FAN5608 Fairchild Semiconductor, FAN5608 Datasheet

no-image

FAN5608

Manufacturer Part Number
FAN5608
Description
Serial/Parallel LED Driver with Current-Regulated/ Step-Up DC/DC Converter
Manufacturer
Fairchild Semiconductor
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
FAN5608DHMPX
Manufacturer:
FAIRCHILD/仙童
Quantity:
20 000
Company:
Part Number:
FAN5608DHMPX
Quantity:
1 700
Features
• Two Independent Channels Drive up to Six LEDs per
• Adaptive Output Voltage Drive to Maximize Efficiency
• PWM/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
• LED’s Current Can be Duty-Cycle-Modulated between
• Digital, Analog, and PWM Brightness Control
• 2.7V to 5V Input Voltage Range
• 0.5MHz Operating Frequency (8MHz internal clock)
• Soft Start
• Low Shutdown Current: I
• LED Short Circuit Protection
• Minimal External Components Needed
• Available in space saving 8-lead and 12-lead MLP
Applications
• Cell Phones
• Handheld Computers
• PDAs, DSCs, MP3 Players
• Keyboard Backlights
• LED Displays
FAN5608
Serial/Parallel LED Driver with Current-Regulated,
Step-Up DC/DC Converter
Typical Application
DAC Input For CH1
DAC Input For CH2
2.7V to 5V
Channel
Control for Both Channels
0 to 20mA
Packages.
C
IN
L = 4.7µH
4X4mm MLP-12 Package
with internal Schottky diode
Order Code: FAN5608DHMPX
B2
IND
V
A1
B1
A2
IN
CC
< 1
GND
V
IND
CH2
CH1
NC
OUT
NN
µ
A
4.7µF
Digital Brightness Control
V
OUT
2.7V to 5V
DAC Input For CH1
DAC Input For CH2
Description
The FAN5608 LED driver generates regulated output cur-
rents from a battery with input voltage varying between 2.7V
to 5V. An internal NMOS switch drives an external inductor,
and a Schottky diode delivers the inductor’s stored energy to
the load. Proprietary internal circuitry continuously monitors
the currrent on both strings and automatically adjusts the
generated output DC voltage to the lowest minimum value
required by the LEDs string with the highest summarized
forward voltage. This adaptive nature of the FAN5608
ensures operation at the highest possible efficiency. Soft start
circuitry prevents excessive current drawn from the supply
during power on. Any number of LEDs can be connected in
series as long as the summed forward voltages do not exceed
the specified operating output voltage range. Although it is
not required to have an equal number of LEDs connected in
series within each branch, the highest efficiency and best
current regulation is always achieved when an equal number
of LEDs are serially connected.
In the FAN5608 device, two internal two-bit D/A converters
provide independent programmability of each output channel
current. Analog programming of the output current is
also possible in the FAN5608. To do this, ground the "B"
pins and connect a resistor between the "A" pins and a
fixed supply voltage. The output current can then be
programmed to any desired value within its specified range.
The FAN5608DMPX/FAN5608MPX version uses a single
C
IN
L = 4.7µH
4X4mm MLP-12 Package
with external Schottky diode
Order Code: FAN5608HMPX
B2
IND
V
A1
B1
A2
IN
www.fairchildsemi.com
GND
CH2
CH1
IND
NC
NC
4.7µF
REV. 1.0.3 6/28/04
V
OUT

Related parts for FAN5608

Related keywords