FAN5608_06 FAIRCHILD [Fairchild Semiconductor], FAN5608_06 Datasheet

FAN5608_06

Manufacturer Part Number

FAN5608_06

Description

Serial / Parallel LED Driver with Current-Regulated, Step-Up DC/DC Converter

Manufacturer

FAIRCHILD [Fairchild Semiconductor]

Datasheet

1.FAN5608_06.pdf (13 pages)

Current page: 1 of 13
Download datasheet (366Kb)

FAN5608 Rev. 1.0.5 • 8/8/06

FAN5608 Serial / Parallel LED Driver with

Current-Regulated, Step-Up DC/DC Converter

Features

Applications

Ordering Information

Two independent channels drive up to six LEDs

per channel

Adaptive output voltage drive to maximize efficiency

PFM mode of operation of the boost circuit

Up to 85% efficiency

Up to 2×20mA output

Two built-in DACs for independent (digital) brightness

control for both channels

LED current can be duty-cycle-modulated, 0 to 20mA

Digital, analog, and PWM brightness control

2.7V to 5.5V input voltage range

500KHz operating frequency

Soft-start feature

Low shutdown current: I

Open-load protection

Minimal external components needed

Space-saving 4x4mm 12-lead MLP packages

Cell phones

Handheld computers

PDAs, DSCs, MP3 players

Keyboard backlights

LED displays

FAN5608DHMPX

Part Number

< 1μA

Pb-Free

Yes

Schottky Diode

Internal

Description

The FAN5608 is an integrated Schottky diode LED

driver, which generates regulated output currents from a

battery input voltage of 2.7V to 5V. An internal MOS

switch and the external inductor deliver the necessary

voltage

compensation loop continuously monitors the lowest

LED cathode voltage of both channels and adjusts the

is determined by the highest LED forward voltage of the

selected channel. This adaptive nature allows the

FAN5608 architecture to deliver high efficiency. Up to

twelve LEDs can be connected in series as long as the

summed forward voltage does not exceed the maximum

specification of 24V. It is not required to match an equal

number of LEDs serially within each channel; FAN5608

delivers the highest efficiency and best current

regulation in the balanced configuration.

FAN5608 has two internal two-bit D/A converters that

provide independent programmability to each output

channel. In analog programming, "B" pins must be GND

(logic “0”); a resistor must be connected between pin “A”

and a fixed supply voltage. The output current can be

programmed to any desired value within the specified

range. The FAN5608DHMPX is available in a 4x4mm

12-lead MLP package. A single external resistor sets the

current and turns the device ON and OFF.

OUT

voltage to the minimum value. The minimum V

MLP-12 4x4mm

Package

the

load.

The

Packing Method

Tape and Reel

proprietary

www.fairchildsemi.com

August 2006

internal

OUT

Related parts for FAN5608_06

FAN5608_06 Summary of contents

Page 1

FAN5608 Serial / Parallel LED Driver with Current-Regulated, Step-Up DC/DC Converter Features Two independent channels drive up to six LEDs per channel Adaptive output voltage drive to maximize efficiency PFM mode of operation of the boost circuit Up to 85% ...

Page 2

Page 3

Pin Definitions Pin # Name Description 1 GND Ground 2 CH1 First LED Cathode 3 B1 DAC DAC A1 5 VIN Input Voltage 6 A2 DAC DAC B2 8 CH2 Second LED Cathode 9 ...

Page 4

Typical Application Digital Brightness Control C IN 2.7V to 5.5V DAC Input For CH1 DAC Input For CH2 Analog Brightness Control 4.7µH 2.7V to 5.5V V EXTERNAL © 2006 Fairchild Semiconductor Corporation FAN5608 Rev. 1.0.5 • ...

Page 5

Electrical Specifications Recommended operating conditions and component values are per the Figure 18 test circuit. Typical values are at 25°C and V =3.6V. Boldface indicates specifications over ambient operating temperature (-40°C to +85°C). IN Parameter Supply current in OFF mode ...

Page 6

Digital Static Control The FAN5608’s digital decoder allows selection of the following modes of operation: OFF, 5mA, 10mA, and 20mA per channel OFF 5mA LED Analog Static Control In Analog Mode, B1 and ...

Page 7

PWM Control Figure PWM controlled LOW Input B Input (PWM) Duty Cycle I LED 0mA Figure HIGH and B is PWM controlled Input (PWM) B Input (PWM) I ...

Page 8

Typical Characteristics T =25C 3.6V, unless otherwise specified. A BAT Figure 11. Peak power efficiency Startup Response V =3.6V, L=6.8uH Tim e 200µS/Div Figure 13. Startup Response Design and Component Selection Guidelines Inductor Selection The inductor ...

Page 9

FET. Using L = 3.3μΗ and increasing the load to 12 LED x 20mA (P = 800mW) requires V OUT maintain a constant 20mA current through LEDs. An inductance L ...

Page 10

FAN5608 Efficiency Curves L = 6.9µH 2.7V to 5.5V INDB DAC Input for CH1 FAN5608DHMPX A2 B1 DAC Input for CH2 B2 Figure 16. FAN5608 with four LEDs L = 6.8µH 2.7V to 5.5V INDB V IN ...

Page 11

L = 3.3µH 2.7V to 5.5V INDB DAC Input for CH1 FAN5608DHMPX A2 B1 DAC Input for CH2 B2 Figure 22. FAN5608 with ten LEDs L = 2.7µH 2.7V to 5.5V INDB DAC Input ...

Page 12

Dimensional Outline Drawings Dimensions are in millimeters unless otherwise noted. © 2006 Fairchild Semiconductor Corporation FAN5608 Rev. 1.0.5 • 8/8/06 Figure 26. 4x4mm 12-Lead MLP 12 www.fairchildsemi.com ...

Page 13

TRADEMARKS The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is not intended exhaustive list of all such trademarks. ACEx™ GlobalOptoisolator™ ActiveArray™ GTO™ Bottomless™ HiSeC™ 2 Build it Now™ I ...

Related keywords

FAN5608_06 datasheet
FAN5608_06 data sheet
FAN5608_06 pdf datasheet
FAN5608_06 component
FAN5608_06 part
FAN5608_06 distributor
FAN5608_06 RoHS
FAN5608_06 datasheet download