The RT8880B is a 3 + 2 phases PWM controller, and is compliant with AMD SVI2 Voltage Regulator Specification to support both CPU core (VDD) and Northbridge portion of the CPU (VDDNB). The RT8880B features CCRCOT (Constant Current Ripple Constant On-Time) with G-NAVP (Green-Native AVP), which is Richtek's proprietary topology. The G-NAVP makes it an easy setting controller to meet all AMD AVP (Adaptive Voltage Positioning) VDD/VDDNB requirements. The droop is easily programmed by setting the DC gain of the error amplifier. With proper compensation, the load transient response can achieve optimized AVP performance. The controller also uses the interface to issue VOTF Complete and to send digitally encoded voltage and current values for the VDD and VDDNB domains. It can operate in single phase and diode emulation mode and reach up to 90% efficiency in different modes according to different loading conditions. The RT8880B provides special purpose offset capabilities by pin setting. The RT8880B also provides power good indication, over-current indication (OCP_L) and dual OCP mechanism for AMD SVI2 CPU core and NB. It also features complete fault protection functions including over-voltage, under-voltage and negative-voltage protections.
Applications
- AMD SVI2 Mobile CPU
- Laptop Computer