New Industry Products

iWatt Introduces Primary Side Regulated Digital PWM Controller for Dimmable LED Lighting

November 24, 2009 by Jeff Shepard

iWatt, Inc. announced the release of the iW3610 Digital Controller for dimmable LED lighting applications. It is said to be the industry’s first digital LED driver IC with primary side regulation, which eliminates the need for an opto-coupler thereby reducing bill-of-material costs and increasing the mean time between failure (MTBF). The iW3610 eliminates flicker and improves efficiency and reliability for dimmable LED lights of 25W or lower wattage.

The iW3610 uses advanced digital control technology to automatically detect and operate seamlessly with a leading edge or a trailing edge dimmer or if no dimmer is present. In case of an un-supported dimmer, the device shuts down and goes into a fail-safe mode. The device is compatible with existing wall dimmers available worldwide and allows parallel lamp operation for true retrofit replacement of incandescent bulbs, halogen lamps and linear fluorescent tubes. The iW3610 operates in quasi-resonant mode and employs adaptive gate drive control and iWatt’s proprietary EZ EMI technology to achieve high efficiency and a low EMI signature.

Depending on the application, efficiencies greater than 80% and power factor greater than 0.9 are easily achievable. The iW3610’s maximum operating frequency of 200kHz enables LED designers to use smaller size components to design driver boards that are small enough to fit inside existing bulb and lamp housing or inside fluorescent tubes. In addition to the standard protection features, the iW3610 also provides over-temperature protection using an external NTC resistor for robust protection. Moreover, the IC provides temperature drift control of the LED driver current to ensure that the LEDs will never operate outside of their recommended safe operating area.

iWatt also announced that Everlight, a leader in LED lighting products in Taiwan has chosen the iW3610 for their products’ lighting applications.

"We evaluated several ICs for our LED dimming products and iW3610’s advantages included the lowest BOM cost, one of the best performances and it worked with all of the dimmers we tested. It will be difficult to find another competitor that can match theiW3610 so for Everlight it was a very simple decision to select iWatt," said Allen Lee, Director of the Lighting Business Unit from Everlight.

"Thanks to digital control technology, we are able to move the LED lighting industry one step closer to meeting the consumer’s desire for true retrofit lamp replacements that save energy, work with existing dimmers all for a competitive price. The iW3610 dimmable LED driver gives systems design engineers the technology and tools to improve reliability, reduce heat loss and fit the LED driver board into the most space constrained lamp housing while driving down the bill-of-material cost," said Zahid Rahim, Vice President and General Manager of iWatt’s AC-DC Business Unit.

Key features of the iW3610 include: isolated ac-dc offline 110V/230V (required by many LED lamp OEMS); external power MOSFET drive allows scalable 5 to25W output power; primary-side regulation eliminates opto-isolator and improves reliability; intelligent wall dimmer detection; wide dimming range from 2 to 100%; power factor over 0.9 without dimmer; LED current de-rating at high temperatures protects LEDs; thermally enhanced SO-8 package with exposed pad allows high ambient temperature operation at 110°C PCB temperature; up to 200kHz switching frequency allows small size design; multiple protection features: LED open/short circuit protection, input under-voltage/over-voltage protection and over-temperature thermal shutdown; and meets or exceeds EN55015B, IEC61000-3-2 regulatory standards with sufficient margin.

Samples of the iW3610 are currently available. Pricing is $0.98 per 1,000 unit quantity.