB 100 100 100 –270 270 110 100 100 µV µV µV µV µV µV V dB dB dB 6375fa For more information www.linear.com/LT6375 3 LT6375 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C < TA < 85°C for I-grade parts, –40°C < TA < 125°C for H-grade parts, otherwise specifications are at TA = 25°C, V+ = 15V, V– = –15V, VCM = VOUT = VREF = 0V. VCMOP is the common mode voltage of the internal op amp. For Resistor Divider Ratio = 7, ±REFA = ± REFC = OPEN, ±REFB = 0V. For Resistor Divider Ratio = 20, ±REFA = ±REFC = 0V, ±REFB = OPEN. For Resistor Divider Ratio = 25, ±REFA = ±REFB = ±REFC = 0V. LT6375A SYMBOL PARAMETER eno Output Referred Noise Voltage Density Output Referred Noise Voltage CONDITIONS MIN TYP LT6375 MAX MIN TYP MAX UNITS f = 1kHz Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 250 508 599 250 508 599 nV/√Hz nV/√Hz nV/√Hz f = 0.1Hz to 10Hz Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 10 20 25 10 20 25 µVP-P µVP-P µVP-P VOL Output Voltage Swing Low (Referred to V–) No Load ISINK = 5mA l l 5 280 50 500 5 280 50 500 mV mV VOH Output Voltage Swing High (Referred to V+) No Load ISOURCE = 5mA l l 5 400 20 750 5 400 20 750 mV mV ISC Short-Circuit Output Current 50Ω to V+ 50Ω to V– l l 10 10 SR Slew Rate ∆VOUT = ±5V l 1.6 BW Small Signal –3dB Bandwidth Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 575 375 310 tS Settling Time Resistor Divider Ratio = 7 0.01%, ∆VOUT = 10V 0.1%, ∆VOUT = 10V 0.01%, ∆VCM = 10V, ∆VDIFF = 0V 41 14 100 41 14 100 µs µs µs Resistor Divider Ratio = 20 0.01%, ∆VOUT = 10V 0.1%, ∆VOUT = 10V 0.01%, ∆VCM = 10V, ∆VDIFF = 0V 31 11 100 31 11 100 µs µs µs Resistor Divider Ratio = 25 0.01%, ∆VOUT = 10V 0.1%, ∆VOUT = 10V 0.01%, ∆VCM = 10V, ∆VDIFF = 0V 26 8 20 26 8 20 µs µs µs VS Supply Voltage l tON Turn-On Time VIL SHDN Input Logic Low (Referred to V+) l VIH SHDN Input Logic High (Referred to V+) l ISHDN SHDN Pin Current IS Supply Current 28 30 10 10 2.4 1.6 3 3.3 50 50 mA mA 2.4 V/µs 575 375 310 kHz kHz kHz 3 3.3 16 50 50 16 –2.5 –1.2 l Active, VSHDN ≥ V+ –1.2V Active, VSHDN ≥ V+ –1.2V Shutdown, VSHDN ≤ V+ –2.5V Shutdown, VSHDN ≤ V+ –2.5V 28 30 µs –2.5 –1.2 V V –10 –15 –10 –15 µA 350 400 600 25 70 350 400 600 25 70 µA µA µA µA l 20 l V V 20 6375fa 4 For more information www.linear.com/LT6375 LT6375 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C < TA < 85°C for I-grade parts, –40°C < TA < 125°C for H-grade parts, otherwise specifications are at TA = 25°C, V+ = 5V, V– = 0V, VCM = VOUT = VREF = Mid-Supply. VCMOP is the common mode voltage of the internal op amp. For Resistor Divider Ratio = 7, ±REFA = ±REFC = OPEN, ±REFB = Mid-Supply. For Resistor Divider Ratio = 20, ±REFA = ±REFC = Mid-Supply, ±REFB = OPEN. For Resistor Divider Ratio = 25, ±REFA = ±REFB = ±REFC = Mid-Supply. LT6375A SYMBOL PARAMETER CONDITIONS MIN G Gain VOUT = 1V to 4V ∆G Gain Error VOUT = 1V to 4V Gain Drift vs Temperature (Note 6) VOUT = 1V to 4V GNL Gain Nonlinearity VOUT = 1V to 4V VOS Output Offset Voltage MIN 1 ±0.2 l TYP MAX 1 ±1 ±0.2 UNITS V/V ±0.001 ±0.006 ±0.0075 ±1 < V+ –1.75V 0 < VCMOP Resistor Divider Ratio = 7 Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 Resistor Divider Ratio = 25 MAX ±0.0007 ±0.0035 ±0.005 l ∆G/∆T TYP LT6375 ±1 ±1 % % ppm/°C ppm 120 3 8 9 23 4 10 12 30 µV/°C µV/°C 129 116 115 440 93 84 83 320 111 100 99 380 129 116 115 440 kΩ kΩ kΩ kΩ 250 l 300 l 300 400 500 1500 1200 4000 1500 5000 µV µV µV µV µV µV 300 750 700 2000 900 2500 100 l ∆VOS/∆T Output Offset Voltage Drift (Note 6) 0 < VCMOP < V+ –1.75V Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 l l RIN Common Mode Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 Differential l l l l 93 84 83 320 111 100 99 380 94 92 105 85 83 95 l dB dB 94 92 105 85 83 95 l dB dB 94 92 105 85 83 95 l dB dB 92 90 103 85 83 95 l dB dB 92 90 103 85 83 95 l dB dB 92 90 103 85 83 95 l dB dB PSRR Power Supply Rejection Ratio VS = ±1.65V to ±25V, VCM = VOUT = Mid-Supply l Resistor Divider Ratio = 7 l Resistor Divider Ratio = 20 l Resistor Divider Ratio = 25 101 93 91 115 104 101 98 90 88 110 100 100 dB dB dB eno Output Referred Noise Voltage Density 250 508 599 nV/√Hz nV/√Hz nV/√Hz CMRR Input Impedance (Note 8) Common Mode Rejection Ratio MS16 Package Resistor Divider Ratio = 7 VCM = –15V to +7.75V VCM = –15V to +7.75V Resistor Divider Ratio = 20 VCM = –25.5V to +17.5V VCM = –25.5V to +17.5V Resistor Divider Ratio = 25 VCM = –25.5V to +21.25V VCM = –25.5V to +21.25V DF14 Package Resistor Divider Ratio = 7 VCM = –15V to +7.75V VCM = –15V to +7.75V Resistor Divider Ratio = 20 VCM = –25.5V to +17.5V VCM = –25.5V to +17.5V Resistor Divider Ratio = 25 VCM = –25.5V to +21.25V VCM = –25.5V to +21.25V f = 1kHz Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 250 508 599 6375fa For more information www.linear.com/LT6375 5 LT6375 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C < TA < 85°C for I-grade parts, –40°C < TA < 125°C for H-grade parts, otherwise specifications are at TA = 25°C, V+ = 5V, V– = 0V, VCM = VOUT = VREF = Mid-Supply. VCMOP is the common mode voltage of the internal op amp. For Resistor Divider Ratio = 7, ±REFA = ±REFC = OPEN, ±REFB = Mid-Supply. For Resistor Divider Ratio = 20, ±REFA = ±REFC = Mid-Supply, ±REFB = OPEN. For Resistor Divider Ratio = 25, ±REFA = ±REFB = ±REFC = Mid-Supply. LT6375A SYMBOL PARAMETER CONDITIONS MIN TYP LT6375 MAX MIN TYP MAX UNITS Output Referred Noise Voltage f = 0.1Hz to 10Hz Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 VOL Output Voltage Swing Low (Referred to V–) No Load ISINK = 5mA l l 5 280 50 500 5 280 50 500 mV mV VOH Output Voltage Swing High (Referred to V+) No Load ISOURCE = 5mA l l 5 400 20 750 5 400 20 750 mV mV ISC Short-Circuit Output Current 50Ω to V+ 50Ω to V– l l 10 10 27 25 10 10 27 25 mA mA SR Slew Rate ∆VOUT = 3V l 1.3 2 1.3 2 V/µs BW Small Signal –3dB Bandwidth Resistor Divider Ratio = 7 Resistor Divider Ratio = 20 Resistor Divider Ratio = 25 565 380 325 565 380 325 kHz kHz kHz tS Settling Time Resistor Divider Ratio = 7 0.01%, ∆VOUT = 2V 0.1%, ∆VOUT = 2V 0.01%, ∆VCM = 2V, ∆VDIFF = 0V 18 10 64 18 10 64 µs µs µs Resistor Divider Ratio = 20 0.01%, ∆VOUT = 2V 0.1%, ∆VOUT = 2V 0.01%, ∆VCM = 2V, ∆VDIFF = 0V 24 7 48 24 7 48 µs µs µs Resistor Divider Ratio = 25 0.01%, ∆VOUT = 2V 0.1%, ∆VOUT = 2V 0.01%, ∆VCM = 2V, ∆VDIFF = 0V 27 9 20 27 9 20 µs µs µs 10 20 25 VS Supply Voltage l tON Turn-On Time VIL SHDN Input Logic Low (Referred to V+) l VIH SHDN Input Logic High (Referred to V+) l ISHDN SHDN Pin Current IS Supply Current 3 3.3 10 20 25 50 50 3 3.3 22 50 50 22 –2.5 –1.2 l Active, VSHDN ≥ V+ –1.2V Active, VSHDN ≥ V+ –1.2V Shutdown, VSHDN ≤ V+ –2.5V Shutdown, VSHDN ≤ V+ –2.5V V V µs –2.5 –1.2 V V –10 –15 –10 –15 µA 330 370 525 20 40 330 370 525 20 40 µA µA µA µA l 15 l µVP-P µVP-P µVP-P 15 6375fa 6 For more information www.linear.com/LT6375 