RT9241 Datasheet, PDF (1/13 Pages) List of Unclassifed Manufacturers – Two-Phase DC/DC Controller for CPU Core Power Supply

Preliminary
RT9241
Two-Phase DC/DC Controller for CPU Core Power Supply
General Description
The RT9241 is a two-phase buck DC/DC controller
integrated with all control functions for high
performance processor VRM. The RT9241 drives 2
buck switching stages operating in 180 degree
phase shift. The two-phase architecture provides
high output current while maintaining low power
dissipation on power devices and low stress on
input and output capacitors. The high equivalent
operating frequency also reduces the component
dimension and the output voltage ripple in load
transient.
RT9241 regulates both easily set voltage and
current loops. Precise current sharing for power
stage is achieved by differential input current sense
and processing circuit. The settings of current
sense, droop tuning 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 RT9241 uses a 5-bit DAC of 1.1V to 1.85V
(25mV/step) output with load current droop
compensation to meet the strict VRM transient
requirement. The IC monitors the VCORE voltage
for PGOOD and 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.
Ordering Information
RT9241… …
Package Type
S : SOP-20
Operating temperature range
C: Commercial standard
Features
z Two-Phase Power Conversion
z VRM 9.0 DAC Output with Active Droop
Compensation for Fast Load Transient
z Precise Channel Current Sharing with
Differential Sense Input
z Hiccup Mode Over Current Protection
z Programmable Under Voltage Lockout and
Soft Start
z High Ripple Frequency, (Channel Frequency
200KHz) Times Channel Number
Applications
z Power Supply for Server and Workstation
z Power Supply for High Current Microprocessor
Pin Configurations
Part Number
Pin Configurations
RT9241CS
(Plastic SOP-20)
TOP VIEW
VID4 ¹
VID3 2
VID2 ³
VID1 ⁴
VID0 ⁵
COMP ⁶
FB ⁷
ADJ ⁸
DVD ⁹
SS ¹⁰
20 _VDD
19 PGOOD
18 ISP1
17 PWM1
16 PWM2
15 ISP2
14 _VSEN
13 _GND
12 _ISN1
11 _ISN2
DS9241-00 November 2001
www.richtek-ic.com.tw
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