ISL97675 Intersil Corporation, ISL97675 Datasheet
ISL97675
Related parts for ISL97675
ISL97675 Summary of contents
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... LED Driver with Phase Shift Control ISL97675 The ISL97675 is an LED driver that drives 4 channels of low power LEDs from 4.5V to 26V input and up to 45V output. The ISL97675 compensates for non-uniformity of the forward voltage drops in the LED strings with its 4 voltage controlled-current source channels ...
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... COMP GM AMP + - ISET REF OVP REF VSC GND PHASE SELECT PWM 8-BIT DIGITIZER FPWM/DirectPWM DIRECTPWM DETECT OPTIONAL PFET 10µH/3A FAULT ISL97675 FAULT O/P SHORT FET DRV FET LOGIC DRIVER Σ IMAX ILIMIT FPO 8-BIT DYNAMIC HIGHEST VF DAC HEADROOM STRING CONTROL DETECT VSET ...
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... ISL97675 ISL97675 (20 LD QFN) TOP VIEW VDDIO ISL97675 4mmx4mm ISET Decouple with capacitor for internally generated supply rail. I Enable I FSW = 0 ~ 0.25 * VDDIO, Boost Switching Frequency = 600kHz with phase shift. FSW = 0.25 * VDDIO ~ 0.5 * VDDIO, Boost Switching Frequency = 600kHz without phase shift ...
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... SnPb and Pb-free soldering operations). Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 3. For Moisture Sensitivity Level (MSL), please see device information page for ISL97675. For more information on MSL please see techbrief TB363. ...
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... Open Circuit Protection (OCP) ............................................................................................................ 15 Overvoltage Protection (OVP) ............................................................................................................ 15 Undervoltage Lockout ....................................................................................................................... 15 Master Fault Protection ..................................................................................................................... 15 Over-Temperature Protection (OTP).................................................................................................... 15 Components Selections ..................................................................................................................... 17 Input Capacitor................................................................................................................................ 17 Inductor ......................................................................................................................................... 18 Output Capacitors ............................................................................................................................ 18 Channel Capacitor ............................................................................................................................ 18 Output Ripple .................................................................................................................................. 18 Schottky Diode ................................................................................................................................ 18 Applications....................................................................................................................................... 19 High Current Applications .................................................................................................................. 19 Revision History ................................................................................................................................ 19 Products ............................................................................................................................................ 19 Package Outline Drawing .................................................................................................................. 20 5 ISL97675 www.DataSheet4U.com FN7630.0 May 19, 2010 ...
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... Low Voltage EN Guaranteed Range for EN Input High Hi Voltage t EN Low Time before Shut-Down ENLow 6 ISL97675 Thermal Information (T = +25°C) A Thermal Resistance (Typical QFN Package (Notes Thermal Characterization (Typical QFN Package (Note Maximum Continuous Junction Temperature . . . . . . +125°C Storage Temperature . . . . . . . . . . . . . . . -65°C to +150°C Pb-free reflow profile ...
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... PWMI Input Frequency Range PWMACC PWMI Input Accuracy PWMHYST PWMI Input Allowable Jitter Hysteresis PWM GENERATOR FPWM PWM Dimming Frequency Range VRFPWM Voltage at RFPWM pin tDIRECTPWM Direct PWM Minimum On Time 7 ISL97675 = +25° 12V 3.3V MIN CONDITION (Note 8) 1 +25°C A 100% LED Duty Cycle ...
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... Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization and are not production tested minimum V of 4.5V, the maximum output is limited by the 28V but minimum V can be lower at lower V OUT OUT D . MIN 8 ISL97675 = +25° 12V 3.3V MIN CONDITION (Note 8) 3.15 1 12V 8 IN ...
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... FREQUENCY AT 20mA for 4P12S (100% LED DUTY CYCLE) 100 +25°C 90 -40° +85° (V) IN FIGURE 5. EFFICIENCY TEMPERATURE AT IN 20mA 9 ISL97675 100 80 24V FIGURE 2. EFFICIENCY vs 30mA LED CURRENT IN 100 80 20mA/1.2MHz ...
