ISL78100 Intersil Corporation, ISL78100 Datasheet
ISL78100
Related parts for ISL78100
ISL78100 Summary of contents
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... Data Sheet High Power LED Driver The ISL78100 is a high-power LED backlight driver with an integrated 36V FET designed to drive high-power LEDs in series. The PWM converter runs from an internally generated 1MHz clock. With efficiencies over 90%, the regulator provides tight control of LED current and may be configured in either boost or buck topologies, allowing from series diodes to be driven from wide input voltages ...
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... V Light Control Voltage Linear Input LEVEL Range FB Feedback Undervoltage Fault UV FAULT 2 ISL78100 Thermal Information = +25°C) Thermal Resistance 20 Ld QFN Package (Notes 1, 2 Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . +135°C Storage Temperature . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C Pb-free reflow profile . . . . . . . . . . . . . . . . . . . . . . . . . .see link below http://www.intersil.com/pbfree/Pb-FreeReflow.asp ...
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... Schottky . MODE TEMP 1 (VDC - 0.25) > V > 0.25V Standard Mode light level to PWM modulation of EN/PWM input; LED bias current determined by Don’t Care V < 0.25V 0 V < (VDC - 0.25) 3 ISL78100 = 12V 5V -40°C to +105°C unless otherwise specified. (Continued CONDITIONS V = 1V, EN/PWM = 3V LEVEL ...
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... LEDs @ 10kHz 150 100 50 5 LEDs @ 10kHz PWM DIMMING DUTY CYCLE (%) FIGURE 5. LEDs PWM DIMMING LINEARITY 4 ISL78100 99%@10kHz 10%@10kHz 10%@100Hz FIGURE 2. 5 LEDs EFFICIENCY vs INPUT VOLTAGE vs 99%@10kHz 10%@100Hz 8 10 FIGURE 4. 8 AND 5 LEDs EFFICIENCY vs PWM DUTY CYCLE ...
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... PWM @ 10kHz 365 360 (V) IN FIGURE 11. 3 LEDs LINE REGULATION OF PWM DUTY CYCLE OF 99% 5 ISL78100 (Continued FIGURE 8. 3 LEDs CURRENT ACCURACY vs INPUT VOLTAGE 420 415 410 405 400 395 390 385 380 375 370 ...
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... LED 0 0 0.2 0.4 0.6 V (V) LEVEL FIGURE 15. LED CURRENT LEDs I = 350mA LED FIGURE 17. START-UP WAVEFORMS 6 ISL78100 (Continued FIGURE 14. 3 LEDs LINE REGULATION OF PWM DUTY 0.1000 0.0100 8 LED 0.0010 0.0001 0.8 1.0 BIAS FIGURE 16. QUIESCENT CURRENT (NON-SWITCHING) LEVEL VIN ...
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... FIGURE 19. 50% PWM DIMMING AT 100Hz 8 LEDs V = 12V IN PWM = 1kHz FIGURE 21. 10% PWM DIMMING AT 1kHz TRANSIENT RESPONSE WHEN LOAD DYNAMICALLY CHANGES FROM 8 LEDs TO 7 LEDs 8 LEDs V O FIGURE 23. TRANSIENT RESPONSE OPERATES FROM LEDs 7 ISL78100 (Continued VOUT (AC COUPLED VOUT (AC COUPLED) FB FIGURE 22 ...
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... Typical Performance Curves FIGURE 25. OVP AND RESET Typical Boost Mode Application Diagram V BAT V DC 0.1µF TEMP SENSOR FIGURE 27. TYPICAL BOOST MODE APPLICATION CIRCUIT 8 ISL78100 (Continued) VOUT 8LEDs V I LED VIN VHI FAULT SWD1 VBAT SWD2 VDC OVP BUCK/BOOSTN TEMP SWS1 ...
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... Ground return and FB ground reference 19 FAULT Gate drive of fault protection FET. Driven low under fault conditions 20 VIN Input supply 9 ISL78100 DESCRIPTION for input voltages less than 5V. LDO output can also be biased with IN is <5.5V. A minimum of 3.3µF decoupling capacitor is needed in this pin <5.5V IN FN6626 ...
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... V START CLK INNER LOOP R AMP PWM CONTROL HALT LEVEL (T) AND CURRENT LIMIT LOAD TEMPERATURE CURRENT COMPENSATION SENSE TEMP TMAX FIGURE 28. ISL78100 BLOCK DIAGRAM VDC VHI CLOCK AND RAMP GENERATOR REF CLK R AMP OVP SWD2 SWD1 SWS1 FET CURRENT SENSE SWS2 V DC ...
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... Figure 28 shows a block diagram of the system. Application Configurations Operating Modes The ISL78100 can operate as either a buck or boost regulator. Hardwire BUCK/BOOSTN to GND for boost mode or to VDC for buck mode. In buck mode the power NDMOS drive circuit is "floated" (boot-strapped) allowing the NDMOS gate to be driven above VIN to fully enhance the power NDMOS ...
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... VBAT and VIN directly together. All faults except input supply overvoltage latch the ISL78100 into an off-state that can be cleared by either power cycling the input supply or the EN/PWM pin. Connecting the TMAX pin to VDC disables the fault latch function (LED over-temperature control is also disabled) ...
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... FB LEVEL CURRENT TEMPERATURE COMPENSATION ISL78100 FIGURE 34. OVER-TEMPERATURE CIRCUIT 13 ISL78100 Component Selection Input Capacitor Switching regulators require input capacitors to deliver peak VOUT charging current and to reduce the impedance of the input COUT supply. This reduces interaction between the regulator and 20µF input supply, improving system stability. The high switching ...
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... Care should be taken to ensure the voltage rating of the capacitor exceeds the maximum output voltage. Compensation The ISL78100 employs a direct summing control loop with current feedback. No error amplifier is used in the system. The arrangement provides fast transient response and makes use of the output capacitor to compensate the loop. ...
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... SWS1,SWS2 to the inductor in buck mode - from C to PGND OUT • Feedback signals levels are small to improve efficiency. Ensure the reference connection (GND or VIN) between the sense resistor and IC pin doesn't carry switching current. 15 ISL78100 VOUT (V) 7 10.5 LED’ Ceramic DMIN ...
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... Boost Mode Application Diagram V BAT Boost Mode with Overcurrent Fault and LED Temperature Protections Application Diagram V BAT TEMP SENSOR V FIGURE 36. BOOST MODE APPLICATION WITH OVERCURRENT FAULT PROTECTION AND LED TEMPERATURE PROTECTION 16 ISL78100 VIN VHI FAULT SWD1 VBAT SWD2 OVP VDC SWS1 TEMP SWS2 TMAX ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 17 ISL78100 VIN VHI FAULT ...
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... Automotive Applications The LED load and ISL78100 may be protected against load dumps and other electrical faults in automotive supplies with a minor addition to the standard application schematic: • A reverse transient automotive-rated protection power Schottky must be added in series with the input supply • A 500Ω current limit resistor must be inserted in series with the VBAT pin • ...
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... L20.4x4C 20 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE Rev 0, 11/06 4.00 6 PIN 1 INDEX AREA 0.15 (4X) TOP VIEW ( 3. 8 TYP ) ( TYPICAL RECOMMENDED LAND PATTERN 19 ISL78100 16X 20X 0.4 ± 0.10 BOTTOM VIEW BOTTOM VIEW ± 20X 20X 20X NOTES: 1 ...