lt6109-1 Linear Technology Corporation, lt6109-1 Datasheet
lt6109-1
Related parts for lt6109-1
lt6109-1 Summary of contents
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... Two versions of the LT6109 are available. The LT6109-1 has the comparators connected in opposing polarity and the LT6109-2 has the comparators connected in the same polarity. In addition, the current sense amplifier and comparator outputs are directly accessible ...
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... LT6109-1/LT6109-2 ABSOLUTE MAXIMUM RATINGS (Note 1) + – Total Supply Voltage ( .................................60V Maximum Voltage (SENSELO, SENSEHI, OUTA) ............................... V + Maximum V – (SENSELO or SENSEHI) ....................33V Maximum EN/RST Voltage ........................................60V Maximum Comparator Input Voltage ........................60V Maximum Comparator Output Voltage......................60V Amplifier Input Current (Note 2)...........................–10mA SENSEHI or SENSELO Input Current .................... ± ...
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... SENSE I = 1mA OUT I = 100µA OUT + V = 2.7V 24mV Step, Output Rising Edge SENSE + V = 12V to 60V 100mV Step, Output Rising Edge SENSE V = 10mV to 100mV SENSE OUT LT6109-1/LT6109 2.7V 100Ω, EN/RST IN MIN TYP 2.7 l 475 600 –200 0.8 l –350 – ...
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... 10k, gain = 100, R OUT SYMBOL PARAMETER Reference and Comparator V Rising Input Threshold Voltage TH(R) (Note 10) (LT6109-1 Comparator 1 LT6109-2 Both Comparators) V Falling Input Threshold Voltage TH(F) (Note 10) (LT6109-1 Comparator – V (Note 5) HYS HYS TH(R) TH(F) Comparator Input Bias Current V Output Low Voltage OL High to Low Propagation Delay ...
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... Amplifier Gain Error Distribution 5mV TO 100mV SENSE 125 –0.048 –0.052 –0.056 –0.064 –0.060 GAIN ERROR (%) LT6109-1/LT6109-2 Performance characteristics taken 25.5k 2pF , unless Enable/Disable Response V EN/RST 2V/DIV 500µA/DIV 0µ ...
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... LT6109-1/LT6109-2 TYPICAL PERFORMANCE CHARACTERISTICS + + V = 12V 2.7V, R PULLUP EN/RST otherwise noted. (See Figure 3) Power Supply Rejection Ratio vs Frequency 160 140 120 100 100 1k 10k 100k 1M FREQUENCY (Hz) 610912 G09 System Step Response V SENSE 0.1V/DIV 0V V OUTA 1V/DIV 0V V OUTC1 ...
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... V (V) Comparator Input Bias Current vs Input Voltage –5 –10 –15 – 0.2 0.4 0.6 0.8 COMPARATOR INPUT VOLTAGE (V) LT6109-1/LT6109-2 Performance characteristics taken 25.5k 2pF , unless Hysteresis Distribution 30 25 –40°C 25° 110 125 3.0 4.6 6.2 7.7 9.3 10.9 12.5 14.1 COMPARATOR HYSTERESIS (mV) ...
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... LT6109-1/LT6109-2 TYPICAL PERFORMANCE CHARACTERISTICS + + V = 12V 2.7V, R PULLUP EN/RST otherwise noted. (See Figure 3) Comparator Output Leakage Current vs Pull-Up Voltage 23 18 125° –40°C AND 25°C – COMPARATOR OUTPUT PULL-UP VOLTAGE (V) 610912 G28 Comparator Step Response ...
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... PIN FUNCTIONS INC2 (Pin 7): Input of Comparator 2. For the LT6109-1 this is the noninverting input of comparator 2. For the LT6109-2 this is the inverting input of comparator 2. The other comparator input is internally connected to the 400mV reference. OUTA (Pin 8): Current Output of the Sense Amplifier. This pin will source a current that is equal to the sense voltage ...
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... LT6109-1/LT6109-2 BLOCK DIAGRAMS LT6109-2 SENSEHI 10 SENSELO 1 EN/RST 2 OUTC2 3 OUTC1 4 Figure 2. LT6109-2 Block Diagram (Comparators with the Same Polarity) APPLICATIONS INFORMATION The LT6109 high side current sense amplifier provides accurate monitoring of currents through an external sense resistor. The sensed voltage is amplified by an external resistor-set gain and level shifted from the positive power supply to a ground-referred output ...
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... A sense resistor with integrated Kelvin sense terminals will give the best results. Figure 3 illustrates the recommended method for connect- does not SENSE ing the SENSEHI and SENSELO pins to the sense resistor. LT6109-1/LT6109-2 value is determined, the mini- SENSE to 350µV. This SENSE SENSE of 100mV ...
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... LC 5 – V – OUT Figure 3. LT6109-1 Typical Connection IN will lower IN Figure 4. Shunt Diode Limits Maximum Input Voltage to Allow will result in faster Better Low Input Resolution Without Overranging . If low sense OUT Care should be taken when designing the board layout for ...
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... This error becomes less significant OUTA OUT as the value reduced if an external resistor, R shown in Figure 5, the error is then reduced to: V OUT(IBIAS) Adding R of the circuit as shown in Figure •I SENSE SENSE LT6109-1/LT6109-2 , Due to the Amplifier OUT(VOS OUT = V • SENSE SENSE ...
