Third-generation LED drivers feature flickerless technology and digital dimming control

September 03, 2012 // By Paul Buckley
iWatt Inc., has unveiled the latest digital AC/DC SSL (solid state lighting) LED driver platform with the iW3616 and iW3617.

The platform expands iWatt’s existing line of Flickerless LED drivers, increasing output power to 2 W or higher, lowering the bill of materials (BOM) cost by 10% to 20%, and offering compatibility with an even wider range of installed dimmers, including residential TRIAC dimmers as well as the more sophisticated digital dimmers.

Regulations around the world mandate driver performance, as well as efficiency. Quality is specified in terms of total harmonic distortion (THD) and power factor and the iW3616 and iW3617 easily exceed all requirements, 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.

Designed for 120 V/230 VAC offline LED lighting bulbs and fixtures, the iW3616 and iW3617 offer output power ratings up to 12 W and 25 W, respectively. They combine iWatt’s PrimAccurate technology to reduce BOM cost and size, with Flickerless technology to eliminate flicker, along with iWatt’s patented digital dimming algorithms.

The iW3616 and iW3617 build on iWatt’s popular 15 W iW3614 LED driver by expanding dimmer compatibility, and improving dimming and EMI performance. They enable a 10% to 20% savings in BOM cost and a smaller overall solution size compared to the 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 630 Hz to 900 Hz 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.

Availability and Pricing

The iW3616 and iW3617 are available now in production quantities. They come in a standard, 14-lead