Si9139

Vishay Siliconix

New Product

Document Number: 71841

S-22317—Rev. A, 16-Dec-02

www.vishay.com

1

Multi-Output, Individual On/Off Control Power-Supply Controller

FEATURES

D Five Output 50-W, Triple Output DC-DC-Controller

D Up to 95% Efficiency

D "3% Total Regulation (Line, Load and Temperature)

D 4.5-V to 30-V Input Voltage Range

D Two Fixed 1.5-V, 1.8-V, 2.0-V, 2.2-V, 2.5-V, 2.8-V, 3.3-V Outputs

D One Adjustable 1.24-V to 20-V Output

D 3.3-V Reference Output

D 5-V/30-mA Linear Regulator Output

D Individual ON/OFF Control for A and B Outputs

D 300-kHz Low-Noise Fixed Frequency Operation

D High Efficiency Pulse Skipping Mode Operation at Light Load

D Only Three Inductors RequiredNo Transformer

D Internal Under Voltage Lockout and Soft-Start

D Minimum Number of External Control Components

D 28-Pin SSOP Package

D Output Overvoltage Protection

D Output Undervoltage Shutdown

D Power-Good Output (RESET)

APPLICATIONS

D Notebook and Subnotebook Computers

D PDAs and Mobile Communicators

D Portable Display

D Multimedia Set-Top Box

D Telecommunications Infrastructure

D Network Equipment

D Distributed Power Conversion

DESCRIPTION

The Si9139 is current-mode PWM and PSM converter

controller, with two high current, high efficiency synchronous

buck controllers and an adjustable buck-boost controller

whose output can be set between 1.24 V and 20 V with an

external resistor divider. Designed for fixed and portable

devices, it offers a total of five power outputs (three tightly

regulated dc/dc converter outputs, a precision 3.3-V reference

and a 5-V LDO output. Individually controlled power-up

sequencing, power-good signal with delay, internal frequency

compensation

networks

and

automatic

boot-strapping

simplify the system by minimizing the number of external

components

while

achieving

conversion

efficiencies

approaching 95%.

The Si9139 is available in a 28-pin SSOP package and

specified to operate over the extended commercial (-40

_C to

85

_C) temperature range.

FUNCTIONAL BLOCK DIAGRAM

5-V

Linear

Regulator

3.3-V

Voltage

Reference

1.5- V - 3.3-V

1.8- V - 3.3-V

Auxiliary SMPS

Programmable

(4.5 V to 30 V)

0 - 6 A

(5.0 V)

(+3.3 V)

1.24-V to 20-V/500 mA

Adjustable

Power_Good

RESET

(Power_Good)

Logic Control

0 - 6 A

C

B

A