LT6375 ELECTRICAL CHARACTERISTICS 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: See Common Mode Voltage Range in the Applications Information section of this data sheet for other considerations when taking +IN/–IN pins to ±270V. All other pins should not be taken more than 0.3V beyond the supply rails. Note 3: A heat sink may be required to keep the junction temperature below absolute maximum. This depends on the power supply, input voltages and the output current. Note 4: The LT6375I is guaranteed functional over the operating temperature range of –40°C to 85°C. The LT6375H is guaranteed functional over the operating temperature range of –40°C to 125°C. Note 5: The LT6375I is guaranteed to meet specified performance from –40°C to 85°C. The LT6375H is guaranteed to meet specified performance from –40°C to 125°C. Note 6: This parameter is not 100% tested. Note 7: Input voltage range is guaranteed by the CMRR test at VS = ±15V and all REF pins at ground (Resistor Divider Ratio = 25). For the other voltages, this parameter is guaranteed by design and through correlation with the ±15V test. See Common Mode Voltage Range in the Applications Information section to determine the valid input voltage range under various operating conditions. Note 8: Input impedance is tested by a combination of direct measurement and correlation to the CMRR and gain error tests. TYPICAL PERFORMANCE CHARACTERISTICS Typical Distribution of CMRR 180 VS = ±15V VIN = ±270V DIV = 25 90 80 140 NUMBER OF UNITS 120 100 80 60 655 UNITS FROM 2 RUNS MS16(12) VS = ±15V VIN = ±270V DIV = 25 90 80 70 60 50 40 30 50 40 30 20 20 10 10 30 40 6375 G01 350 1248 UNITS FROM 4 RUNS BOTH PACKAGES 0 –40 –30 –20 –10 0 10 20 CMRR (µV/V = ppm) 40 6375 G02 Typical Distribution of Gain Error 400 30 VS = ±15V VOUT = ±10V 175 300 655 UNITS FROM 2 RUNS MS16(12) NUMBER OF UNITS 200 150 VS = ±15V VOUT = ±10V 175 125 VS = ±15V VOUT = ±10V 100 75 125 100 75 50 50 50 25 25 6375 G04 593 UNITS FROM 2 RUNS DF14(12) 150 100 0 –50 –40 –30 –20 –10 0 10 20 30 40 50 GAIN ERROR (ppm) 40 Typical Distribution of Gain Error 200 150 250 30 6375 G03 Typical Distribution of Gain Error 200 VS = ±15V VIN = ±270V DIV = 25 60 20 0 –40 –30 –20 –10 0 10 20 CMRR (µV/V = ppm) 593 UNITS FROM 2 RUNS DF14(12) 70 40 0 –40 –30 –20 –10 0 10 20 CMRR (µV/V = ppm) NUMBER OF UNITS Typical Distribution of CMRR 100 NUMBER OF UNITS NUMBER OF UNITS 160 1248 UNITS FROM 4 RUNS BOTH PACKAGES Typical Distribution of CMRR 100 NUMBER OF UNITS 200 TA = 25°C, VS = ±15V, unless otherwise noted. 0 –50 –40 –30 –20 –10 0 10 20 30 40 50 GAIN ERROR (ppm) 6375 G05 0 –50 –40 –30 –20 –10 0 10 20 30 40 50 GAIN ERROR (ppm) 6375 G06 6375fa For more information www.linear.com/LT6375 7 LT6375 TYPICAL PERFORMANCE CHARACTERISTICS Typical Distribution of Gain Nonlinearity COMMON MODE REJECTION RATIO (dB) NUMBER OF UNITS 120 1332 UNITS VS = ±15V FROM 4 RUNS VOUT = ±10V BOTH PACKAGES 250 200 150 100 50 0 0 Common Mode Voltage Range vs Power Supply Voltage CMRR vs Frequency DIV = 7 MS16(12) 100 80 60 40 20 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 GAIN NONLINEARITY (ppm) 10 100 1k 10k 100k FREQUENCY (Hz) 1M VS = ±12V VS = ±10V 50 0 –50 –100 –150 –200 –250 VS = ±15V VS = ±12V VS = ±10V ERROR (ppm) VS = ±5V, RL = 10kΩ 6375 G13 VS = ±12V VS = ±10V –20 –16 –12 –8 –4 0 4 8 12 16 20 OUTPUT VOLTAGE (V) 6375 G12 Gain Nonlinearity 100 VS = ±15V RL = 2kΩ 80 60 60 40 40 20 0 –20 0 –20 –40 –60 –60 –100 –15 VS = ±15V RL = 10kΩ 20 –40 –80 –80 5 VS = ±15V Gain Nonlinearity 80 30 VS = ±18V 6375 G11 100 VS = ±2.5V, RL = 1kΩ 5 10 15 20 25 POWER SUPPLY VOLTAGE (±V) Typical Gain Error for RL = 2kΩ (Curves Offset for Clarity) VS = ±18V Typical Gain Error for Low Supply Voltages (Curves Offset for Clarity) VS = ±5V, RL = 1kΩ 0 LT6375 G09 –20 –16 –12 –8 –4 0 4 8 12 16 20 OUTPUT VOLTAGE (V) 6375 G10 VS = ±5V, RL = 2kΩ DIV = 7 DIV = 10 DIV = 12 DIV = 15 DIV = 17 DIV = 20 DIV = 25 OTT 100 OUTPUT ERROR (2mV/DIV) VS = ±15V –20 –16 –12 –8 –4 0 4 8 12 16 20 OUTPUT VOLTAGE (V) OUTPUT ERROR (2mV/DIV) 150 –300 10M ERROR (ppm) VS = ±18V 4 200 Typical Gain Error for RL = 5kΩ (Curves Offset for Clarity) OUTPUT ERROR (2mV/DIV) OUTPUT ERROR (2mV/DIV) Typical Gain Error for RL = 10kΩ (Curves Offset for Clarity) 3 250 6375 G08 6375 G07 –5 –4 –3 –2 –1 0 1 2 OUTPUT VOLTAGE (V) 300 COMMON MODE OPERATING RANGE (V) 300 TA = 25°C, VS = ±15V, unless otherwise noted. –10 –5 0 5 OUTPUT VOLTAGE (V) 10 15 6375 G14 –100 –15 –10 –5 0 5 OUTPUT VOLTAGE (V) 10 15 6375 G15 6375fa 8 For more information www.linear.com/LT6375 LT6375 TYPICAL PERFORMANCE CHARACTERISTICS Gain Nonlinearity Gain Nonlinearity 10 100 VS = ±15V RL = 1MΩ 40 4 ERROR (ppm) 6 20 0 –20 –40 GAIN ERROR (ppm) 8 60 Gain Error vs Temperature 2 0 –80 –100 –15 –10 –5 0 5 OUTPUT VOLTAGE (V) 10 15 0 0 –6 –60 –6 –8 –80 –8 –10 –15 –10 –5 0 5 OUTPUT VOLTAGE (V) 10 –10 –100 –75 –50 –25 0 25 50 75 100 125 150 175 TEMPERATURE (°C) 15 6375 G18 6375 G17 Maximum Power Dissipation vs Temperature Gain vs Frequency 10 5 130°C 85°C 25°C –45°C –10 –15 5 10 15 20 25 OUTPUT CURRENT (mA) 20 10 DF14(12) θJA = 43°C/W 4 0 –10 3 GAIN (dB) MAXIMUM POWER DISSIPATION (W) 15 2 1 –10 –20 –30 –50 –60 –70 –80 0.001 0nF 0.5nF 1nF 1.5nF 2nF 3nF 5nF 0.01 0.1 1 FREQUENCY (MHz) –80 0.001 10 6375 G22 DIV = 7 DIV = 10 DIV = 12 DIV = 15 DIV = 17 DIV = 20 DIV = 25 0.01 0.1 1 FREQUENCY (MHz) 0.1Hz to 10Hz Noise 1100 50 1000 40 30 900 20 800 700 600 DIV = 20 500 0 –10 –30 DIV = 7 300 1 10 100 1k FREQUENCY (Hz) DIV = 7 10 –20 400 200 10 6375 G21 NOISE (µV) DIV = 20 0 –40 –70 Noise Density vs Frequency VOLTAGE NOISE DENSITY (nV/√Hz) 10 –40 LT6375 G20 Frequency Response vs Capacitive Load 20 –30 –60 MS16(12) θJA = 130°C/W 0 –60 –40 –20 0 20 40 60 80 100 120 140 160 AMBIENT TEMPERATURE (°C) 30 –20 –50 6375 G19 GAIN (dB) 2 5 0 4 20 –4 20 –5 6 –2 Output Voltage vs Load Current 0 8 –40 6375 G16 –20 VS = ±15V 80 VOUT = ±10V RL = 10kΩ 60 10 UNITS 40 –20 –2 –4 –60 10 100 GAIN ERROR (m%) ERROR (ppm) VS = ±15V 80 RL = 100kΩ OUTPUT VOLTAGE (V) TA = 25°C, VS = ±15V, unless otherwise noted. DIV = 20 –40 10k 100k 6375 G23 –50 TIME (10s/DIV) 6375 G24 6375fa For more information www.linear.com/LT6375 9 LT6375 TYPICAL PERFORMANCE CHARACTERISTICS Negative PSRR vs Frequency 120 120 110 110 DIV = 20 90 80 70 DIV = 7 DIV = 25 60 50 40 30 20 10 0 10 100 1k 10k FREQUENCY (Hz) 100 90 80 DIV = 7 70 DIV = 20 60 50 40 30 DIV = 25 20 0 5 4 10 2 100 1k 10k FREQUENCY (Hz) 0 –75 –50 –25 0 25 50 75 100 125 150 175 TEMPERATURE (°C) 100k 6375 G26 6375 G27 Small-Signal Step Response vs Capacitive Load Small-Signal Step Response Large-Signal Step Response 140 DIV = 7 CL = 560pF RL = 2kΩ DIV = 7 RL = 2kΩ 120 100 80 VOLTAGE (mV) VOLTAGE (25mV/DIV) DIV = 7 CL = 560pF RL = 2kΩ 0V RL = 10kΩ 3 1 10 100k VS = ±2.5V, Rising VS = ±15V, Rising VS = ±25V, Rising VS = ±2.5V, Falling VS = ±15V, Falling VS = ±25V, Falling 6 6375 G25 VOLTAGE (5V/DIV) Slew Rate vs Temperature 7 SLEW RATE (V/µs) 100 POWER SUPPLY REJECTION RATIO (dB) POWER SUPPLY REJECTION RATIO (dB) Positive PSRR vs Frequency TA = 25°C, VS = ±15V, unless otherwise noted. 