Off-line LED drivers optimised for European lighting markets

November 20, 2013 // By Graham Prophet
Power Integrations has added parts to its LYTSwitch™-4 LED-driver IC family, with parts optimised for high-line applications (High-line, i.e. for an input voltage range of 185 VAC to 265 VAC as opposed to the the low-line input voltage range of 90 VAC to 132 VAC.) The parts deliver accurate output current and high efficiency for bulb and tube applications and high-bay lighting; lamps deliver uniform light output and provide exceptional performance in TRIAC-dimmable applications.

LYTSwitch-4 ICs feature a combined PFC and CC single-stage converter topology resulting in a power factor greater than 0.95 and efficiencies of over 90% in typical applications. Designs based on the new drivers easily meet EN61000-3-2C regulations for total harmonic distortion (THD); optimised designs deliver less than 10% THD. Regulation is better than ±5% across load and production spread, reducing the need for over-design to meet minimum luminance targets, cutting system cost. The devices’ high switching frequency (132 kHz) enables smaller, lower-cost magnetics to be used, and frequency dithering reduces EMI filtering requirements. These factors enable LED-driver designs to fit easily into space-restricted bulb styles.

Power Integrations ads that, used with leading-edge and trailing-edge TRIAC dimmers, and at low conduction angles, designs comply with NEMA SSL-7. Start-up is very fast, typically less than 500 msec, even when dimmed to less than 10% light output, and “pop-on” is virtually eliminated.

You can evaluate the LYTSwitch-4 LED-driver IC family using a new high-line LED lighting reference design that has been co-developed with Cree. DER-396 describes a PAR38 spotlight LED driver design. These documents and all other similar reference designs with Cree are hosted at

High-line LYTSwitch-4 ICs come in eSIP-7C (E) and eSIP-7F (L) packages, priced from $0.58 (non-dimming) to $0.62 (dimming) (10,000). Reference designs are downloadable at

Power Integrations;