CL8800 Sequential Linear LED Driver Features Description Minimal component count (base config: CL8800 + CL8800 is designed to drive a long string of inexpen- 6 resistors + diode bridge) sive, low-current LEDs directly from the AC mains. A No magnetics, no capacitors basic driver circuit consists of CL8800, six resistors, Up to 7.5W output (13W w/ heat sink) and a bridge rectifier. Two to four additional compo- nents are optional for various levels of transient protec- >110Lm/W using efficient LEDs tion. No capacitors, EMI filters, or power factor 85% typical electrical efficiency correction circuits are needed. >0.95 power factor <20% THD line current A string of series/parallel LEDs is tapped at six loca- Low conducted EMI w/o filters tions. Six linear current regulators sink current at each tap and are sequentially turned on and off. Thereby 85% LED luminous utilization tracking the input sine wave voltage. Voltage across Phase dimmer compatible with an RC network each regulator is minimized when conducting, provid- ing high efficiency. Output current at each tap is individ- Applications ually resistor-adjustable. Cross-regulation, as the CL8800 switches from one regulator to another, pro- Fluorescent tube retrofit vides smooth transitions. The current waveform can be Incandescent & CFL bulb replacement tailored to optimize for input voltage range, line/load General LED lighting regulation, output power/current, efficiency, power fac- tor, THD, dimmer compatibility, and LED utilization. With the addition of an RC network, the driver is com- patible with phase dimming. 2015 Microchip Technology Inc. DS20005357A-page 1CL8800 Package Type 33 1 GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND GND See Table 2-1 for pin information Typical Application Circuit Transient Protection AC Mains TAP1 TAP2 TAP3 TAP4 TAP5 TAP6 BIAS CL8800 GND 100 - 120VAC additional SET1 SET2 SET3 SET4 SET5 SET6 components for 230VAC DS20005357A-page 2 2015 Microchip Technology Inc. SET1 NC BIAS SET2 NC TAP1 SET3 NC TAP2 SET4 TAP3 NC TAP4 SET5 TAP5 SET6 TAP6