Fairchild FAN5343UMPX 6-led series boost led driver with integrated schottky diode and single-wire digital interface Datasheet

FAN5343
6-LED Series Boost LED Driver with Integrated Schottky
Diode and Single-Wire Digital Interface
Features
Description
ƒ
Asynchronous Boost Converter
ƒ
ƒ
ƒ
ƒ
− VOUT up to 24V
Internal Schottky Diode
Up to 500mW Output Power
2.7V to 5.5V Input Voltage Range
Single-Wire Digital Control Interface to Set LED
Brightness Levels
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
− 32 Linear Steps
Fixed Switching Frequency: 1.2MHz
Soft-Start Capability
Input Under-Voltage Lockout (UVLO)
Output Over-Voltage Protection (OVP)
Short-Circuit Detection
Thermal Shutdown Protection (TSD)
Small 6-Lead 2.0 x 2.0 x 0.55mm UMLP Package
The FAN5343 is an asynchronous constant-current LED
driver capable of efficiently delivering up to 500mW to a
string of six (6) LEDs in series. Optimized for small form
factor applications, the 1.2MHz fixed switching frequency
allows the use of small chip inductors and capacitors.
The FAN5343 uses a single-wire digital control interface to
program the brightness levels of the LEDs in 32 linear steps
by applying digital pulses.
For safety, the device features integrated over-voltage, overcurrent, short circuit detection, and thermal shutdown
protection. In addition, input under-voltage lockout protection
is triggered if the battery voltage is too low.
The FAN5343 is available in a very low profile, small form
factor 2mm x 2mm x 0.55mm 6-lead UMLP package that is
green and RoHS compliant.
Applications
ƒ
ƒ
ƒ
ƒ
Cellular Mobile Handsets
Mobile Internet Devices
Portable Media Players
PDA, DSC, MP3 Players
Ordering Information
Part Number
Temperature Range
Package
Packing
FAN5343UMPX
-40 to 85 °C
6-Lead, Ultra-Thin Molded Leadless (UMLP)
Package
Tape and Reel
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wire Digital Interface
August 2010
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Typical Application Diagram
Figure 1. Typical Application
Block Diagram
Figure 2. Block Diagram
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
2
VOUT 1
VIN
2
EN
3
P1
GND
6
GND
5
SW
4
FB
Figure 3. UMLP6 Package (Top View)
Pin Definitions
Pin #
Name
Description
1
VOUT
Boost Output Voltage. Output of the boost regulator. Connect the LEDs to this pin. Connect COUT to GND.
2
VIN
Input Voltage. Connect to power source and decouple with CIN to GND.
3
EN
Enable Brightness Control. Program dimming levels by driving this pin with digital pulses.
4
FB
Voltage Feedback. The boost regulator regulates this pin to 0.25V to control the LED string current. Tie
this pin to a current setting resistor (RSET) between GND and the cathode of the LED string.
5
SW
Switching Node. Tie inductor L1 from the VIN to SW pin.
6
GND
Ground. Tie directly to a GND plane.
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
3
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Pin Configuration
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
Min.
Max.
Units
Voltage on VIN Pin
–0.3
6.0
V
Voltage on FB and EN Pins
–0.3
VIN + 0.3
V
VSW
Voltage on SW Pin
–0.3
25
V
VOUT
Voltage on VOUT Pin
–0.3
25
V
VIN
VFB, VEN
ESD
TJ
TSTG
TL
Parameter
Electrostatic Discharge Protection Level
Human Body Model per
JESD22-A114
3.3
Charged Device Model
per JESD22-C101
2.0
kV
Junction Temperature
–40
Storage Temperature
–65
Lead Soldering Temperature, 10 Seconds
+150
°C
+150
°C
+260
°C
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
VIN
Parameter
Conditions
VIN Supply Voltage
(1)
VOUT
VOUT Voltage
IOUT
VOUT Load Current
500mW Maximum Output Power
Min.
Max.
Units
2.7
5.5
V
6.2
24.0
V
5
25
mA
TA
Ambient Temperature
–40
+85
°C
TJ
Junction Temperature
–40
+125
°C
Note:
1. Application should guarantee that minimum and maximum duty-cycle should fall between 20-85% to meet the specified
range.
Thermal Properties
Junction-to-ambient thermal resistance is a function of application and board layout. This data is measured with four-layer
2s2p boards in accordance to JEDEC standard JESD51. Special attention must be paid not to exceed junction temperature
TJ(max) at a given ambient temperate TA.
Symbol
θJA
Parameter
Junction-to-Ambient Thermal Resistance
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
Typical
Units
70
°C/W
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4
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Absolute Maximum Ratings
VIN = 2.7V to 5.5V and TA = -40°C to +85°C unless otherwise noted. Typical values are at TA = 25°C and VIN = 3.6V.
Symbol
Parameter
Conditions
Min.
Typ.
Max.
