RT8845A

® RT8845A Multi-Phase PWM Controller with PWM-VID Reference General Description The RT8845A is a 4/3/2/1 phase synchronous Buck PWM controller which is optimized for high performance graphic microprocessor and computer applications. The RT8845A adopts G-NAVPTM (Green Native AVP) which is Richtek's proprietary topology derived from finite DC gain of EA amplifier with current mode control. By utilizing the GNAVPTM topology, the operating frequency of the RT8845A varies with VID, load and input voltage to further enhance the efficiency even in CCM. Moreover, the G-NAVPTM with CCRCOT (Constant Current Ripple COT) technology provides superior output voltage ripple over the entire input/ output range. The RT8845A provides complete fault protection functions including Over-Voltage (OV), Negative Voltage (NV), Over-Current (OC) and Under-Voltage Lockout (UVLO). The RT8845A is available in the WQFN40L 5x5 package. The RT8845A features external reference input and PWMVID dynamic output voltage control, in which the feedback voltage is regulated and tracks external input reference voltage. Other features include adjustable switching frequency, dynamic phase number control, internal/external soft- start, power good indicator, and enable functions. Features  Multi-Phase PWM Controller  Power State Indicator  1P-CCM/4P-CCM/1P-DEM  Support 1.8V PWM-VID Interface  External Reference Input Control  PWM-VID Dynamic Voltage Control  Dynamic Phase Number Control  Internal/External Sof...