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... V (V) IN FIGURE TEMPERATURE AT HEADROOM IN 20mA FIGURE 11. IN-RUSH AND LED CURRENT AT V FOR 4P12S AT 20mA/CHANNEL 10 ISL97675 (Continued 4. FIGURE 8. QUIESCENT CURRENT -40° FIGURE 10 FIGURE 12. IN-RUSH AND LED CURRENT www ...
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... FIGURE 13. LINE REGULATION WITH V FROM 6V TO 26V 20mA/CHANNEL FIGURE 15. LOAD REGULATION WITH I FROM 0% TO 100% PWM DIMMING 12V, 4P12S AT 20mA/CHANNEL IN FIGURE 17. ISL97675 SHUTS DOWN AND STOPS SWITCHING ~ 30ms AFTER EN GOES LOW 11 ISL97675 (Continued) CHANGE FIGURE 14. LINE REGULATION WITH 12V, 4P12S AT CHANGE FIGURE 16 ...
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... If there is no signal longer than 28ms, the device will enter shutdown. Power Sequence There is no specific power sequence requirement for the ISL97675. The EN signal can be tied to V VDDIO as it will prevent the device from powering up. 12 ISL97675 Current Matching and Current Accuracy Each channel of the LED current is regulated by the current source circuit, as shown in Figure 18 ...
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... FIGURE 22. EQUAL PHASE SHIFT LED DRIVERpwm 10 15 Phase Shift Control The ISL97675 is capable of delaying the phase of each current source. Conventional LED drivers pose the worst load transients to the boost circuit by turning on all channels simultaneously as shown in Figure 19. In contrast, the ISL97675 phase shifts each channel by turning them on once during each PWM dimming period as shown in Figure 20 ...
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... D1 FPWM 255 66 × --------- - = D2 FPWM 255 where t is the sum of t and t FPWM ON of active channels. The ISL97675 will detect the numbers of active channels automatically and is illustrated in Figure 23 for 4-channel. t PWMIN 60% PWMI FPWM PWMOUT t OFF t ON ILED1 40% 60% ...
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... Due to the lag in boost response to any load change at its output, certain transient events (such as LED current steps or significant step changes in LED duty cycle) can transiently look like LED fault modes. The ISL97675 uses feedback from the LEDs to determine when stable operating region and prevents apparent faults during these transient events from allowing any of the LED stacks to fault out ...
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... FB1 Short Circuit Upper OTP not triggered but FB1 > FB1 Open Circuit Upper OTP not triggered with infinite and FB1 < 4V resistance 16 ISL97675 For the extensive fault protection conditions, please refer to Figure 24 and Table 3 for details. LX O/P SHORT OVP FET LOGIC DRIVER ...
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... V ⁄ – ISL97675 TABLE 3. PROTECTIONS TABLE (Continued) FAILED CHANNEL ACTION FB1 remains ON and has highest VF, thus V OUT increases. All channels go off until chip cooled and then comes back on with current reduced to 76%. Subsequent OTP triggers will reduce I ...
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... Equation 17. Fora given inductor size, the larger the inductance value, the higher the series resistance because of the extra number of turns required, thus, higher conductive losses. The ISL97675 current limit should be less than the inductor saturation current. Output Capacitors The output capacitor acts to smooth the output voltage and supplies load current directly during the conduction phase of the power switch ...
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... Applications High Current Applications Each channel of the ISL97675 can support up to 40mA. For applications that need higher current, multiple channels can be grouped to achieve the desirable current. For example, the cathode of the last LED can be connected to FB1 to FB2, this configuration can be treated as a single string with 80mA current driving capability ...
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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 (4X) 0.15 TOP VIEW ( 3. 8 TYP ) ( TYPICAL RECOMMENDED LAND PATTERN 20 ISL97675 16X 20X 0.4 ± 0.10 BOTTOM VIEW BOTTOM VIEW ± 20X SIDE VIEW ( 20X 20X 0 ...