0V 60 560pF 40 20 0 1000pF –20 –40 20pF –60 –80 –100 5 10 6375 G29 6375 G28 Large-Signal Step Response 140 35 40 DIV = 20 RL = 2kΩ 120 100 80 VOLTAGE (mV) VOLTAGE (25mV/DIV) 30 Small-Signal Step Response vs Capacitive Load DIV = 20 CL = 560pF RL = 2kΩ 0V 15 20 25 TIME (µs) 6375 G30 Small-Signal Step Response DIV = 20 CL = 560pF RL = 2kΩ VOLTAGE (5V/DIV) 0 TIME (4µs/DIV) TIME (4µs/DIV) 0V 60 560pF 40 20 1000pF 0 –20 20pF –40 –60 –80 –100 TIME (4µs/DIV) TIME (4µs/DIV) 6375 G31 6375 G32 0 5 10 15 20 25 TIME (µs) 30 35 40 6375 G33 6375fa 10 For more information www.linear.com/LT6375 LT6375 TYPICAL PERFORMANCE CHARACTERISTICS 3.5 1.0 14 0.5 8 2.0 1.5 6 ERROR VOLTAGE 1.0 4 –2 –1.0 –4 –1.5 –6 –2.0 –8 OUTPUT VOLTAGE –2.5 3000 2 –10 DIV = 20 10 UNITS 2250 0 ERROR VOLTAGE –0.5 4 OUTPUT VOLTAGE (V) 10 DIV = 7 0 12 OUTPUT VOLTAGE OUTPUT VOLTAGE (V) ERROR VOLTAGE (mV) 16 1500 OFFSET VOLTAGE (µV) DIV = 7 ERROR VOLTAGE (mV) 4.0 2.5 Output Offset Voltage vs Temperature Settling Time Settling Time 3.0 TA = 25°C, VS = ±15V, unless otherwise noted. 750 0 –750 0.5 2 0 0 –3.0 –12 –0.5 –2 –3.5 –14 –2250 –1.0 –4 –4.0 –16 –3000 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE (°C) TIME (10µs/DIV) TIME (10µs/DIV) 6375 G35 6375 G34 10 UNITS 600 600 500 500 450 400 350 300 QUIESCENT CURRENT (µA) SUPPLY CURRENT (µA) 400 300 200 100 250 0 145 200 –75 –50 –25 0 25 50 75 100 125 150 175 TEMPERATURE (°C) 150 155 160 165 TEMPERATURE (°C) Shutdown Quiescent Current vs Supply Voltage 150°C 125°C 85°C 200 TA = –55°C 100 PARAMETRIC SWEEP IN ~25°C INCREMENTS 550 VSHDN = 0V 150°C 125°C 85°C 500 30 20 10 0 450 25°C –40°C –55°C VS = ±15V 400 350 300 250 200 150 100 0 10 20 30 40 SUPPLY VOLTAGE (V) 50 LT6375 G40 0 20 30 40 SUPPLY VOLTAGE (V) 50 Minimum Supply Voltage 150 DIV = 7 100 50 TA = 125°C 0 –50 TA = 25°C –100 50 0 10 6375 G39 Quiescent Current vs SHDN Voltage QUIESCENT CURRENT (µA) 40 25°C –40°C –55°C 300 6375 G38 6375 G37 50 400 0 170 CHANGE IN OFFSET VOLTAGE (µV) QUIESCENT CURRENT (µA) Quiescent Current vs Supply Voltage TA = 150°C 500 QUIESCENT CURRENT (µA) 6375 G36 Thermal Shutdown Hysteresis Quiescent Current vs Temperature 550 –1500 TA = –45°C 0 5 10 SHDN VOLTAGE (V) 15 6375 G41 –150 0 1 2 3 4 TOTAL SUPPLY VOLTAGE (V) 5 6375 G42 6375fa For more information www.linear.com/LT6375 11 LT6375 TYPICAL PERFORMANCE CHARACTERISTICS Typical Distribution of Output Offset Voltage Typical Distribution of Output Offset Voltage 175 200 DIV = 7 1332 UNITS FROM 4 RUNS BOTH PACKAGES 175 125 100 75 175 125 100 75 125 100 75 50 50 25 25 25 0 –1200 –800 –400 0 400 OFFSET VOLTAGE (µV) 800 6375 G43 1352 UNITS FROM 4 RUNS BOTH PACKAGES Typical Distribution of PSRR 200 1352 UNITS FROM 4 RUNS 175 BOTH PACKAGES VS = ±1.65V TO ±25V DIV = 7 Typical Distribution of PSRR 200 VS = ±1.65V TO ±25V DIV = 20 1352 UNITS FROM 4 RUNS 175 BOTH PACKAGES 150 NUMBER OF UNITS 150 125 100 75 125 100 75 125 100 75 50 50 25 25 25 6 8 10 6375 G46 VS = ±1.65V TO ±25V DIV = 25 150 50 0 –10 –8 –6 –4 –2 0 2 4 PSRR (µV/V) 1500 6375 G45 NUMBER OF UNITS 175 0 –1500 –1000 –500 0 500 1000 OFFSET VOLTAGE (µV) 1200 6375 G44 Typical Distribution of PSRR 200 DIV = 25 1332 UNITS FROM 4 RUNS BOTH PACKAGES 150 50 0 –400 –300 –200 –100 0 100 200 300 400 OFFSET VOLTAGE (µV) NUMBER OF UNITS 200 DIV = 20 1332 UNITS FROM 4 RUNS BOTH PACKAGES 150 NUMBER OF UNITS NUMBER OF UNITS 150 Typical Distribution of Output Offset Voltage NUMBER OF UNITS 200 TA = 25°C, VS = ±15V, unless otherwise noted. 0 –25 –20 –15 –10 –5 0 5 10 15 20 25 PSRR (µV/V) 6375 G47 0 –30 –20 –10 0 10 PSRR (µV/V) 20 30 6375 G48 6375fa 12 For more information www.linear.com/LT6375 LT6375 PIN FUNCTIONS (DFN/MSOP) V+ (Pin 9/Pin 10):Positive Supply Pin. V– (Exposed Pad Pin 15/Pin 8):Negative Supply Pin. OUT (Pin 8/Pin 9):Output Pin. +IN (Pin 1/Pin 1):Noninverting Input Pin. Accepts input voltages from 270V to –270V. +REFA (Pin 3/Pin 3): Reference Pin A. Sets the input common mode range and the output noise and offset. +REFB (Pin 4/Pin 5): Reference Pin B. Sets the input common mode range and the output noise and offset. +REFC (Pin 5/Pin 6): Reference Pin C. Sets the input common mode range and the output noise and offset. –REFA (Pin 12/Pin 14): Reference Pin A. Sets the input common mode range and the output noise and offset. –REFB (Pin 11/Pin 12): Reference Pin B. Sets the input common mode range and the output noise and offset. –REFC (Pin 10/Pin 11): Reference Pin C. Sets the input common mode range and the output noise and offset. REF (Pin 6/Pin 7):Reference Input. Sets the output level when the difference between the inputs is zero. SHDN (Pin 7) DFN Only:Shutdown Pin. Amplifier is active when this pin is tied to V+ or left floating. Pulling the pin >2.5V below V+ causes the amplifier to enter a low power state. –IN (Pin 14/Pin 16): Inverting Input Pin. Accepts input voltages from 270V to –270V. 6375fa For more information www.linear.com/LT6375 13 LT6375 BLOCK DIAGRAM –REFA 19k –REFB 38k V+ –REFC 23.75k 190k –IN 190k +IN 190k – OUT + REF 190k V+ 19k +REFA 38k +REFB 23.75k +REFC 10µA SHDN V– 6375 BD APPLICATIONS INFORMATION TRANSFER FUNCTION The LT6375 is a unity-gain difference amplifier with the transfer function: VOUT = (V+IN – V–IN) + VREF The voltage on the REF pin sets the output voltage when the differential input voltage (VDIFF = V+IN – V–IN) is zero. This reference is used to shift the output voltage to the desired input level of the next stage of the signal chain. BENEFITS OF SELECTABLE RESISTOR DIVIDER RATIOS The LT6375 offers smaller package size, better gain accuracy and better noise performance than existing high common mode voltage range difference amplifiers. Additionally, the LT6375 allows the user to maximize system performance by selecting the resistor divider ratio (DIV) appropriate to their input common mode voltage range. A higher resistor divider ratio (DIV) enables higher common mode voltage range at the input pins, but also increases output noise, output offset/drift and decreases the –3dB bandwidth. Therefore, a trade-off exists between input range and DC, AC, and drift performance of the part. It is recommended that the user choose the lowest resistor divider ratio that achieves the required input common mode voltage range in their application to maximize the system SNR, precision and speed. Table 1 shows the noise, offset/drift, and –3dB bandwidth of the LT6375 for all different reference pins configurations. COMMON MODE VOLTAGE RANGE The wide common mode voltage range of the LT6375 is enabled by both a resistor divider at the input of