
LED driver delivers fast start-up with no pop-on, no dead travel
LYTSwitch ICs combine PFC and CC into a single switching stage, increasing driver efficiency to more than 90% in typical applications, delivering a power factor greater than 0.95 and easily meeting EN61000-3-2C requirements for total harmonic distortion (THD). Optimized designs deliver less than 10% THD. The combined single-stage converter topology also eliminates high-voltage electrolytic bulk capacitors, leading to greatly extended driver lifetimes even in high ambient temperatures. Accurate primary-side control yields true tight CC performance with better than +/- 5 percent regulation across load, a wide temperature range and production variation enabling tighter design margins and reduced system cost. High switching frequency of 132 kHz means that small, low-cost magnetics can be used in space-constrained bulb applications, while frequency jittering ensures reduced EMI filter requirements. LYTSwitch devices also offer all the usual safety features common to Power Integrations products, including overvoltage, overcurrent and over-temperature protection.
The LYTSwitch family of LED-driver ICs enables better dimming performance when used with leading-edge and trailing-edge TRIAC dimmers even at low conduction angles, complying with NEMA SSL6. Start-up is very fast, typically less than 500 ms, even when dimmed to less than 10% output. Bulbs using LYTSwitch ICs will turn on at almost the same dimming angle as it was at turn-off, virtually eliminating pop-on. Dead band in TRIAC dimming is also eliminated as the LYTSwitch controller ensures that dimming occurs as soon as the dimmer is operated.
Reference designs, including a PAR-38 lamp design developed in partnership with Cree, are downloadable at https://www.powerint.com/en/design-support/reference-designs/design-examples.
The product datasheet and product introduction videos are also available on the Power Integrations website at https://www.powerint.com/products/lytswitch-family/lytswitch.
