© 2006 Semtech Corp.

POWER MANAGEMENT

SC614

United States Patent No. 6,504,422

www.semtech.com

16

Application Examples

Main Backlight Plus Flash

D1

LED

C2

1u

434mA Max (500ms)

D2

LED

D3

LED

D4

LED

D5

LED

32mA Max

32mA Max

32mA Max

32mA Max

306mA Max.

C1

2u2

C3 1u

C4 1u

VIN

11

VIN

17

EN

2

SDA

7

SCL

8

ASEL

5

SDIM

3

MDIM

4

FL

6

VOUT

9

VOUT

16

M1

1

M2

24

M3

23

M4

22

S1/FL3

20

S2/FL2

19

S3/FL1

18

GND

12

GND

21

U1

SC614

EN

SDA

SCL

SDIM

FL

MDIM

328mA Max Continuous

VBAT

R1

Pull-up

R2

Pull-up

VLOGIC

Note: R1 and R2

pull-up resistors are a

requirement of the I2C

specification

MAIN BACKLIGHT

FLASH

Features:

•

Up to 4 LED main backlight with up to 32mA per LED

•

PWM dimming of backlight using MDIM pin

•

Up to 306mA flash capability controlled by FL pin

Register Settings (20mA backlight currents and 300mA flash current used as an example):

0x00: set to 0x7F to enable all 7 current sinks for use

0x01 through 0x04: set to 0x32 for 20mA per current sink

0x05 through 0x07: set to 0xFA for 100mA per current sink, 300mA total

0x08: set to 0x46 for Flash Mode enabled, 250kHz charge pump frequency, FL pin controls S1/FL3, S2/FL2

and S3/FL1