Dual over-temperature protection (internal, and external sensor) – single wire NTC connection.Calibrated internal voltage reference and temp.Hardware DD mode option on high mode without current limit.
Led flashlight driver circuit s 1703 drivers#
Very low internal resistance comparable to best DD drivers.Lower losses in springs, wires, switch compared to PWM drivers.Higher overall lm/W efficiency on lower modes compared to PWM drivers.Longer run-times on lower modes compared to PWM drivers.Completely silent – no acoustical or EMI noise („whining“).Available as 3, 6, 9 and 12Amps version – 2-12Amps possible by adjusting current in UI.True PWM-less constant current (all modes).
Led flashlight driver circuit s 1703 series#
“MOSLED” high performance metal core PCBs have space for MOSFET and NTC sensor, which makes triple or quad LED builds fast and easy, and more important – reliable because of real constant current driving/limiting.īecause current on all modes is regulated, LD-x4 driver series is ideal solution for driving modern LEDs with very low Vf like Nichia 219C,319AT, Cree XP-L2,XP-G3, Luxeon V and Luminus SST-40 from 1S li-ion battery cells/pack. LD-B4 is designed to work with external power MOSFET (source of heat) for much higher power dissipation – up to which is more than enough for any triple or quad LED setup. LD-A4 is standard type of linear driver with all components on PCB, designed for power dissipation 2W Recommended applications are single Li-ion cell LED flashlights with single LED. This enables significantly longer run times on moonlight modes. Typical bleeding current is just 1mA, which is 5-10 times lower than conventional resistor bleeding.
Based on completely re-designed hardware and improved firmware, these drivers are optimized for single-cell (4.2V) flashlights, and offer some new features compared to LD-3, like hardware (real) direct drive mode option, 1-wire temperature sensor support, integrated moonlight with 3 levels (2.5mA, 5.0mA, 7.5mA) adjustable via user interface, and low current bleeding support for illuminated tailcap modules like ILC-1. LD-A4/B4 2-12A constant current („PWM-less“) LED drivers are next generation of LD driver series.