Fairchild FAN5610 service manual

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FAN5610

LED Driver for White, Blue or any Color LED

Features

• LED Driver for 4 Parallel-connected LEDs

• Low Voltage Drop (<350mV) to Support Direct Li-ion
Applications with Low V

• Independent Control Loop for Each LED

• Regulated, Matched Constant Current in LEDs

• No External Components

• No EMI, No Switching Noise

• Built-in DAC for Digital and PWM Brightness Control

• Up to 91% Maximum Efficiency

• Up to 84mA (21mA/LED) Bias Current

• 2.7V to 5.5V Input Voltage Range

•I

< 1µA in Shutdown Mode

CC

• 3mmX3mm MLP-8 Package

LEDs

F

Applications

• Cell Phones

• Handheld Computers

• PDA, DSC, MP3 Players

• LCD Display Modules

• Keyboard Backlight

• LED Displays

Description

The FAN5610 generates matched current source drives for a
maximum of four LEDs. Since each LED current source has
its own self-regulating loop, precise current matching is
maintained even if there is a substantial forward voltage
spread among the LEDs. LED pre-selection therefore is not
required. In order to minimize voltage drop, and maximize
efficiency, the value of the internal current sense resistors
connected in series with the LEDs is very low (10 Ω ). This is
an important consideration for direct DC-driven white LEDs
in battery-powered systems.

The LEDs’ current can be set to 0mA (OFF Mode), 7mA,
14mA, and 21mA with a built-in two-bit digital-to-analog
converter. Customized current settings can also be used.
When the control bits are set to zero, the internal circuitry is
disabled and the quiescent current drops below 1µA.

Both digital input lines (A, B) can be pulse-width-modulated
(PWM).
be obtained within the 1 to 20 mA range. The FAN5610 is
available in an 8-lead 3X3 MLP package.

Using PWM, any value of average LED current can

Typical Application

D
A
C

V

IN

V

IN A

IN

D1D2D3D4

FAN5610

IN B

GND

REV. 1.0.2 10/28/03

FAN5610 PRODUCT SPECIFICATION

Pin Assignment

Pin Descriptions

Pin Name Pin Function Description

D1 Cathode of Diode No.1

D2 Cathode of Diode No. 2

IN B DAC Input B, Active High

IN A DAC Input A, Active High

V

IN

D3 Cathode of Diode No. 3

D4 Cathode of Diode No. 4

GND Ground

Input Voltage

D1

D2

FAN5610

IN B

IN A

3x3mm 8-LEAD MLP PACKAGE

GND

D4

D3

V

IN

2

REV. 1.0.2 10/28/03

2

21 26

PRODUCT SPECIFICATION FAN5610

Absolute Maximum Ratings

Parameter Min. Max. Unit

V

,

IN A/IN B Voltage to GND -0.3 6.0 V

IN

Lead Soldering Temperature (10 seconds) 300 °C

Operating Junction Temperature Range 150 °C

Storage Temperature -55 150 °C

Electrostatic Discharge Protection Level (Note1) HBM 4 kV

CDM 2

Recommended Operating Conditions

Parameter Min. Typ. Max. Unit

Input Voltage Range, V

(Note2) 2.7 5.5 V

IN

Operating Ambient Temperature Range -40 25 85 °C

DC Electrical Characteristics

(V

=3.3V to 5.5V, T

IN

operating temperature range.)

= 25 °C, unless otherwise noted. Boldface values indicate specifications over the ambient

A

Parameter Conditions Min. Typ. Max. Units

Supply Current, OFF Mode IN A = 0

<1

µA

IN B = 0

Output Current Accuracy V

> 0.3V

D

14.8

mA

IN A = 1, IN B = 1

LED to LED Current Matching V

= 3.6V

IN

-7.5 7.5

%

IN A = 1, IN B = 1

DAC Input Voltage Threshold LOW

HIGH

Peak Efficiency LED V

Notes:

1. Using Mil Std. 883E, method 3015.7(Human Body Model) and EIA/JESD22C101-A (Charge Device Model).

2. The minimum operating voltage depends on the LED’s operating voltage, as shown in the "Application Information" section.

=3V at 20mA 91 %

F

0 0.3 × V

0.6 × V

IN

IN

V

IN

V

REV. 1.0.2 10/28/03

3