FAN5610 — LED Driver for White, Blue, or Any Color LED
March 2008
FAN5610
LED Driver for White, Blue, or Any Color LED
Features
LED Driver for Four Parallel-connected LEDs
Low Voltage Drop (<350mV) to Support Direct
Li-ion Applications with Low V
F
LEDs
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
CC
< 1µA in Shutdown Mode
3mm x 3mm MLP-8 Package
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. To minimize voltage
drop and maximize efficiency, the value of the internal
current sense resistors connected in series with the
LEDs is very low (10Ω). This is an important
consideration for direct DC-driven white LEDs in
battery-powered systems.
The LED 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). Using PWM, any value of average
LED current can be obtained within the 1 to 20 mA
range. The FAN5610 is available in an 8-lead 3x3mm
MLP package.
Applications
Cell Phones
Handheld Computers
PDA, DSC, MP3 Players
LCD Display Modules
Keyboard Backlight
LED Displays
Typical Application
Ordering Information
Part Number
FAN5610MPX
Operating Temperature Range
-40 to +85°C
Package
3x3mm, 8-Lead, Molded
Leadless Package (MLP)
Packing Method
Tape and Reel
All packages are lead free per JEDEC: J-STD-020B standard.
© 2003 Fairchild Semiconductor Corporation
FAN5610 • Rev. 1.0.3
www.fairchildsemi.com
FAN5610 — LED Driver for White, Blue, or Any Color LED
Pin Configuration
Figure 1. Pin Configuration
Pin Definitions
Pin Name
D1
D2
IN B
IN A
V
IN
D3
D4
GND
Description
Cathode of Diode No.1
Cathode of Diode No. 2
DAC Input B, Active High
DAC Input A, Active High
Input Voltage
Cathode of Diode No. 3
Cathode of Diode No. 4
Ground
© 2003 Fairchild Semiconductor Corporation
FAN5610 • Rev. 1.0.3
www.fairchildsemi.com
2
FAN5610 — LED Driver for White, Blue, or Any Color LED
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device
reliability. The absolute maximum ratings are stress ratings only.
Symbol
V
IN
T
L
T
JA
T
STG
ESD
Parameter
IN A / IN B Voltage to GND
Lead Soldering Temperature, 10 Seconds
Operating Junction Temperature Range
Storage Temperature
Human Body Model, JESD22-A114
Charged Device Model, JESD22-C101
Min.
-0.3
Max.
6.0
+300
+150
Unit
V
°C
°C
°C
kV
-55
4
2
+150
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to Absolute Maximum Ratings.
Symbol
V
IN
(1)
Parameter
Input Voltage Range
Operating Ambient Temperature Range
Min.
2.7
-40
Typ.
+25
Max.
5.5
+85
Unit
V
°C
T
A
Note:
1. The minimum operating voltage depends on the LED operating voltage, as described in the
Application
Information
section.
DC Electrical Characteristics
V
IN
= 3.3V to 5.5V, T
A
= 25°C, unless otherwise noted.
Boldface
values indicate specifications over the ambient
operating temperature range.
Symbol
I
IN
I
OUT
I
MATCH
V
IN_DAC
Parameter
Supply Current, OFF Mode
Output Current Accuracy
LED to LED Current Matching
DAC Input Voltage Threshold
Peak Efficiency
Conditions
IN A = 0, IN B = 0
V
D
> 0.3V, IN A = 1, IN B = 1
V
IN
= 3.6V, IN A = 1, IN B = 1
LOW
HIGH
LED V
F
= 3V at 20mA
Min.
Typ.
<1
Max.
2
26.0
7.5
0.3 × V
IN
V
IN
Units
µA
mA
%
V
%
14.8
-7.5
0
0.6 × V
IN
21.0
91
© 2003 Fairchild Semiconductor Corporation
FAN5610 • Rev. 1.0.3
www.fairchildsemi.com
3
FAN5610 — LED Driver for White, Blue, or Any Color LED
Block Diagram
V
IN
D1
D2
D3
+
Error Amp.
+
Error Amp.
-
-
10
Bandgap
Reference
2-bit
DAC
10
+
Error Amp.
+
Error Amp.
D4
-
IN A
10
-
10
IN B
GND
Figure 2. Block Diagram
© 2003 Fairchild Semiconductor Corporation
FAN5610 • Rev. 1.0.3
www.fairchildsemi.com
4
FAN5610 — LED Driver for White, Blue, or Any Color LED
Typical Performance Characteristics
Unless otherwise specified, T
A
= 25°C and using Fairchild QTLP670IW Super Bright LED.
Figure 3. LED Current vs. Input Voltage
(Low V
F
– White LED)
Figure 4. LED Current vs. Cathode Voltage
Figure 5. LED Current vs. Temperature
Figure 6. Line Transient Response
Figure 7. DAC Transient Response
© 2003 Fairchild Semiconductor Corporation
FAN5610 • Rev. 1.0.3
www.fairchildsemi.com
5