HV9918DB1 Supertex, HV9918DB1 Datasheet
HV9918DB1
Related parts for HV9918DB1
HV9918DB1 Summary of contents
Page 1
... Supertex inc. Hysteretic, Buck, High Brightness LED Driver with High-Side Current Sensing Features ► Hysteretic control with high-side current sensing ► Integrated 40V 1.0Ω MOSFET ► >90% Efficiency ► Wide input voltage range: 4.5 to 40V ► ±5% LED current accuracy ► ...
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... Switchingr frequency SW UVLO V Undervoltage lockout threshold DD ΔUVLO V Undervoltage lockout hysteresis DD * Guaranteed by design and characterization, 100% tested at T Supertex inc. Pin Description 8-Lead DFN 3.00x3.00mm body, 0.65mm pitch HV9918K7-G Product Marking Value -0.3 to +45V -0.3 to +6.0V -1.0 to +0.3V Thermal Resistance 1.6W = +25°C) -40° ...
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... Temperature hysteresis HYST Analog Control of PWM Dimming f Dimming frequency RAMP V RAMP threshold, Low LOW V RAMP threshold, High HiGH V ADIM offset voltage OS * Guaranteed by design and characterization, 100% tested at T Supertex inc. = 0.5Ω - +125 C* unless otherwise noted Min Typ 213 - 158 - - ...
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... The HV9918 includes a 3.7V under-voltage lockout (UVLO) with 500mV hysteresis. When V falls below 3.7V, switching disabled. Switching of SW resumes once V or higher. 5.0V Regulator VDD is the output of a 5.0V regulator capable of sourcing 8mA. Bypass VDD to GND with a 1.0μF capacitor. Supertex inc. REGULATOR + - CURRENT SENSE COMPARATOR + REF ...
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... RS(LO) R SENSE V DIM Supertex inc. the inductor ramps up and the voltage across the sense re- sistor reaches the upper threshold, the internal MOSFET at SW turns off. The MOSFET turns on again when the inductor current ramps down through the freewheeling diode until the voltage across the sense resistor equals the lower threshold ...
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... Open Drain Output of an internal 40V 1.0Ω MOSFET. TAB GND Must be wired to pin 7 on PCB. Supertex inc. PCB Layout Guidelines Careful PCB layout is critical to achieve low switching losses and stable operation. Use a multilayer board whenever pos- sible for better noise immunity. Minimize ground noise by connecting high-current ground returns, the input bypass capacitor ground lead, and the output fi ...
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... JEDEC Registration MO-229, Variation WEEC-2, Issue C, Aug. 2003. * This dimension is not specified in the JEDEC drawing. Drawings not to scale. Supertex Doc. #: DSPD-8DFNK73X3P065, Version C081109. (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to http://www.supertex.com/packaging.html.) does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives Supertex inc ...