the op amp and by an internal op amp that can withstand high input voltages. The internal resistor network of the LT6375 divides down the input common mode voltage. The resulting voltage at the op amp inputs determines the op amp’s operating region. In the configuration shown in Figure 1, a resistor divider is created at both op amp inputs by the 190k input resistor and the resistance from each input to ground, which is ~31.66k. The resistance to ground is formed by the 38k (REFB resistors) in parallel with the 190k (feedback/REF resistor). The result is a divide by 7 of the input voltage. As shown in Tables 1 to 5, different connections to reference pins (i.e. pins +REFA, –REFA, +REFB, –REFB, 6375fa 14 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION Table 1. LT6375 Performance at Different Resistor Divider Ratios RESISTOR DIVIDER OPTIONS RESISTOR OUTPUT +REFA AND +REFB AND +REFC AND DIVIDER DIFFERENTIAL NOISE AT MAXIMUM OFFSET –REFC REF RATIO (DIV) –REFA –REFB GAIN 1kHz (nV/√Hz) (µV) 19k 38k 23.75k 190k OPEN GND OPEN REF 7 1 OPEN OPEN GND REF 10 1 –3dB MAXIMUM OFFSET BANDWIDTH DRIFT (µV/°C) (kHz) LT6375A LT6375 LT6375A LT6375 250 300 450 9 12 575 307 380 600 12 16 530 GND OPEN OPEN REF 12 1 346 450 720 14 19 485 OPEN GND GND REF 15 1 410 540 900 16 22 445 GND GND OPEN REF 17 1 445 600 1000 19 25 405 GND OPEN GND REF 20 1 508 700 1200 23 30 375 GND GND GND REF 25 1 599 900 1500 28 37 310 +REFC, –REFC) result in different resistor divider ratios (DIV) and different attenuation of the LT6375’s input common mode voltage. The internal op amp of LT6375 has two operating regions: a) If the common mode voltage at the inputs of the internal op amp (VCMOP) is between V– and V+ –1.75V, the op amp operates in its normal region; b) If VCMOP is between V+ –1.75V and V– +76V, the op amp continues to operate, but in its Over-The-Top region with degraded performance (see Over-The-Top operation section of this data sheet for more detail). VS+ V–IN V+IN –REFA –REFB –REFC 19k 38k 23.75k –IN 190k +IN 190k V+ 190k – OUT + REF 19k 38k +REFA +REFB 190k 23.75k +REFC SHDN V– 6375 F01 VS+ VS– Figure 1. Basic Connections for Dual-Supply Operation (Resistor Divider Ratio = 7) VOUT Table 2 lists the valid input common mode voltage range for an LT6375 with different configurations of the reference pins when used with dual power supplies. Using the voltage ranges in this table ensures that the internal op amp is operating in its normal (and best) region. The figure entitled Common Mode Voltage Range vs Power Supply Voltage, in the Typical Performance Characteristics section of this data sheet, illustrates the information in Table 2 graphically. Table 3 lists the valid input common mode voltage range for an LT6375 that results in the internal op amp operating in its Over-The-Top region. The reference pins can be connected to ground (as in Tables 2 and 3) or to any reference voltage. In order to achieve the specified gain accuracy and CMRR performance of the LT6375, this reference must have a very low impedance. The valid input common mode range changes depending on the voltages chosen for reference pins. One positive and one negative reference should always be connected to a low impedance voltage to ensure the stability of the amplifier. Table 4 lists the valid input common mode voltage range for an LT6375 when the part is used with a single power supply, and REF and the other reference pins are connected to mid-supply. If, as shown in Table 5, the REF pin remains connected to mid-supply, while the other reference pins are connected to ground, the result is a higher positive input range at the expense of a more restricted negative input range. 6375fa For more information www.linear.com/LT6375 15 LT6375 APPLICATIONS INFORMATION Table 2. Common Mode Voltage Operating Range with Dual Power Supplies (Normal Region) Table 5. Common Mode Voltage Operating Range with a Single Power Supply, References to GND (Normal Region) INPUT RANGE (REF = GND) INPUT RANGE (REF = VS/2) +REFA +REFB +REFC VS = ±2.5V AND AND AND –REFA –REFB –REFC DIV HIGH LOW OPEN GND OPEN 7 5.25 OPEN OPEN VS = ±15V VS = ±25V HIGH LOW HIGH LOW –17.5 92.75 –105 162.75 –175 132.5 –150 232.5 –250 +REFA +REFB +REFC VS = 5V AND AND AND –REFA –REFB –REFC DIV HIGH LOW OPEN GND OPEN 7 OPEN OPEN 20.25 VS = 30V VS = 50V HIGH LOW HIGH LOW –2.5 182.75 –15 270 –25 GND 10 7.5 –25 GND 10 30 –2.5 267.5 –15 270 –25 GND OPEN OPEN 12 9 –30 –180 270 –270 GND OPEN OPEN 12 36.5 –2.5 270 –15 270 –25 OPEN GND GND 15 11.25 –37.5 198.75 –225 270 –270 OPEN GND GND 15 46.25 –2.5 270 –15 270 –25 GND 159 GND OPEN 17 12.75 –42.5 225.25 –255 GND OPEN GND 20 GND GND 25 18.75 –62.5 GND 15 –50 270 –270 GND GND OPEN 17 52.75 –2.5 270 –15 270 –25 265 –270 270 –270 GND OPEN GND 20 62.5 –2.5 270 –15 270 –25 270 –270 270 –270 GND GND 25 78.75 –2.5 270 –15 270 –25 Table 3. Common Mode Voltage Operating Range with Dual Power Supplies (Over-The-Top Region) INPUT RANGE (REF = GND) +REFA +REFB +REFC VS = ±2.5V AND AND AND –REFA –REFB –REFC DIV HIGH LOW VS = ±15V VS = ±25V HIGH LOW HIGH LOW OPEN GND OPEN 7 270 –17.5 270 –105 270 –175 OPEN OPEN GND 10 270 –25 270 –150 270 –250 GND OPEN OPEN 12 270 –30 270 –180 270 –270 OPEN GND GND 15 270 –37.5 270 –225 270 –270 GND GND OPEN 17 270 –42.5 270 –255 270 –270 GND OPEN GND 20 270 –50 270 –270 270 –270 GND GND 25 270 –62.5 270 –270 270 –270 GND Table 4. Common Mode Voltage Operating Range with a Single Power Supply, References to Mid-Supply (Normal Region) INPUT RANGE (REF = VS/2) +REFA +REFB +REFC VS = 5V AND AND AND –REFA –REFB –REFC DIV HIGH LOW VS = 30V HIGH LOW HIGH LOW OPEN 7 7.75 –15 107.75 –90 187.75 –150 OPEN OPEN VS/2 10 10 –22.5 147.5 –135 257.5 –225 11.5 VS/2 OPEN OPEN 12 –165 270 –270 OPEN VS/2 VS/2 15 13.75 –35 213.75 –210 270 –270 VS/2 VS/2 OPEN 17 15.25 –40 240.25 –240 270 –270 VS/2 OPEN VS/2 20 VS/2 VS/2 25 21.25 VS/2 17.5 174 The LT6375 will not operate correctly if the common mode voltage at its input pins goes below the range specified in above tables, but the part will not be damaged as long as the lowest common mode voltage at the inputs of the internal op amp (VCMOP) remains between V– –25V and V–. Also, the voltage at LT6375 input pins should never be higher than 270V or lower than –270V under any circumstances. SHUTDOWN The LT6375 in the DFN14 package has a shutdown pin (SHDN). Under normal operation this pin should be tied to V+ or allowed to float. Tying this pin to 2.5V below V+ will cause the part to enter a low power state. The supply current is reduced to less than 25µA and the op amp output becomes high impedance. VS = 50V OPEN VS/2 –27.5 GND –47.5 270 –270 270 –270 –60 270 –270 270 –270 SUPPLY VOLTAGE The positive supply pin of the LT6375 should be bypassed with a small capacitor (typically 0.1µF) as close to the supply