The RT8843B is a 3/2/1 multi-phase synchronous Buck controller which is optimized for high performance graphic microprocessor and support nVidia OVR3i+ spec with PWM-VID interface. It can support both DrMOS with current output and DCR current sensing. The RT8843B adopts AC G-NAVPTM (Green Native AVP) which is Richtek's proprietary topology derived from finite DC gain of internal GM amplifier with current mode control. By utilizing the AC G-NAVPTM topology, the operating frequency of the RT8843B varies with VID, load and input voltage to further enhance the efficiency even in CCM. Moreover, the AC G-NAVPTM with CCRCOT (Constant Current Ripple COT) technology provides superior output voltage ripple over the entire input/output range.
The RT8843B features external reference input and PWM-VID dynamic output voltage control, in which the output voltage is regulated and tracks external input reference voltage. The RT8843B can set internal RAMP amplitude through PINSETx pin and this can optimize stability and load transient performance. The RT8843B also provides complete fault protection functions including Over-Voltage Protection (OVP), Under-Voltage Protection (UVP), Over-Current Limit (OCL) and Over-Temperature Protection (OTP).
Applications
- GPU Core Power for OVR3i+ Spec