RT8859M_14 Datasheet, PDF (1/51 Pages) Richtek Technology Corporation – Multi-Phase PWM Controller for CPU Core Power Supply

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RT8859M
Multi-Phase PWM Controller for CPU Core Power Supply
General Description
The RT8859M is a VR12/IMVP7 compliant CPU power
controller which includes two voltage rails : a 4/3/2/1 phase
synchronous buck controller, the CORE VR, and a single
phase buck controller, the AXG VR. The RT8859M adopts
G-NAVP^TM (Green Native AVP), which is Richtek's
proprietary topology derived from finite DC gain
compensator with current mode control, making it an easy
setting PWM controller, meeting all Intel CPU
requirements of AVP (Active Voltage Positioning). Based
on the G-NAVP^TM topology, the RT8859M also features a
quick response mechanism for optimized AVP performance
during load transient. The RT8859M supports mode
transition function with various operating states. A serial
VID (SVID) interface is built in the RT8859M to
communicate with Intel VR12/IMVP7 compliant CPU. The
RT8859M 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
RT8859M varies with VID, load and input voltage to further
enhance the efficiency even in CCM. The built-in high
accuracy DAC converts the SVID code ranging from 0.25V
to 1.52V with 5mV per step. The RT8859M integrates a
high accuracy ADC for platform setting functions, such as
no-load offset or over-current level. The RT8859M provides
VR ready output signals of both CORE VR and AXG VR.
It also features complete fault protection functions
including over voltage, under voltage, negative voltage, over
current and under voltage lockout. The RT8859M is
available in a WQFN-56L 7x7 small foot print package.
Applications
z VR12 / IMVP7 Intel Core Supply
z Notebook/ Desktop Computer/ Servers Multi-phase CPU
Core Supply
z AVP Step-Down Converter
Features
z 4/3/2/1 + 1 Phase PWM Controller
z G-NAVP^TM Topology
z Serial VID Interface
z 0.5% DAC Accuracy
z Differential Remote Voltage Sensing
z Built-in ADC for Platform Programming
z Accurate Current Balance
z System Thermal Compensated AVP
z Diode Emulation Mode at Light Load Condition for
Multiple and Single Phase
z Fast Transient Response
z VR12 / IMVP7 Compatible Power Management
States
z VR Ready Indicator
z Thermal Throttling
z Current Monitor Output
z Switching Frequency up to 1MHz per Phase
z OVP, UVP, OCP, NVP, UVLO
z Slew Rate Setting/Address Flip Function
z External No-Load Offset Setting for both Rails
z DVID Improvement
z Small 56-Lead WQFN Package
z RoHS Compliant and Halogen Free
Ordering Information
RT8859M
Package Type
QW : WQFN-56L 7x7 (W-Type)
Note :
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
Halogen Free and Pb free)
Richtek products are :
` RoHS compliant and compatible with the current
requirements of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Copyright ©2014 Richtek Technology Corporation. All rights reserved.
DS8859M-07 January 2014
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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