Oct 24-06 Rev L

SP633 Synchronous Buck Controller

© 2006 Sipex Corporation

FEATURES

■

5V to 24V Input step down converter

■

Up to 30A output capability

■

Highly integrated design, minimal components

■

■

Overcurrent circuit protection with auto-restart

■

Power Good Output, ENABLE Input

■

Maximum Controllable Duty Cycle Ratio up to 92%

■

Wide BW amp allows Type II or III compensation

■

Programmable Soft Start

■

Fast Transient Response

■

HighEfficiency:Greaterthan95%possible

■

Available in Lead Free, RoHS Compliant

6-Pin QFN package

■

External Driver Enable/Disable

■

U.S. Patent #6,922,04

The SP633 is a synchronous step-down switching regulator controller optimized for high

efficiency.Thepartisdesignedtobeespeciallyattractiveforsinglesupplystepdowncon-

version from 5V to 24V. The SP633 is designed to drive a pair of external NFETs using a

fixed300kHzfrequency,PWMvoltagemodearchitecture.ProtectionfeaturesincludeUVLO,

thermal shutdown, output short circuit protection, and overcurrent protection with auto restart.

The device also features a PWRGD output and an enable input. The SP633 is available in

a space saving 6-pin QFN and offers excellent thermal performance.

TYPICAL APPLICATION CIRCUIT

DESCRIPTION

ISN

SP6133

16 Pin QFN

3mm x 3mm

8

7

6

5

4

3

2

1

GH

GL

PGND

12

11

10

9

16

15

14

13

GND

ISP

SWN

NC

CBST

0.1uF

R1

68.1K, 1%

RZ3

1K

R2

21.5K, 1%

MT, Si4394DY

9.75 mOhm, 30V

CZ3

560pF

CP1

39 pF

RZ2

23.2K

CZ2

1500pF

CF1

22pF

10-15V

CSP

6.8nF

VIN

GND

GND

VOUT

POWERGOOD

VCC

VFB

COMP

SS

PGND

GND

PWRGD

ISN

EN

ISP

CSS

47nF

GL

SWN

UVIN

BST

GH

3.3V

0-10A

VIN

DBST

BAT54WS

CVCC

10uF

C5

0.1uF

R3 10K

SP6133

C2

22uF

CS

0.1uF

RS2

5.11K

RS1

5.11K

SC5018-2R7M

2.7uH, 15A, 4.1mOhm

C3

100uF

ENABLE

C1

22uF

C4

100uF

MB, Si4320DY

4 mOhm, 30V

Note: Die attach paddle is internally connected to GND.

SP6133

Synchronous Buck Controller

Solved by

TM