RT8801 Datasheet, PDF (1/23 Pages) Richtek Technology Corporation – Multi-Phase PWM Controller for CPU Core Power Supply with Serial Programming Interface

Preliminary
RT8801
Multi-Phase PWM Controller for CPU Core Power Supply
with Serial Programming Interface
General Description
Features
The RT8801 is a multi-phase synchronous buck controller
which is implemented with full control functions for Intel^®
VR10.0/10.1-compliant CPU. The RT8801 could be
operated with 2, 3 or 4 buck switching stages operating
in interleaved phase set automatically. The multiphase
architecture provides high output current while maintaining
low power dissipation on power devices and low stress
on input and output capacitors.
RT8801 is one of RichTek CPU core power solutions which
integrates a specific series programming interface for the
controller operation configuration. There are several
registers implemented for the specific parameters
configuration including VID for core power, and signal for
load current indication. User can program the configuration
of the parameters easily via the specific programming
interface. With the implementation of RT8801, the part
provides more flexibility and feature for customers advanced
segment product design.
The RT8801 applies the DCR sensing technology newly
as well; with such a topology, the RT8801 extracts the
DCR of output inductor as sense component to deliver a
more precise load line regulation and better thermal
balance for next generation processor application. For
current sense setting, droop tuning, V_CORE initial offset
and over current protection are independent to
compensation circuit of voltage loop. The feature greatly
facilitates the flexibility of CPU power supply design and
tuning. The DAC output of RT8801 supports VRD10.x with
6-bit VID input, precise initial value & smooth V_CORE
transient at VID jump. The IC monitors the V_CORE voltage
for over-voltage protection. Soft-start, over-current
protection and programmable under-voltage lockout are
also provided to assure the safety of microprocessor and
power system. The RT8801 comes to the package of
VQFN-32L 5x5.
z Multi-Phase Power Conversion with Automatic
Phase Selection
z 6-bits VRD10.x DAC Output with Active Droop
Compensation for Fast Load Transient
z Smooth V_CORE Transition at VID Jump
z Power Stage Thermal Balance by DCR Current
Sense
z Hiccup Mode Over-Current Protection
z Adjustable Switching Frequency (50kHz to 400kHz
per Phase)
z Under-Voltage Lockout and Soft-Start
z High Ripple Frequency Times Channel Number
z 2-wires programming interface
z Software Programmable VID
z 32-Lead VQFN Package
z RoHS Compliant and 100% Lead (Pb)-Free
Applications
z Intel^® VR10.x-compliant Processors Voltage Regulator
z Low Output Voltage, High power density DC-DC
Converters
z Voltage Regulator Modules
Ordering Information
RT8801
Package Type
QV : VQFN-32L 5x5 (V-Type)
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Note :
Richtek Pb-free and Green products are :
`RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
`Suitable for use in SnPb or Pb-free soldering processes.
`100% matte tin (Sn) plating.
DS8801-04 August 2007
All brandname or trademark belong to their owner respectively
www.richtek.com
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