A driver IC for dimmable LEDs

A circuit diagram shows an SSL2103 chip using external power from an external MOS transistor in a flyback application for varying the brightness of an LED.
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It makes no sense to put super-efficient LEDs on ordinary dimmers. The dimmer would consume more energy than the LEDs being dimmed. That's why NXP Semiconductors, a company headquartered in The Netherlands (www.nxp.com), developed the SSL22103 IC. The chip uses on-time-mode and frequency controls to adjust the brightness of higher power LED lights (PAR2, PAR30, and PAR38). It works with most dimmers (Triac and transistor), thanks to two external current sinks or bleeder transistors. A strong bleeder is used for zero-cross dimmer resets and Triac latching while a weak bleeder maintains the hold current through the dimmer. It will also work with non-dimmable LEDs. The chip comes in a small, SO14 package and can be supplied in buck, flyback, and non-isolated configurations. An internal VCC generator supports start-up from rectified mains voltage (100, 110, 02 230 V), and the chip meets safety and power-factor regulations. It has built-in overcurrent and short-winding protection, as well as demagnetization detection. At nominal operating temperatures, the chip should perform for more than 75,000 hr.

Say hello to the NXP engineers who helped design and build the SSL2103 chip.
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