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... LT6109-1/LT6109-2 APPLICATIONS INFORMATION + LT6109 V BATT SENSEHI – R SENSE 1 SENSELO + + R IN – SENSE 5 + Figure 5. R Reduces Error Due Output Voltage Error, ∆V OUT(GAIN ERROR) External Resistors The LT6109 exhibits a very low gain error result, the gain error is determined primarily by the accuracy of the external resistors used to set the gain ...
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... OS V BATT SENSE I SENSE Figure 9. LT6109 Supply Current Monitored with Load OUTA 8 V OUT R OUT 610912 F07 Figure 10. Amplifier Output Voltage vs Input Sense Voltage ) BATT LT6109-1/LT6109-2 40.2V VALID SENSELO/ SENSEHI RANGE 20. LT6109 10 SENSEHI – OUTA 8 ...
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... If both comparator inputs are con- nected to the output then they must both be considered. Setting Comparator Thresholds The comparators have an internal precision 400mV refer- ence. In order to set the trip points of the LT6109-1 com- parators, the output currents the maximum output current ...
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... Figure 11. LT6109-1 1 SENSELO + – – EN/RST + V I OUTA + 3 OUTC2 – – V 400mV + REFERENCE OUTC1 – 5 – V – V LT6109-1/LT6109-2 OVER ( ) R1 UNDER I UNDER ( ) – I R1+ R2 MAX MAX I MAX ( ) 400mV –I R1 400mV UNDER < + OVER UNDER SENSEHI ...
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... V 10 SENSEHI – 1 SENSELO + + – OUTC2 400mV – R2 OUTC1 OUTC2 (LT6109-2) OUTC2 INCREASING (LT6109-1) V INC1 HYS HYS V TH (the actual internal threshold TH and the amplifier output current which you UNDER , is in addition HYS(EXTRA) HYS(EXTRA) I UNDER OUTA VTH INC2 ...
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... V LT6109 SENSEHI – 1 SENSELO + + – – 4 OUTC1 400mV + R2 Figure 14. Inverting Comparator with Added Hysteresis LT6109-1/LT6109-2 = 400mV •R1• + – +R3 = 410mV •R1• + ...
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... Typical Performance Characteristics. Load currents are conducted to the V range between 0V and 60V with respect the supply voltage used. As with any open-drain device, the outputs may be tied together to implement wire-OR logic functions. The LT6109-1 can be used as a single- output window comparator in this way. ...
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... B across R SENSE Gain Error: The gain error of the internal amplifier is a measure of how accurately the sense voltage is forced across R IN resulting error is 0.2% LT6109-1/LT6109-2 . The resulting current through This section will describe how various IN SENSE = 0.45% to the output IN 100Ω ...
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... V OUTC1 + EN/RST – V COMP 2 NOT SHOWN Figure 17. LT6109-1 Error Budget Configuration Accuracy of External Gain Set Resistors: The gain is set by external resistors R can external resistors contributes directly to the system error. IN Using 0.1% resistors results in the following error: 2 • 0.1% = 0.2% Drift of Gain Set Resistors: The drift of the external gain set resistors also contributes directly to the system er- ror ...
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... Total Amplifier Accuracy With External Resistors 2% Total Comparator And Reference Accuracy 2 • 0.1% 2 • 50ppm/°C • 100°C • 100 1 • • 50ppm/°C • 100°C • 100 Total Comparator And Reference Accuracy with External Resistors 4.7 LT6109-1/LT6109-2 also SENSE % ERROR 0.45 0.035 0.2 0.002 ...
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... The latching comparator outputs ensure the battery stays disconnected from the load until an outside source resets the LT6109 comparator outputs. MCU Interfacing with Hardware Interupts 0.1 TO LOAD 100 10 1 SENSEHI SENSELO OUT V OUTA ADC IN LT6109 RESET EN/RST INC2 3 6.65k OUTC2 4 6 OUTC1 INC1 – V 1.33k 5 ...
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... WHEN SUPPLY IS DISCONNECTED R6 487k The LTC6993-1 provides a 10µS reset pulse to the LT6109-1. The reset pulse is delayed by R7 and C1 whose time constant must be greater than 10ms and longer than the supply turn-on time. Optional components R8 and Q1 Simplified DC Motor Torque Control 100 ...
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... TYPICAL APPLICATIONS R8 100k 1 SECOND DELAY 10µs RESET PULSE ON START-UP TRIG OUT C1 LTC6994-1 0.1µF + GND SET DIV 191k 681k 487k 26 Precision Power-On Reset Using a TimerBlox 5V LT6109 100 10 SENSEHI R SENSE 1 SENSELO I LOAD R5 10k 3 OUTC2 R4 10k 4 OUTC1 GENERATOR 2 EN/RST TRIG OUT LTC6993-1 + ...
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... DETAIL “A” MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LT6109-1/LT6109-2 0.497 ± 0.076 (.0196 ± .003 REF 3.00 ± 0.102 (.118 ± .004) (NOTE 4) 0.86 (.034) REF 0.1016 ± 0.0508 (.004 ± ...
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... Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ADC Driving Application SENSE 0.1 LOW OUT 100 10 1 SENSEHI SENSELO OUTA 0.1µF LT6109 EN/RST INC2 3 OUTC2 6.65k 4 6 OUTC1 INC1 – V 1.33k 5 OVERCURRENT UNDERCURRENT COMMENTS 2.7V to 60V, 75µ ...