RT8241

® RT8241 High Efficiency Single Synchronous Buck PWM Controller General Description The RT8241 PWM controller provides high efficiency, excellent transient response, and high DC output accuracy needed for stepping down high voltage batteries to generate low voltage CPU core, I/O, and chipset RAM supplies in notebook computers. The RT8241 supports on chip voltage programming function between 0.675V and 0.9V by controlling GX digital inputs. The constant-on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns “instant-on” response to load transients while maintaining a relatively constant switching frequency. The RT8241 achieves high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by its ability to drive very large synchronous rectifier MOSFETs and enter diode emulation mode at light load condition. The buck conversion allows this device to directly step down high voltage batteries at the highest possible efficiency. The RT8241 is intended for CPU core, chipset, DRAM, or other low voltage supplies as low as 0.675V. The RT8241 is available in a WQFN-12L 2x2 package. Ordering Information RT8241 Package Type QW : WQFN-12L 2x2 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) Z : ECO (Ecological Element with Halogen Free and Pb free) Switching Frequency Operation A : 300kHz B : 400kHz C : 500kHz Note : Richtek products are : ` RoHS...