RT8802A Datasheet, PDF (1/28 Pages) Richtek Technology Corporation – 2/3/4/5-Phase PWM Controller for High-Density Power Supply

RT8802A
2/3/4/5-Phase PWM Controller for High-Density Power Supply
General Description
The RT8802A is a 2/3/4/5-phase synchronous buck controller
specifically designed to power Intel^®/ AMD next generation
microprocessors. It implements an internal 8-bit DAC that is
identified by VID code of microprocessor directly. RT8802A
generates VID table that conform to Intel^® VRD10.x and
VRD11 core power with 6.25mV increments and 0.5%
accuracy.
RT8802A adopts innovative time-sharing DCR current sensing
technique to sense phase currents for phase current balance,
load line setting and over current protection. Using a common
GM to sense all phase currents eliminates offset and linearity
variation between GMs in conventional current sensing
methods. As sub-milli-ohm-grade inductors are widely used
in modern motherboards, slight offset and linearity mismatch
will cause considerable current shift between phases. This
technique ensures good current balance in mass production.
Other features include over current protection, programmable
soft start, over voltage protection, and output offset setting.
RT8802A comes to a small footprint package with
VQFN-40L 6x6.
Ordering Information
RT8802A
Package Type
QV : VQFN-40L 6x6 (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.
Features
z 5V Power Supply
z 2/3/4/5-Phase Power Conversion with Automatic
Phase Selection
z 8-bit VID Interface, Supporting Intel VRD11/VRD10.x
and AMD K8, K8_M2 CPUs
z VR_HOT and VR_FAN Indication
z Precision Core Voltage Regulation
z Power Stage Thermal Balance by DCR Current
Sensing
z Adjustable Soft-start
z Over-Voltage Protection
z Adjustable Frequency and Typical at 300kHz per
Phase
z Power Good Indication
z 40-Lead VQFN Package
z RoHS Compliant and 100% Lead (Pb)-Free
Applications
z Intel^®/AMDNew generation microprocessor for Desktop
PC and Motherboard
z Low Output Voltage, High power density DC-DC
Converters
z Voltage Regulator Modules
Pin Configurations
(TOP VIEW)
40 39 38 37 36 35 34 33 32 31
VTT/EN 1
VR_Ready 2
FBRTN 3
FB ⁴
30 PWM5
29 PWM4
28 _PWM3
27 PWM2
COMP 5
SS 6
QRSEL 7
VR_FAN 8
VR_HOT ⁹
TSEN 10
GND
41
26 _PWM1
25 ISP1
24 ISP2
23 ISP3
22 ISP4
21 ISP5
11 12 13 14 15 16 17 18 19 20
VQFN-40L 6x6
DS8802A-04 August 2007
All brandname or trademark belong to their owner respectively
www.richtek.com
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