New Industry Products

High-accuracy CV/CC LED Drivers for Smart Lighting and Ballasts

February 07, 2018 by Paul Shepard

Power Integrations has announced the LYTSwitch™-6 family of safety-isolated LED-driver ICs for smart lighting applications. The new ICs deliver flicker-free output up to 65 W, and feature up to 94% efficiency and as little as 15mW standby power, with configuration options for two-stage or single-stage PFC support.

Targeting smart residential and commercial fixtures and low-profile ceiling troffers, LYTSwitch-6 ICs also exhibit fast transient response, which facilitates excellent cross regulation performance of parallel LED strings without additional regulator hardware, and allows easy-implementation of a pulse-width-modulation (pwm) dimming interface.

LYTSwitch-6 ICs include both constant-voltage (CV) and constant-current (CC) operation, enabling lighting manufacturers to reduce the number of product variants, resulting in manufacturing and logistics savings.

The new ICs are protected by an advanced thermal foldback system which prevents overheating while delivering as much light as thermally possible in any circumstance or installation.

LYTSwitch-6 ICs feature a built-in 650V or 725V MOSFET and secondary-side FluxLink™ control which eliminates the need for an optocoupler and provides highly accurate output with better than 3% CV and CC over line, load and temperature.

Power conversion for the flyback stage is more than 94% efficient, achieved by using synchronous rectification and quasi-resonant switching which enables high power output without a heatsink. For example, a 35W, 12V, 2.92A design with an additional PFC circuit has been demonstrated to be over 89% efficient.

Devices offer low standby power — less than 15mW in universal ac input conditions - even with line voltage sensing, which allows the IC to protect itself from mains voltage surges and swells.

Comments Hubie Notohamiprodjo, director of product marketing for LED lighting at Power Integrations: "LYTSwitch-6 ICs are ideally suited to smart lighting applications with multiple outputs. By eliminating heatsinks and optocouplers and reducing the size of the output capacitor by as much as 30%, component count and system size are also reduced."

LYTSwitch-6 LED-driver ICs are available now, priced at $0.84 in 10,000 quantities. A reference design (DER-637) describing a 35 W PWM-dimmable LED power supply with efficiency over 89% and a power factor greater than 0.9 is available for download.

DER-637 reference design (click on schematic to enlarge)