pin as possible. When driving heavy loads an additional 4.7µF electrolytic capacitor should be added. When using split supplies, the same is true for the V– supply pin. 6375fa 16 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION ACCURATE CURRENT MEASUREMENTS The LT6375 can be used in high side, low side and bidirectional wide common mode range current sensing. Figure 2 shows the LT6375 sensing current by measuring the voltage across RSENSE. The added sense resistors create a CMRR error and a gain error. For RSENSE greater than 2Ω the source resistance mismatch degrades the CMRR. Adding a resistor equal in value to RSENSE in series with the +IN terminal (RC) eliminates this mismatch. Using an RSENSE greater than 10Ω will cause the gain error to exceed the 0.006% specification of LT6375. This is due to the loading effects of the LT6375. VOUT = ILOAD • RSENSE • 190k/(190k + RSENSE) Increasing RSENSE and RC slightly to RSENSE' removes the gain error. RSENSE' = RSENSE • 190k/(190k – RSENSE). NOISE AND FILTERING The noise performance of the LT6375 can be optimized both by appropriate choice of its internal attenuation setting and by the addition of a filter to the amplifier output (Figure 3). For applications that do not require the full bandwidth of the LT6375, the addition of an output filter will lower system noise. Table 6 shows the output noise for different internal resistor divider ratios and output filter bandwidths. VS+ = 15V –REFA –REFB –REFC 19k 38k 23.75k V+ 190k + = 270V VSOURCE RSENSE RC –IN 190k +IN 190k – OUT VOUT ≅ RSENSE • ILOAD + ILOAD REF 19k 38k +REFA +REFB 190k 23.75k +REFC SHDN VS+ VREF V– VS– = –15V LOAD VS+ = 15V ILOAD RSENSE RC –REFA –REFB –REFC 19k 38k 23.75k –IN 190k +IN 190k V+ 190k – OUT VOUT ≅ RSENSE • ILOAD + REF VSOURCE– = –270V 19k 38k +REFA +REFB 190k 23.75k +REFC SHDN VREF V– 6375 F02 VS+ VS– = –15V Figure 2. Wide Voltage Range Current Sensing 6375fa For more information www.linear.com/LT6375 17 LT6375 APPLICATIONS INFORMATION VS+ V–IN V+IN –REFA –REFB –REFC 19k 38k 23.75k V+ 190k – 190k –IN – 190k +IN C2 OUT R1 + 38k +REFA +REFB 190k 23.75k +REFC VOUT + C1 REF 19k LT6015 R2 VREF V– SHDN 6375 F03 VS+ VS– Figure 3. Output Filtering with 2-Pole Butterworth Filter Table 6. Output Noise (VP-P) for 2-Pole Butterworth Filter for Different Internal Resistor Divider Ratios Table 7. Component Values for Different 2-Pole Butterworth Filter Bandwidths Corner Frequency Corner Frequency 7 10 12 15 17 20 25 No Filter 1705µV 1831µV 1901µV 2008µV 2073µV 2177µV 2330µV 100kHz 537µV 662µV 740µV 853µV 925µV 1030µV 1197µV 10kHz 169µV 210µV 236µV 274µV 298µV 334µV 393µV 1kHz 54µV 67µV 75µV 87µV 95µV 107µV 126µV 100Hz 18µV 22µV 25µV 29µV 32µV 36µV R1 R2 C1 C2 100kHz 11kΩ 11.3kΩ 100pF 200pF 10kHz 11kΩ 11.3kΩ 1nF 2nF 1kHz 11kΩ 11.3kΩ 10nF 20nF 100Hz 11kΩ 11.3kΩ 0.1µF 0.2µF 43µV 15V –REFA –REFB –REFC 19k 38k 23.75k VSOURCE+ = 195V RSENSE 10Ω RC, 10Ω –IN 190k +IN 190k V+ 190k – OUT + 1A LOAD VOUT REF 19k 38k +REFA +REFB 23.75k +REFC 190k V– SHDN 6375 F04 –15V Figure 4. Current Measurement Application 6375fa 18 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION ERROR BUDGET ANALYSIS Figure 4 shows the LT6375 in a current measurement application. The error budget for this application is shown in Table 8. The resistor divider ratio is set to 15 to divide the 195V input common mode voltage down to 13V at the op amp inputs. The 1A current and 10Ω sense resistor produce an output full-scale voltage of 10V. Table 8 shows the error sources in parts per million (ppm) of the full-scale voltage across the temperature range of 25°C to 85°C. Different sources of error contribute to the maximum accuracy that can be achieved in an application. Gain error, offset voltage and common mode rejection error combine to set the initial error. Additionally, the gain error and offset voltage drift across the temperature range. The excellent gain accuracy, low offset voltage, high CMRR, low offset voltage drift and low gain error drift of the LT6375 all combine to enable extremely accurate measurements. Over-The-Top OPERATION When the input common mode voltage of the internal op amp (VCMOP) in the LT6375 is biased near or above the V+ supply, the op amp is operating in the Over-The-Top region. The op amp continues to operate with an input common mode voltage of up to 76V above V– (regardless of the positive power supply voltage V+), but its performance is degraded. The op amp’s input bias currents change from under ±2nA to 14µA. The op amp’s input offset current rises to ±50nA which adds ±9.5mV to the output offset voltage. In addition, when operating in the Over-The-Top region, the differential input impedance decreases from 1MΩ in normal operation to approximately 3.7kΩ in Over-The-Top operation. This resistance appears across the summing nodes of the internal op amp and boosts noise and offset while decreasing speed. Noise and offset will increase by between 66% and 83% depending on the resistor divider ratio setting. The bandwidth will be reduced by 40% to 45%. For more detail on Over-The-Top operation, consult the LT6015 data sheet. OUTPUT The output of the LT6375 can typically swing to within 5mV of either rail with no load and is capable of sourcing and sinking approximately 25mA. The LT6375 is internally compensated to drive at least 1nF of capacitance under any output loading conditions. For larger capacitive loads, a 0.22µF capacitor in series with a 150Ω resistor between the output and ground will compensate the amplifier to drive capacitive loads greater than 1nF. Additionally, the LT6375 has more gain and phase margin as the resistor divider ratio is increased. Table 8. Error Budget Analysis ERROR, ppm of FS ERROR SOURCE LT6375A LT6375 COMPETITOR 1 COMPETITOR 2 LT6375A LT6375 COMPETITOR 1 COMPETITOR 2 0.0035% FS 0.006% FS 0.02% FS 0.03% FS 35 60 200 300 Offset Voltage 540µV 900µV 1100µV 500µV 54 90 110 50 Common Mode 195V/96dB = 3090µV 195V/89dB = 6920µV 195V/90dB = 6166µV 195V/86dB = 9770µV 309 692 617 977 398 842 927 1327 60 60 600 600 Accuracy, TA = 25°C Initial Gain Error Total Accuracy Error Temperature Drift Gain 1ppm/°C ×60°C 1ppm/°C ×60°C Offset Voltage 16µV/°C ×60°C 22µV/°C ×60°C 10ppm/°C ×60°C 10ppm/°C ×60°C 15µV/°C ×60°C 10µV/°C ×60°C 96 132 90 60 Total Drift Error 156 192 690 660 Total Error 554 1034 1617 1987 6375fa For more information www.linear.com/LT6375 19 LT6375 APPLICATIONS INFORMATION DISTORTION The LT6375 features excellent distortion performance when the internal op amp is operating within the supply rails. Operating the LT6375 with input common mode voltages that go from normal to Over-The-Top operation will significantly degrade the LT6375’s linearity as the op amp must transition between two different input stages. POWER DISSIPATION CONSIDERATIONS Because of