描述 Description

The RT8848A is a 8/7/6/5/4/3/2/1 multi-phase synchronous Buck controller which is optimized for high performance graphic microprocessor and support nVidia OVR4i+ spec with PWM-VID interface. The RT8848A adopts AC G-NAVP^TM (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-NAVP^TM topology, the operating frequency of the RT8848A varies with VID, load and input voltage to further enhance the efficiency even in CCM. Besides, for current sensing application, the RT8848A can support either a traditional DCR network current sense from inductor or a smart power stage (SPS) which can directly provide a current monitor signal (IMON).



The RT8848A 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 RT8848A can set internal RAMP amplitude through PINSETx pin and this can optimize stability and load transient performance. The RT8848A also provides complete fault protection functions including over-voltage protection (OVP), under-voltage protection (UVP), channel over-current limit (CH_OC), sum output current protection (SOC) and over-temperature protection (OTP).

特性 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
?RoHS Compliant and Halogen Free

應(yīng)用 Application

? GPU Core Power for OVR4i+ Spec