HV9918 Supertex, HV9918 Datasheet
HV9918
Related parts for HV9918
HV9918 Summary of contents
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... Additional features include thermal-shutdown protection. The high switching frequency up to 2.0MHz permits the use of small inductors and capacitors, minimizing space and cost in the overall system. The HV9918 comes in a small 8-Lead DFN package and is ideal for industrial and general lighting applications. R SENSE ...
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... C* unless otherwise noted) O Max Units Conditions - input voltage - 5 6.0 to 40V GND - 750 µA DIM < 0. 4.5V 4.5V 2.0 MHz --- - 4 rising falling ● Tel: 408-222-8888 ● www.supertex.com HV9918 GND VDD 6 DIM 5 θ C 4.0V DD ...
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... V --- - 0.7 V --- DIM rising edge 0.9 • DIM falling edge 0.1 • 0.7 A --- 2.0 Ω --- - µ 40V IN - ºC --- - ºC --- - 260 C = 47nF RAMP Hz - 1100 C = 10nF RAMP - V --- - 2.1 V --- - 35 mV --- = ● Tel: 408-222-8888 ● www.supertex.com HV9918 +70mV to RS(HI) IN -70mV to RS(LO ...
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... VDD is the output of a 5.0V regulator capable of sourcing 8mA. Bypass VDD to GND with a 1.0μF capacitor. DIM Input The HV9918 allows dimming with a PWM signal at the DIM input. A logic level below 0.7V at DIM halts SW switching, turning the LED current off. To turn the LED current back on, the logic level at DIM must be at least 2 ...
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... CS. Disregarding the effect of the propagation delays, the sense resistor can be calculated as RS(HI) RS(LO) R ≈ • SENSE 2 I LED Selecting Buck Inductor L The HV9918 regulates the LED output current using an input comparator with hysteresis (Figure 2). As the current through www.DataSheet4U.com t DPDL I V LED RS(HI) R SENSE V RS(LO) R SENSE ...
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... Thermal Shutdown The HV9918 thermal-shutdown feature turns off the SW driv- er when the junction temperature exceeds +140°C. The SW driver turns back on when the junction temperature drops 60°C below the shutdown temperature threshold. Freewheeling Diode Selection The forward voltage of the freewheeling diode should be as low as possible for better effi ...
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... No responsibility is assumed for possible omissions and inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications refer to the ©2009 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Doc.# DSFP-HV9918 A122109 E Note 1 (Index Area D/2 x E/2) θ ...