IW2202 Datasheet | iWatt Corporation

.Data Sheet.co.kr i W2202 Digital SMPS Controller Preliminary Data 1 Application Blue-Angel-pliant PFC-controlled switch-mode power supplies up to 150 watts. 4 Description The i W2202 is a digital switching mode power supply controller for PFC applications. Its is typically used with the PFC-corrected BIFRED (Boost Integrated with Flyback Rectifier/Energy storage DC/DC) topology, shown in Figure 1. The BIFRED topology is a singlestage, single-switch topology that bines a boost converter with an isolated flyback converter, achieving power-factor correction with a low parts count. An i W2202-based power supply looks like a resistor to the AC line. Unlike attempts to control the BIFRED topology with analog controllers, the all-digital i W2202 provides a near-unity power factor without placing high voltage stresses on the bulk capacitor. The i W2202 uses a proprietary new digital control technology called pulse Train™ to achieve efficiencies in excess of 85% across a wide load range, and across the universal input range of 85-270VAC, 50-60 Hz. Internally, the i W2202 uses real-time waveform analysis to determine crucial circuit parameters. The reflected secondary voltage of the flyback transformer is sensed at precisely calculated times to determine the secondary voltage, the transformer reset time, and the ideal zero-voltage switching point Measurements are performed during the OFF time of every cycle, and the results determine what is done on the next cycle. The dynamic response time of the circuit is less than half a cycle. Boost Inductor Auxiliary Winding 85-270 V, 50-60 Hz Output AC Input 2 Features - - - - - - - - - - Pulse Train™ regulation allows voltage, current and PFC to be controlled independently Primary-only feedback eliminates optoisolators and simplifies design No loop pensation ponents required ±1% regulation over a 100:1 load variation Built-in soft-start Adaptive pulse Train regulation keeps the bulk capacitor voltage below 400V Operates...