RT8884C Datasheet, PDF (1/46 Pages) Richtek Technology Corporation – Multi-Phase PWM Controller for CPU Core Power Supply

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RT8884C
Multi-Phase PWM Controller for CPU Core Power Supply
General Description
The RT8884C is a 4/3/2/1 multi-phase synchronous Buck
controller designed to meet Intel VR12.5 compatible CPU
specification with a serial VID control interface. The
RT8884C adopts G-NAVP^TM (Green Native AVP) which is
Richtek's proprietary topology derived from finite DC gain
of EA amplifier with current mode control, making it easy
to set the droop to meet all Intel CPU requirements of
AVP (Adaptive Voltage Positioning). Based on the G-
NAVP^TM topology, the RT8884C also features a quick
response mechanism for optimized AVP performance
during load transient. The RT8884C supports mode
transition function with various operating states. A Serial
VID (SVID) interface is built in the RT8884C to
communicate with Intel VR12.5 compliant CPU. The
RT8884C supports VID on-the-fly function with three
different slew rates : Fast, Slow and Decay. By utilizing
the G-NAVP^TM topology, the operating frequency of the
RT8884C varies with VID, load current and input voltage
to further enhance the efficiency even in CCM. Besides
G-NAVP^TM, the CCRCOT (Constant Current Ripple
Constant On Time) technology provides superior output
voltage ripple over the entire input/output range.
Features
 Intel VR12.5 Serial VID Interface Compatible
 4/3/2/1 Phase PWM Controller
 G-NAVP^TM Topology
 0.5% DAC Accuracy
 Differential Remote Voltage Sensing
 Built-in ADC for Platform Programming
 Accurate Current Balance
 System Thermal Compensated AVP
 Diode Emulation Mode at Light Load Condition for
Single Phase Operation
 Fast Transient Response
 VR Ready Indicator
 Thermal Throttling
 Current Monitor Output
 OVP, UVP, OCP, NVP, UVLO
 External No-Load Offset Setting
 DVID Enhancement
 Small 32-Lead WQFN Package
 RoHS Compliant and Halogen Free
Applications
 VR12.5 Intel Core Power Supply
 Notebook/Desktop Computer/Servers Multi-phase CPU
Core Power Supply
 AVP Step-Down Converter
Simplified Application Circuit
To PCH
To CPU
RT8884C
VR_RDY ^PWM1
VR_HOT
VCLK
VDIO
ALERT
PWM2
PWM3
PWM4
RT9624A
RT9624A
RT9624A
RT9624A
V_CORE
Copyright ©2015 Richtek Technology Corporation. All rights reserved.
DS8884C-00 July 2015
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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