General Description

The RT8848C is a 8/7/6/5/4/3/2/1 multi-phase

synchronous Buck controller which is optimized for

high-performance graphic microprocessor and

supports nVidia OVR4i+ spec with PWM-VID interface.

The RT8848C 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 RT8848C varies with

VID, load and input voltage to further enhance the

efficiency even in CCM. Besides, for current sensing

application, the RT8848C can support either a

traditional DCR network current sensing from inductor

or a smart power stage (SPS) which can directly

provide a current monitor signal (IMON).

The RT8848C 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 RT8848C can set internal

RAMP amplitude through PINSETx pin and this can

optimize stability and load transient performance. The

RT8848C also provides complete fault protection

functions including overvoltage protection (OVP),

undervoltage protection (UVP), channel overcurrent

limit (CH_OC), sum output current protection (SOC)

and over-temperature protection (OTP). The

recommended junction temperature is −40C to 125C.

Features

⚫ Multi-Phase PWM Controller

⚫ PWM-VID Dynamic Voltage Control

⚫ Support 1.8V PWM-VID Interface

⚫ Power State Indicator

 LPC (Low Phase Count), PSI = Low

 APS (Auto Phase Shedding), PSI = Mid

 HPC (High Phase Count), PSI = High

⚫ External Reference Input Control

⚫ 8/7/6/5/4/3/2/1 Phase Hardware Setting

⚫ Adjustable Soft-Start Time

⚫ Adjustable Switching Frequency

⚫ Adjustable Phase Current Balance

⚫ Support Standby Mode

⚫ UVP/OVP/OTP/SOC/CH_OC/TSEN Protection

⚫ Adjustable Protection Thresholds

⚫ Power Good Indicator

⚫ ADC Reporting for IMON, TSEN and VSEN

⚫ Support I2C Interface for Programming

Applications

⚫ GPU Core Power for OVR4i+ Spec