RT6543B

® RT6543A/B High Efficiency Single Synchronous Buck PWM Controller for INTEL VCCIN AUX ICL and TGL General Description The RT6543A/B PWM controller provides high efficiency, excellent transient response, and high DC output accuracy for stepping down high voltage batteries to generate low voltage CPU core, I/O, and chipset RAM. The RT6543A/B supports on chip voltage programming function between 0V and 1.8V by controlling VID1/VID0 inputs. Compared with conventional current-mode PWMs, the RT6543A/B achieves high efficiency without any current sensing resistors. Furthermore, the RT6543A/B has ability to drive synchronous rectifier MOSFETs and enters diode emulation mode at light load condition that also save lots of power consumption. Besides, the RT6543A/B equips with UVLO, OVP, UVP, OTP and current limit protection. All above functions are integrated in a WQFN-20L-3x3 package. Features  A High Efficiency Step-Down DC-DC Controller  Built-in 1% Reference Voltage  2-Bit Programmable Output Voltage with Integrated  Adjustable Switching Frequency  Input Voltage Range : 3V to 24V  Internal Soft-Start to Reduce Inrush Current  Capability of Driving Large Synchronous Rectifier MOSFETs  Power Good Indicator  Cycle-by-Cycle Current Limit  Over-/Under-Voltage Protection  Thermal Shutdown  RT6543A : Slew Down Mode as VID Change  RT6543B : Decay Down Mode as VID Change Pin Configuration (TOP VIEW) VSYS EN VID0 VID1 VCC Applications  Notebook Computers  CPU/GPU Core Sup...