the ability of the LT6375 to operate on power supplies up to ±25V, to withstand very high input voltages and to drive heavy loads, there is a need to ensure the die junction temperature does not exceed 150°C. The LT6375 is housed in DF14 (θJA = 43°C/W, θJC = 4°C/W) and MS16 (θJA = 130°C/W) packages. In general, the die junction temperature (TJ) can be estimated from the ambient temperature (TA), and the device power dissipation (PD): TJ = TA + PD • θJA Power is dissipated by the amplifier’s quiescent current, by the output current driving a resistive load and by the input current driving the LT6375’s internal resistor network. PD = ((VS+ – VS–) • IS) + POD + PRESD The power dissipated in the internal resistors (PRESD) depends on the input voltage, the resistor divider ratio (DIV), the output voltage and the voltage on REF and the other reference pins. The following equations and Figure 5 show different components of PRESD corresponding to different groups of LT6375’s internal resistors (assuming that LT6375 is used with a dual supply configuration with REF and all reference pins at ground). PRESDA = (V+IN)2/(190k + 190k/(DIV – 1)) PRESDB = (V–IN – V+IN/DIV)2/(190k) PRESDC = (V+IN/DIV)2/(190k/(DIV – 2)) PRESDD = (V+IN/DIV – VOUT)2/(190k) PRESD = PRESDA + PRESDB + PRESDC + PRESDD PRESD simplifies to: PRESD = 2(V+IN2((DIV – 1)/DIV – VOUT/V+IN) + VOUT2)/190k In general, PRESD increases with higher input voltage, higher resistor divider ratio (DIV), and lower output, REF and reference pin voltages. Example: An LT6375 in a DFN package mounted on a PC board has a thermal resistance of 43°C/W. Operating on ±25V supplies and driving a 2.5kΩ load to 12.5V with V+IN = 270V and DIV = 25, the total power dissipation is given by: For a given supply voltage, the worst-case output power dissipation POD(MAX) occurs with the output voltage at half of either supply voltage. POD(MAX) is given by: PD = (50 • 0.6mA) + 12.52/2.5k + 2702/197.92k + (257.5 – 270/25)2/190k + (270/25)2/8.26k + (270/25 – 12.5)2/190k = 0.795W POD(MAX) = (VS/2)2/RLOAD VS+ = 25V –REFA –REFB –REFC 19k 38k 23.75k PRESDC V+ PRESDD 190k PRESDB V–IN = 270V – VOUT = 257.5V V+IN = 270V –IN +IN 190k 190k – PRESDA OUT VOUT = 12.5V + REF 19k 38k +REFA +REFB 23.75k +REFC 190k SHDN V– VS_ = –25V 6375 F05 Figure 5. Power Dissipation Example 6375fa 20 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION Assuming a thermal resistance of 43°C/W, the die temperature will experience a 34°C rise above ambient. This implies that the maximum ambient temperature the LT6375 should operate under the above conditions is: TA =150°C – 34°C = 116°C Keep in mind that the DFN package has an exposed pad which can be used to lower the θJA of the package. The more PCB metal connected to the exposed pad, the lower the thermal resistance. The MSOP package has no exposed pad and a higher thermal resistance (θJA = 130°C/W). It should not be used in applications which have a high ambient temperature, require driving a heavy load, or require an extreme input voltage. THERMAL SHUTDOWN For safety, the LT6375 will enter shutdown mode when the die temperature rises to approximately 163°C. This thermal shutdown has approximately 9°C of hysteresis requiring the die temperature to cool 9°C before enabling the amplifier again. USE AT OTHER PRECISION DC GAINS The array of resistors within the LT6375 provides numerous configurable connections that provide precision gains other than the unity differential gain options described previously. Note that only the +IN and –IN pins can operate outside of the supply window. Since most of these alternate configurations involve driving the REFx pins, as well as the +IN and –IN pins, the input signals must be less than the supply voltages. Fully differential gains are available as shown in Table 9, and may be output-shifted with a REF offset signal. These configurations allow the LT6375 to be used as a versatile precision gain block with essentially no external components besides the supply decoupling. In most cases, only a single positive supply will be required. In Table 9, connections are identified as NC (no connect), INPUT (refers to both inputs driven, +signal to +pins,–signal to –pins), CROSS (refers to inputs cross-coupled, +signal to –pins, –signal to +pins), OUT (refers to the output fed back to –pins), or REF (refers to connecting the REF pin to +pins). The same configurations provide inverting gains by grounding any pins intended for the +signal source. The differential input resistance is also tabulated as well as the amplification factor of the internal gain section involved (noise-gain, which helps to estimate the error-budget of the configuration). Single-ended noninverting gains are also available as shown in Table 10, including many that operate as buffers (loaded only by the op amp input bias). A rich option set exists by using the REF pin as an additional variable. Two attenuation options exist that can accept signals outside the power supply range since they only drive the +IN pin. In Table 10, connections are identified as NC (no connect), INPUT (driven by the input), OUT (fed back from the output), or GROUND (grounded). Table 10 also includes tabulations of the internal resistor divider (DIV), noise gain (re-amplification), and the input loading presented by the circuit. USE AS PRECISION AC GAIN BLOCK In AC-coupled applications operating from a single power supply, it is useful to set the output voltage at mid-supply to maximize dynamic range. The LT6375 readily supports this with no additional biasing components by connecting specific pins to the V+ and V– potentials and AC-coupling the signal paths. Table 11 shows the available inverting gains and also tabulates the load resistances presented at the input. In Table 11, connections are identified as NC (no connect), AC IN (AC-coupled to the input) OUT (fed back from the output), tied to V+, tied to V–, or AC GND (ACgrounded). All pins that require an AC ground can share a single bypass capacitor. Likewise, all pins driven from the source signal may share a coupling capacitor as well. The output should also connect to the load circuitry using a coupling capacitor to block the mid-supply DC voltage. The LT6375 may also be used for single-supply noninverting AC gains by employing a combination of input attenuation and re-amplification. With numerous choices of attenuation and re-amplification, several hundred overall gain combinations are possible, ranging from 0.167 to 23. The combinations are more plentiful than the DC configurations because there is no constraint on matching internal source resistances to minimize offset. 