RT9228 Datasheet, PDF (1/10 Pages) Richtek Technology Corporation – ADVANCED PWM AND DUAL LINEAR POWER CONTROLLER

RT9228
Advanced PWM and Dual Linear Power Controller
General Description
The RT9228 is a 3-in-one power controller optimized
for high-performance microprocessor and computer
applications. The IC integrates a synchronous buck
PWM controller, a linear regulator, and a linear
controller as well as monitoring and protection
functions into a 24-pin SOP package. The PWM
controller regulates the microprocessor core voltage.
The linear regulator provides power for the clock
driver circuit and the linear controller regulates power
for the GTL bus.
The RT9228 features an Intel-compatible, TTL 5-bit
programmable DAC that adjusts the core voltage
from 2.1V to 3.5V in 0.1V increments and from 1.3V
to 2.05V in 0.05V steps. The 5-bit DAC has a typical
±1% tolerance. The linear regulator uses an internal
drive device to provide 2.5V ±2.5% output voltage.
The linear controller drives an external N-channel
MOSFET or a low cost NPN bipolar transistor to
provide 1.5V ±2.5%.
The RT9228 monitors all the output voltages. A
Power-good signal is issued when the core voltage is
within ±10% of the DAC setting and the other levels
are above their under-voltage levels. Additional build-
in over-voltage protection for the core output uses
the lower MOSFET to prevent output voltage above
115% of the DAC setting. The PWM over-current
function monitors the output current using the voltage
drop across the upper MOSFET’s R_DS(ON), which
eliminates the need for a current sensing resistor.
Ordering Information
RT9228… …
Package type
S : SOP-24
Operating temperature range
C: Commercial standard
Features
z 3-in-one Regulated Voltages for Microprocessor
Core, Clock, and GTL
z Compatible with HIP6018B
z Power-good Output Voltage Monitor
Switching section
z 5-bit DAC Programmable from 1.3V to 3.5V
z ±1% DAC Accuracy
z Fast Transient Response
z Full 0% to 100% Duty Cycle Driver
z Fixed 200kHz Switching Frequency
z Adaptive Non-overlapping Gate Driver
z Over-current Monitor Uses MOSFET R_DS(ON)
z Over-voltage Protection Uses Lower MOSFET
Linear Section
z User-adjustable Linear Regulator Output Voltage
z MOSFET or NPN Driving Capability
z Ultra Fast Response Speed
z Under-voltage Protection
z Internal Thermal Shutdown
Applications
z Full Motherboard Power Regulation for Computer
z Low-voltage Distribution Power Supplies
Pin Configurations
Part Number
Pin Configurations
RT9228CS
(Plastic SOP-24)
VCC 1
VID4 2
VID3 3
VID2 4
VID1 ⁵
VID0 ⁶
PGOOD ⁷
FAULT ⁸
SS ⁹
NC ¹⁰
FB2 ¹¹
VIN2 12
TOP VIEW
24 UGATE1
23 ^PHASE1
22 LGATE1
21 PGND
20 OCSET1
19 _VSEN1
18 _FB1
17 _NC
16 _FB3
15 _GATE3
14 _GND
13 VOT2
DS9228-03 July 2001
www.richtek.com
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