The HV9911DB1v2 is an LED Driver capable of driving up to 20 one-watt LEDs in series from an input of 21 27V DC. The demoboard uses Supertex`s HV9911 in a boost topology. The converter has a very good initial regulation (+/-5%) and excellent line and load regulation over the entire input and output voltage range (<+/- 1%). The full load ef
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ciency of the converter is typically greater than 90%. The HV9911DB1v2 is also protected against open LED and output short circuit conditions. It is also protected under input undervoltage conditions by limiting the input current. It has an excellent PWM dimming response, with typical rise and fall times less than 2 s, which will allow high PWM dimming ratios. The switching frequency of the HV9911DB1v2 CAN be synchronized to other HV9911 boards or to an external 200kHz Clock by connecting the Clock to the SYNC pin of the HV9911DB1v2. The HV9911DB1v2 includes and RC lter to prevent false triggering of the short Circuit Protection during PWM dimming, which was noticed with the HV9911DB1. This improvement makes the HV9911DB1v2 immune to turn-on current spikes in most cases. For a detailed explanation of the origin of the turn-on spike and the effect of the RC lter on the short circuit response time, please refer to the HV9911 datasheet. 2. 2uF, 25V, X7R ceramic chip capacitor SMD1210 TDK Corp C3225X7R1H225K
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