High Efficiency, Constant Current

12 Watt Boost White-LED Driver

•Operating Voltage:2.4V~6.5V

•High Operating Frequency: 1.5MHz

•High Output Voltage: Up to 34V(max)

•Shutdown Current <1 A

•16V Output Over-voltage protection (min)

•Digital Dimming Control.

•Built-in Cycle-by Cycle Current-limiting.

•Built-in Soft-Start Function.

•0.2V Low Reference Voltage(3%)

•Tiny SOT23-6 Package

• LED Module

• LED Backlight for LCD Display(7 ~21 )

• Constant Current Source

The KB4313 step-up converter drives white LEDs

with a constant current to provide backlight in cell

phones, PDAs, and other hand-held devices. It

features allowing series connection of the white

LEDs so that the LED currents are identical for

uniform brightness. An enable input can be pulsed

repeatedly to adjust LED’s brightness. The fast 1.5

MHz current-mode PWM control allows for smaller

capacitor and inductor. Fault condition protection

uses

cycle-by-cycle

current

limiting

to

sense

maximum inductor current, thermal protection and

over-voltage protection. Also included soft-start

eliminates inrush current during start-up. The 0.2V

low reference voltage minimized the power loss

across the current-setting resistor.

The KB4313 is available in SOT23-6 packages

LX

VREF(200mV)

+

-

FB

ON/OFF

Control

Logic / PWM

Dimming

Control

GND

Control Logic

EN

VREF

0.2V

N

VBG

1.23V

VIN

+

-

VBG

OVP

+

-

Overvoltage

Protection

Current Limit

1.4A

CTL

CTL

16V-20V(6.5uA)

Soft-Start

1

KB4313

Kingbor Technology Co.,Ltd

TEL:(86)0755-26508846 FAX:(86)0755-26509052

•High Efficiency: Up to 95%

•High Output Power: Up to 12W(Vin=12V)

APPLICATIONS

FEATURES

DESCRIPTION

SIMPLIFIED BLOC DIAGRAM

• USB host

”

”

REV: 2.0