Dialog Semiconductor

Demoboard LED driver_36V300mA_MR16_IW3662

Low Voltage (12VAC) Dual-Mode Digital Control Dimmable LED Driver

Topology: Other

Original publication on 2016-02-19, revision 1.2


The iW3662 advanced digital LED driver, designed for low voltage AC and DC input voltages, combines support for both low voltage LEDs and high voltage Chip-On-Board(COB) LED modules at power levels up to 8W.The iW3662 features two selectable operating modes to accommodate both low voltage LEDs and high voltage COB LEDs in one part. The Boost-Buck mode provides a boost converter to step-up the input voltage to an intermediate voltage, which a second buck regulator stage steps down to create a highly efficient, constant current LED controller. The Boost-Linear mode, designed to work with high voltage COB LEDs, steps up the input voltage to a higher voltage than in the Boost-Buck mode, then, with the buck converter now disabled and reconfigured into a linear current regulator, provides a highly accurate constant current sink to drive the LEDs.The highly configurable digital control circuitry allows the enduser to specify one part for multiple applications, coveringthe bulk of low voltage LED replacement bulb applications.Using Dialog’s Flickerless™ technology allows the iW3662to operate without visible flicker and operate with a broadrange of input dimmer types (leading edge, trailing edgeand digital) while effectively detecting and managing bothelectronic and magnetic transformers automatically. Whenthe iW3662 detects a magnetic transformer, an additionaloutput drives an external switch that can add extra inputcapacitance needed to ensure proper operation, easingthe design of replacement bulbs compatible with bothtransformer types.The iW3662 also integrates an internal bleeder FET to add adynamic load to the input to optimize electronic transformerperformance during low dimming ranges. Also, full protectionfeatures including over-temperature protection derating,which lowers the output current drive to the LEDs whenan over-temperature event occurs to maintain light outputeven during a fault condition, provides robust and functionalsolutions for low voltage LED replacement lighting.


  • ● 10 to 24VDC input voltage or 12VAC input voltage● Output power up to 8W● Supports magnetic or electronic transformers● Two operational modes:xx Boost-Buck
  • low voltage LED arraysxx Boost-Linear
  • high voltage COB LEDs● Integrated boost controller and buck/linear currentregulator controller● Flickerless™ technology for flicker-free LED dimming● Wide dimmer compatibility (leading edge, trailing edge,and digital)● Deep dimming to 5% (depends on dimmers)● Power factor > 0.7● Tight LED current regulation (+/- 5%) in both modes● Optimized dimming curve for maximizing dimmer andelectronic transformer compatibility● Over-temperature protection derating● OVP, OCP, and open load protection● 16-lead QFN (4x4mm) or 16-lead TSSOP


  Order Code SPEC Product series L
RDC typ.
RDC max.
Bauform Version Samples
7447779218 PDF
7447779222 PDF
7447779127 PDF WE-PD SMT Power Inductor 27 1.24 1.55 120 150 15 7345 Robust
7447779122 PDF WE-PD SMT Power Inductor 22 1.41 1.7 90 110 17 7345 Robust
744771156 PDF

Other applications and Würth Elektronik products for this IC

  • iW3662
    Topology: Boost, Input Voltage (min.): 12.00 V, Input Voltage (max.): 12.00 V, Output 1: 36.00 V / 0.300 A