LED Driver Enables High Power Factor Retrofit LED Lamps

The AP1684 from Diodes Incorporated is a power factor-corrected AC-DC LED driver suiting a variety of offline LED lamp types, including E26, GU10, PAR and T8.  Using pulse-frequency modulation technology and operating in boundary-conduction mode, this device provides tight current regulation to an accuracy of ±2%, while achieving a power factor of .97 and THD of less than 20%.

Helping to significantly reduce circuit BOM cost, this primary-side driver removes the need for opto-coupler, secondary-side control and loop-compensation circuitry.  Driving an external bipolar junction transistor, the AP1684 requires only a small external component count and coupled with its SO8 packaging, enables lamp designers to reduce PCB footprint, increase power density and raise overall product reliability.

The driver keeps start-up and operating currents low and uses dynamic base driver control and valley-mode switching to minimize transition loss and achieve high efficiency, typically 93%.  The AP1684’s circuit protection features are comprehensive and include over-voltage, short-circuit and over-temperature facilities.

The AP1684 high power-factor LED driver from Diodes Incorporated is priced at $0.18USD each in quantities of up to 50k.