High-efficiency, rugged IC without bleeders, drives bulbs, tubes, and lighting fixtures up to 22W

Power Integrations announced the LYTSwitch™-7, a family of single-stage, non-isolated, TRIAC dimmable, buck topology LED driver ICs.

The company stated that this high-efficiency device is suitable for light bulbs, tubes, and lighting fixtures because it can support up to 22W with an ultra-small SO-8 footprint without a heatsink. The LYTSwitch-7 design does not require a bleeder. It reduces the number of components to 20 by utilizing simple passive damping for TRIAC management and off-the-shelf single-wound inductors.

The LYTSwitch-7IC provides a Phase Cut (TRIAC) dimming solution capable of a wide dimming range and monotonic dimming response. This LED driver achieves an efficiency of over 86%, which is 2% higher than conventional dimmable products, and offers high power factor (PF), precise regulation, and comprehensive protection features. It is suitable for low or high-line input designs, as well as a wide range of universal input designs for US commercial lighting applications operating at 90VAC – 305VAC, enabling TRIAC dimming in low-line installations.

Hubertus Notohamiprodjo, Product Marketing Director at Power Integrations, said, “The new LYTSwitch-7 LED driver IC provides a very robust solution and reduces the number of components by about 40% compared to existing circuits. “The built-in 725V MOSFET provides better durability during line surges, and the bleeder-free design enables the implementation of a more efficient and reliable driver because it does not generate unnecessary heat along with high TRIAC compatibility,” he said.

Like all other LED drivers from Power Integrations, the LYTSwitch-7 IC also provides various protection features, such as thermal foldback with end-stop shutdown, which protects the IC, driver, and lighting fixture at abnormally high ambient temperatures by automatically reducing current and dimming the lamp.

Because the IC automatically limits abnormal temperature changes without turning off the lamp, developers recognize that thermal foldback is a key factor in reducing costs associated with the over-design of electrical and mechanical components to meet reliability targets. The device is also protected against open and short circuits, input and output 0V, overcurrent, and SOA. The LYTSwitch-7 IC meets international standards, including the following.

Major applications include low-cost A19 lamps, small form factor lamps such as candle-style and GU10 bulbs, commercial and industrial applications, ceiling lamps, and downlight fixtures.