RT9227A Datasheet, PDF (1/10 Pages) Richtek Technology Corporation – Advanced PWM and Dual Fixed Linear Power Controller

Preliminary
RT9227A
Advanced PWM and Dual Fixed Linear Power Controller
General Description
The RT9227A 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 RT9227A 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 a fixed 2.5V ±2.5% output
voltage. The linear controller drives an external N-
channel MOSFET or a low cost NPN bipolar
transistor to provide a fixed 1.5V ±2.5%.
The RT9227A 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
RT9227A… …
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 HIP6016
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 Fixed 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 Distributed Power Supplies
Pin Configurations
Part Number
Pin Configurations
RT9227ACS
(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
DS9227A-02 July 2001
www.richtek-ic.com.tw
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