Date: 06/09/2012

Driver ICs for mains powered LED-lamps feature flicker-free digital dimming

The new 120/230 Volts AC mains powered LED drivers iW3616 and iW3617 from iWatt Inc feature flicker free dimming even from residential TRIAC dimmers and also sophisticated digital dimmers. Greatech Industrial Co., LTD., has already designed the iW3616 into its new LED lighting fixture line. The advantage of these LED drivers as per Mr. Brian Wu, Technical Director at Shenzhen Greatech Industrial Co., LTD. is not only the performance but also the cost.

iW3616 and iW3617 designed to meet safety and other regulations world-over. Achieving power factor greater than 0.95 and low total harmonic distortion (THD) of less than 15%. Both devices are designed to meet, or exceed the 85% efficiency required for most new LED driver designs.

iW3616 and iW3617 offer output power ratings up to 12W and 25W, respectively. They feature flickerless technology to eliminate flicker, along with iWatt’s patented digital dimming algorithms.

The iW3616 and iW3617 enable a 10% to 20% savings in BOM cost and a smaller overall solution size compared to the iWatt's previous iW3614. This is achieved by replacing FETs with lower cost BJTs, by reducing the component count needed for the protection circuit and EMI filtering, and by using a smaller, lower-cost E-capacitor.

The iW3616 and iW3617 operate with dimming frequencies from 630Hz to 900Hz and allow smooth, flicker-free dimming from 1% to 100% with tight +/-5% LED current regulation. Comprehensive safety features include: LED open/short circuit protection, input over-voltage protection, over-temperature thermal shutdown, and AC line over-voltage/frequency protection. An LED current de-rating at high temperatures also protects LEDs.

iW3616, iW3617 meet global standards, including European Union IEC61000-3-2(1) requirement, complies with NEMA SSL 6(2) dimming standard for incandescent replacement screw-base lighting retrofit, and compatible with Zhaga(3) hot-plug LED module for LED light interchangeability.

The iW3616 and iW3617 are available now in production quantities. They come in a standard, 14-lead SOIC package. Samples are available at $0.77 for the iW3616 and $0.91 for the iW3617, both in 1000-piece quantities.