6375fa For more information www.linear.com/LT6375 21 LT6375 APPLICATIONS INFORMATION The input attenuator section dedicates some pins to establishing a mid-supply bias point and with the remaining pins, provides several choices of input signal division factors as shown in Table 12. The high attenuations that only use +IN for the signal path can accept waveform peaks that significantly exceed the supply range. Table 12 also includes tabulations of the resulting AC load resistance presented to the signal source. Here again, all pins that require an AC-ground connection may share a single bypass capacitor, and all AC signal connections may share a coupling capacitor. Note that configurations with +IN to V+ will bias at 50% of supply, while the others shown will bias at 38% of supply. The single-supply AC-coupled noninverting circuit is completed by configuring the post-attenuator amplification factor. Table 13 shows the available re-amplification factors. Once again, all pins that require an AC-ground connection may share a single bypass capacitor, and the output should use a coupling capacitor to its load destination as well. Table 9. Configurations for Precision Differential Gains Other Than Unity LT6375 DIFFERENTIAL AND INVERTING PRECISION DC GAINS GAIN ±IN ±REFA ±REFB ±REFC REF DIFF RIN (k) NOISE GAIN 0.167 CROSS INPUT OUT/REF CROSS REF 20 4.2 0.333 NC INPUT OUT/REF CROSS REF 21 4.0 0.5 INPUT INPUT OUT/REF CROSS REF 20 4.2 1.5 OUT/REF NC CROSS INPUT REF 29 7.5 2 CROSS NC CROSS INPUT REF 27 15.0 2.5 OUT/REF INPUT CROSS NC REF 25 8.5 2.833 CROSS INPUT OUT/REF INPUT REF 20 4.2 3 NC INPUT OUT/REF INPUT REF 21 4.0 3.167 INPUT INPUT OUT/REF INPUT REF 20 4.2 3.5 OUT/REF INPUT INPUT CROSS REF 17 12.5 4 CROSS NC INPUT NC REF 63 7.0 5 NC NC INPUT NC REF 76 6.0 6 INPUT NC INPUT NC REF 63 7.0 7 CROSS NC NC INPUT REF 42 10.0 8 NC NC NC INPUT REF 48 9.0 9 INPUT NC NC INPUT REF 42 10.0 10 NC INPUT NC NC REF 38 11.0 11 INPUT INPUT NC NC REF 35 12.0 12 CROSS NC INPUT INPUT REF 27 15.0 13 NC NC INPUT INPUT REF 29 14.0 14 INPUT NC INPUT INPUT REF 27 15.0 15 NC INPUT INPUT NC REF 25 16.0 16 INPUT INPUT INPUT NC REF 24 17.0 17 CROSS INPUT NC INPUT REF 20 20.0 18 NC INPUT NC INPUT REF 21 19.0 19 INPUT INPUT NC INPUT REF 20 20.0 22 CROSS INPUT INPUT INPUT REF 16 25.0 23 NC INPUT INPUT INPUT REF 17 24.0 24 INPUT INPUT INPUT INPUT REF 16 25.0 6375fa 22 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION Table 10. Configurations for Precision Noninverting Gains LT6375 NONINVERTING PRECISION DC GAINS GAIN FEATURE +IN +REFA +REFB +REFC REF –IN –REFA –REFB –REFC NOISE GAIN DIV RIN (k) GROUND 4.167 25 198 0.167 Wide Input INPUT GROUND GROUND GROUND GROUND GROUND GROUND OUT 0.333 INPUT GROUND GROUND GROUND 0.5 Wide Input INPUT OUT GROUND 4.167 12.5 103 OUT NC NC GROUND 5 10 302 GROUND GROUND NC GROUND OUT GROUND 4 4.8 48 GROUND OUT NC NC GROUND 5 5 170 OUT GROUND 4.167 3.571 38 INPUT NC NC 0.833 NC GROUND INPUT 1 INPUT NC NC INPUT 1.167 INPUT GROUND INPUT GROUND INPUT 1.333 GROUND GROUND GROUND 1.5 NC GROUND GROUND GROUND GROUND GROUND GROUND GROUND GROUND INPUT NC NC GROUND OUT GROUND 4 3 36 INPUT INPUT NC GROUND OUT GROUND 4 2.667 34 1.667 NC INPUT GROUND GROUND GROUND NC GROUND OUT GROUND 4 2.400 33 1.833 INPUT INPUT GROUND GROUND NC NC GROUND OUT GROUND 4 2.182 32 2 INPUT NC 2.167 GROUND GROUND GROUND NC INPUT GROUND NC GROUND NC 7 3.500 37 INPUT INPUT NC NC GROUND OUT GROUND 4 1.846 32 2.333 INPUT GROUND INPUT INPUT NC NC GROUND OUT GROUND 4 1.714 33 2.5 NC GROUND INPUT NC NC OUT NC 7.5 3 57 2.667 INPUT INPUT INPUT GROUND NC NC GROUND OUT GROUND 4 1.500 36 2.833 INPUT INPUT INPUT GROUND INPUT GROUND GROUND OUT GROUND 4.167 1.471 35 GROUND GROUND 3 INPUT NC INPUT 3.167 INPUT INPUT GROUND INPUT NC 3.333 INPUT INPUT GROUND INPUT INPUT 3.5 INPUT NC INPUT GROUND 3.833 GROUND INPUT INPUT INPUT INPUT OUT NC 7.5 2.500 53 NC GROUND OUT GROUND 4 1.263 48 GROUND GROUND OUT GROUND 4.167 1.250 47 OUT INPUT INPUT NC NC INPUT GROUND OUT Buffer 7.5 Buffer 8 GROUND 4 1 Hi-Z GROUND 4.167 1 Hi-Z NC GROUND 5 1.111 302 NC NC INPUT 7 103 OUT INPUT INPUT 6.5 51 1.087 OUT INPUT INPUT Buffer 2.143 GROUND INPUT INPUT 6 7.5 4.167 GROUND GROUND INPUT Buffer Buffer GROUND GROUND GROUND Buffer 5 GROUND GROUND OUT 4 5.5 NC GROUND GROUND GROUND 4.167 4.5 GROUND GROUND NC NC INPUT NC NC NC OUT NC NC GROUND 5 1 Hi-Z INPUT INPUT NC NC GROUND OUT GROUND NC NC 6 1.091 226 INPUT NC INPUT NC NC NC NC GROUND NC 6 1 Hi-Z GROUND NC INPUT INPUT GROUND OUT NC GROUND GROUND 7.5 1.154 110 INPUT NC INPUT NC INPUT GROUND NC GROUND 7 1 Hi-Z GROUND GROUND NC INPUT INPUT NC NC OUT NC NC NC NC INPUT GROUND NC NC NC NC INPUT GROUND OUT NC 7.5 1 Hi-Z GROUND 9 1.125 321 NC 8.5 1 Hi-Z 8.5 Buffer NC 9 Buffer INPUT NC NC INPUT NC NC NC NC GROUND 9 1 Hi-Z INPUT INPUT NC INPUT GROUND OUT GROUND NC GROUND 10 1.053 200 9.5 GROUND GROUND NC 10 Buffer NC INPUT NC NC NC GROUND NC NC GROUND 10 1 Hi-Z 11 Buffer INPUT INPUT NC NC NC NC GROUND NC NC 11 1 Hi-Z GROUND INPUT INPUT INPUT GROUND OUT GROUND GROUND GROUND 12.5 1.087 103 11.5 6375fa For more information www.linear.com/LT6375 23 LT6375 APPLICATIONS INFORMATION Table 10. Configurations for Precision Noninverting Gains GAIN FEATURE +IN +REFA +REFB +REFC REF 12 Buffer INPUT INPUT NC NC INPUT 12.5 Buffer INPUT INPUT INPUT INPUT INPUT OUT NC NC INPUT INPUT GROUND NC NC Buffer INPUT NC INPUT INPUT NC NC NC NC 13 14 –IN GROUND GROUND 15 Buffer NC INPUT INPUT NC NC GROUND 16 Buffer INPUT INPUT INPUT NC NC NC 17 Buffer NC NC NC NC INPUT 19 Buffer INPUT INPUT 20 Buffer INPUT INPUT NC INPUT INPUT NC INPUT INPUT INPUT GROUND NC NC 18 23 –REFA –REFB –REFC NOISE GAIN DIV RIN (k) NC NC 12 1 Hi-Z 12.5 1 Hi-Z GROUND GROUND 14 1.077 205 GROUND GROUND 14 1 Hi-Z GROUND GROUND GROUND GROUND GROUND 15 1 Hi-Z GROUND GROUND NC 16 1 Hi-Z INPUT GROUND GROUND GROUND GROUND NC 17 1 Hi-Z NC INPUT GROUND NC GROUND NC GROUND 19 1.056 201 NC INPUT NC NC GROUND NC GROUND 19 1 Hi-Z GROUND GROUND NC GROUND 20 1 Hi-Z GROUND GROUND GROUND 24 1.043 198 GROUND GROUND GROUND 24 1 Hi-Z GROUND GROUND GROUND GROUND 25 1 Hi-Z 24 Buffer INPUT INPUT INPUT INPUT NC 25 Buffer INPUT INPUT INPUT INPUT INPUT Table 11. Configurations for Single-Supply AC-Coupled Inverting Gains LT6375 SINGLE-SUPPLY INVERTING AC GAINS GAIN –IN –REFA –REFB –REFC +IN +REFA AC GND AC GND +REFC REF AC RIN (k) AC GND AC GND V– 11 AC GND AC GND V– 10 38 +REFB –3 NC AC IN OUT AC IN V+ –3.167 AC IN AC IN OUT AC IN V+ AC GND AC GND AC GND V– AC GND AC GND AC GND V– 32 AC GND V– 24 21 –5 NC NC AC IN NC V+ –6 AC IN NC AC IN NC V+ AC IN V+ AC GND AC GND AC GND V– AC GND AC GND AC GND V– 19 AC GND V– 17 15 –8 NC NC NC AC GND AC GND –9 AC IN NC NC AC IN V+ –10 NC AC IN NC NC V+ NC V+ AC GND AC GND AC GND V– AC GND AC GND AC GND V– 14 13 –11 AC IN AC IN NC AC GND AC GND –13 NC NC AC IN AC IN V+ –14 AC IN NC AC IN AC IN V+ AC GND AC GND AC GND V– AC GND AC GND AC GND V– 12 AC GND V– 11 10 –15 NC AC IN AC IN NC V+ –16 AC IN AC IN AC IN NC V+ AC IN V+ AC GND AC GND AC GND V– AC GND AC GND AC GND V– 8 AC GND V– 8 –18 NC AC IN NC –19 AC IN AC IN NC AC IN V+ –23 NC AC IN AC IN AC IN V+ AC IN V+ –24 AC IN AC IN AC IN AC GND AC GND AC GND AC GND 6375fa 24 For more information www.linear.com/LT6375 LT6375 APPLICATIONS INFORMATION Table 12. Configurations for Single-Supply AC-Coupled Input Attenuations LT6375 SINGLE-SUPPLY AC ATTENUATOR CONFIGURATIONS DIV +IN +REFA +REFB +REFC REF AC RIN (k) 1.087 V+ AC IN AC IN AC IN V– 103 1.111 V+ AC IN V– 106 1.133 V+ AC IN AC IN NC V– 108 1.154 V+ NC AC IN AC IN V– 110 1.2 V+ NC V– 114 1.25 V+ NC NC AC IN V– 119 1.389 V+ AC IN AC GND AC IN V– 38 1.4 V+ NC AC IN NC V– 133 1.7 V+ AC IN AC GND NC V– 46 1.875 V+ AC IN V– 51 1.923 V+ AC GND AC IN AC IN V– 30 2.083 AC IN AC IN V+ V– AC IN 30 2.182 AC IN AC IN V+ V– NC 32 2.273 AC IN AC IN V+ V– AC GND 31 AC IN V+ V– NC 34 V– AC GND 33 AC GND V– 32 AC IN V– 35 54 2.3 NC AC IN AC IN NC NC NC AC GND 2.4 NC AC IN V+ 2.5 V+ AC IN AC GND 3.125 V+ 3.4 V+ AC GND AC IN NC V– 5 V+ AC GND AC IN AC GND V– 47 V– AC GND AC GND 7.5 AC IN NC V+ AC IN 110 12 AC IN AC GND V+ V– AC IN 103 NC V+ V– NC 205 V– 14 AC IN 15 AC IN NC V+ AC GND 204 24 AC IN AC GND V+ V– NC 198 25 AC IN AC GND V+ V– AC GND 198 6375fa For more information www.linear.com/LT6375 25 LT6375 APPLICATIONS INFORMATION Table 13. Configurations for Single-Supply AC-Coupled Re-Amplications LT6375 NONINVERTING AC RE-AMPLIFICATIONS GAIN –IN –REFA –REFB –REFC 4 NC AC GND OUT AC GND 4.167 AC GND AC GND OUT AC GND 5 OUT NC NC AC GND 6 NC NC AC GND NC 7 AC GND NC AC GND NC 7.5 OUT NC AC GND AC GND 8.5 OUT AC GND AC GND NC 9 NC NC NC AC GND 10 AC GND NC NC AC GND 11 NC AC GND NC NC 12 AC GND AC GND NC NC 12.5 OUT AC GND AC GND AC GND 14 NC NC AC GND AC GND 15 AC GND NC AC GND AC GND 16 NC AC GND AC GND NC 17 AC GND AC GND AC GND NC 19 NC AC GND NC AC GND 20 AC GND AC GND NC AC GND 24 NC AC GND AC GND AC GND 25 AC GND AC GND AC GND AC GND 6375fa 26 For more information www.linear.com/LT6375 LT6375 TYPICAL APPLICATIONS Telecom Supply Monitor VS = 12V VBAT = 48V –REFA –REFB –REFC 19k 38k 23.75k –IN 190k +IN 190k V+ 190k – OUT VOUT = + VBAT 6 REF 19k 38k +REFA +REFB 190k 23.75k +REFC V– SHDN 6375 TA02 27dB Audio Gain Stage VS = 3.3V TO 50V 2.2µF VIN –IN +IN –REFA –REFB –REFC 19k 38k 23.75k 190k V+ 190k – 190k 2.2µF OUT + VOUT REF 19k 38k +REFA +REFB 23.75k +REFC VOUT VIN = –24 190k SHDN V– 6375 TA03 2.2µF 6375fa For more information www.linear.com/LT6375 27 LT6375 TYPICAL APPLICATIONS ±5mA Howland Current Source V S+ VCTL = ±1V –REFA –REFB –REFC 19k 38k 23.75k –IN 190k +IN 190k V+ 190k – OUT + VOUT RS 32.4Ω IOUT = REF 19k 38k +REFA +REFB 23.75k +REFC 190k VCTL 6 • RS – VOUT 41.6k LOAD SHDN V– 6375 TA04 VS– Precision Reference Divider/Buffer VREF –REFA –REFB –REFC 19k 38k 23.75k –IN 190k +IN 190k V+ 190k – OUT + VOUT = VREF 2 REF 19k 38k +REFA +REFB 23.75k +REFC 190k SHDN V– 6375 TA05 6375fa 28 For more information www.linear.com/LT6375 LT6375 PACKAGE DESCRIPTION Please refer to http://www.linear.com/product/LT6375#packaging for the most recent package drawings. DF Package 14(12)-Lead Plastic DFN (4mm × 4mm) (Reference LTC DWG # 05-08-1963 Rev Ø) 1.00 BSC 3.00 REF 0.70 ±0.05 4.50 ±0.05 3.10 ±0.05 1.70 ±0.05 3.38 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 3.00 REF 4.00 ±0.10 (4 SIDES) 8 1.00 BSC 14 0.40 ±0.10 3.38 ±0.10 1.70 ±0.10 PIN 1 NOTCH 0.35 × 45° CHAMFER PIN 1 TOP MARK (NOTE 6) (DF14)(12) DFN 1113 REV 0 0.200 REF 7 R = 0.115 TYP 0.75 ±0.05 1 0.25 ±0.05 0.50 BSC BOTTOM VIEW—EXPOSED PAD 0.00 – 0.05 NOTE: 1. PACKAGE OUTLINE DOES NOT CONFORM TO JEDEC MO-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 6375fa For more information www.linear.com/LT6375 29 LT6375 PACKAGE DESCRIPTION Please refer to http://www.linear.com/product/LT6375#packaging for the most recent package drawings. MS Package 16 (12)-Lead Plastic MSOP with 4 Pins Removed (Reference LTC DWG # 05-08-1847 Rev B) 1.0 (.0394) BSC 5.10 (.201) MIN 0.889 ±0.127 (.035 ±.005) 3.20 – 3.45 (.126 – .136) 4.039 ±0.102 (.159 ±.004) (NOTE 3) 16 14 121110 9 0.50 (.0197) BSC 0.305 ±0.038 (.0120 ±.0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) 0.280 ±0.076 (.011 ±.003) REF 3.00 ±0.102 (.118 ±.004) (NOTE 4) 4.90 ±0.152 (.193 ±.006) DETAIL “A” 0° – 6° TYP 1 GAUGE PLANE 0.53 ±0.152 (.021 ±.006) DETAIL “A” 0.18 (.007) SEATING PLANE 1.10 (.043) MAX 0.17 – 0.27 (.007 – .011) TYP 3 567 8 1.0 (.0394) BSC 0.50 (.0197) BSC 0.86 (.034) REF 0.1016 ±0.0508 (.004 ±.002) MSOP (MS12) 0213 REV B 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 6375fa 30 For more information www.linear.com/LT6375 LT6375 REVISION HISTORY REV DATE DESCRIPTION PAGE NUMBER A 12/15 Added A-grade. 1-7, 15, 19 6375fa 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 representaFor more information www.linear.com/LT6375 tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. 31 LT6375 TYPICAL APPLICATION Bidirectional Full Range Current Monitor VS = 5V (OR 2V GREATER THAN VMON) –REFA –REFB –REFC 19k 38k 23.75k V+ 190k VMON = 0V TO 3V –IN 190k +IN 190k RSENSE – OUT VOUT = VREF + 24 • (VSENSE) + REF LOAD 19k 38k +REFA +REFB 23.75k +REFC 190k SHDN VREF = 1.25V V– 6375 TA06 NOTE: OPERATES OVER FULL RANGE OF LOAD VOLTAGE RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1990 ±250V Input Range Difference Amplifier 2.7V to 36V Operation, CMRR > 70dB, Input Voltage = ±250V LT1991 Precision, 100µA Gain Selectable Amplifier 2.7V to 36V Operation, 50μV Offset, CMRR > 75B, Input Voltage = ±60V LT1996 Precision, 100µA Gain Selectable Amplifier Micropower, Pin Selectable Up to Gain = 118 LT1999 High Voltage, Bidirectional Current Sense Amplifier –5V to 80V, 750 µV, CMRR 80dB 100kHz Gain: 10V/V, 20V/V, 50V/V LT6015/LT6016/ LT6017 Single, Dual, and Quad, Over-The-Top Precision Op Amp 3.2MHz, 0.8V/µs, 50µV VOS, 3V to 50V VS, 0.335mA IS, RRIO LTC6090 140V Operational Amplifier 50pA IB, 1.6mV VOS, 9.5V to 140V VS, 4.5mA IS, RR Output LT6108 High Side Current Sense Amplifier with Reference and Comparator with Shutdown 2.7V to 60V, 125µV, Resistor Set Gain, ±1.25% Threshold Error LT1787/ LT1787HV Precision, Bidirectional High Side Current Sense Amplifier 2.7V to 60V Operation, 75μV Offset, 60μA Current Draw LTC6101/ LTC6101HV High Voltage High Side Current Sense Amplifier 4V to 60V/5V to 100V Operation, External Resistor Set Gain, SOT23 LTC6102/ LTC6102HV Zero Drift High Side Current Sense Amplifier 4V to 60V/5V to 100V Operation, ±10μV Offset, 1μs Step Response, MSOP8/DFN Packages LTC6104 Bidirectional, High Side Current Sense 4V to 60V, Gain Configurable, 8-Pin MSOP Package 6375fa 32 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 For more information www.linear.com/LT6375 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LT6375 LT 1215 REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2015