Units
0.30
0.75
μA
Power Supplies
ISD
Shutdown Supply Current
EN = GND, VIN = 3.6V
VUVLO
Under-Voltage Lockout Threshold
VUVHYST
Under-Voltage Lockout Hysteresis
VIN Rising
2.10
2.35
2.60
V
VIN Falling
1.90
2.15
2.40
V
250
mV
EN: Enable Pin
VIH
HIGH-Level Input Voltage
VIL
LOW-Level Input Voltage
1.2
200
V
300
0.4
V
400
kΩ
300.0
µs
REN
EN Pull-Down Resistance
tLO
EN Low Time for Dimming
VIN = 3.6V; See Figure 14
0.5
tHI
Time Delay Between Steps
VIN = 3.6V; See Figure 14
0.5
µs
TSD
EN Low, Shutdown Pulse Width
VIN = 3.6V; from Falling Edge of EN
1
ms
Feedback and Reference
VFB
Feedback Voltage
ILED = 20mA from -40°C to +85°C,
2.7V ≤ VIN ≤ 5.5V
IFB
Feedback Input Current
237
250
263
mV
VFB = 250mV
0.1
1.0
μA
VIN = 3.6V, ISW = 100mA
600
VIN = 2.7V, ISW = 100mA
650
SW Node Leakage
EN = 0, VIN = VSW = VOUT = 5.5V,
VLED = 0
0.1
Boost Switch Peak Current Limit
VIN = 3.6V
750
Power Outputs
RDS(ON)_Q1 Boost Switch On-Resistance
ISW(OFF)
ILIM-PK
(2)
mΩ
2.0
μA
mA
Oscillator
fSW
Boost Regulator Switching Frequency
1.0
1.2
22.5
24.5
1.4
MHz
Output and Protection
VOVP
Boost Output Over-Voltage Protection
OVP Hysteresis
V
1.0
VTLSC
VOUT Short Circuit Detection Threshold
VOUT Falling
VIN – 1.4
V
VTHSC
VOUT Short Circuit Detection Threshold
VOUT Rising
VIN – 1.2
V
(3,4)
DMAX
Maximum Boost Duty Cycle
DMIN
Minimum Boost Duty Cycle
85
%
TTSD
Thermal Shutdown
150
°C
THYS
Thermal Shutdown Hysteresis
35
°C
(3,4)
20
%
Notes:
2. SW leakage current includes the leakage current of two internal switches; SW to GND and SW to VOUT.
3. Not tested in production, but guaranteed by design
4. Application should guarantee that minimum and maximum duty cycle fall between 20-85% to meet the specified range.
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
5
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Electrical Specifications
VIN = 3.6V, TA = 25°C, ILED = 25mA, L = 10µH, COUT = 1.0µF
6 LEDs
L = 10µH
COUT = 1.0µF
6 LEDs
L = 10µH
COUT = 1.0µF
ILED = 25mA
Figure 4. 6 LEDs: Efficiency vs. LED Current vs.
Input Voltage
Figure 5. Frequency vs. Input Voltage vs. Temperature
0.8
Delta Feedback Voltage (mV)
5 LEDs
L = 10µH
COUT = 1.0µF
0.6
0.4
0.2
0
-0.2
-40°C
+25°C
-0.4
+85°C
-0.6
2.7
3
3.3
3.6
3.9
4.2
Input Voltage (V)
Figure 6. 5 LEDs: Efficiency vs. LED Current vs.
Input Voltage
Figure 7. Delta of VFB Over Input Voltage and
Temperature for 6 LEDs with L=10µH and COUT=1.0µF
6 LEDs
L = 10µH
COUT = 1.0µF
ILED = 25mA
6 LEDs
L = 10µH
COUT = 1.0µF
ILED = 25mA
Figure 8. Efficiency vs. Input Voltage vs. Temperature
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
Figure 9. Over-Voltage Protection vs. Input Voltage
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FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Typical Characteristics
VIN = 3.6V, TA = 25°C, ILED = 25mA, L = 10µH, COUT = 1.0µF
Figure 10. Line Transient Response for 6 LEDs
Figure 11. Dimming Operation of FAN5343
Figure 12. Startup Waveform for Switch Voltage, Inductor
Current, VFB, and EN for 6 LEDs
Figure 13. Steady-State Waveform for VOUT,
Switch Voltage, and Inductor Current for 6 LEDs
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
7
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Typical Characteristics
Overview
Digital Dimming Control
The FAN5343 is an inductive current-mode boost serial
LED driver that achieves LED current regulation by
maintaining 0.25V across the RSET resistor. The current
through the LED string (ILED) is therefore given by:
The FAN5343 starts driving the LEDs at the maximum
brightness level. After startup, the control logic is ready to
accept programming pulses to decrease the brightness level
by the positive edges applied to the EN pin. Figure 14
illustrates the digital pulse dimming control for the FAN5343.
ILED =
0.25
R SET
(1)
The voltage VOUT is determined by the the sum of the
forward voltages across each LED, plus the voltage
across RSET, which is always 250mV.
Over-Current and Short-Circuit Detection
The boost regulator employs a cycle-by-cycle peak inductor
current limit of ~750mA to protect the switching elements and
the device itself from being damaged.
Over-Voltage / Open-Circuit Protection
UVLO and Soft-Start
If EN has been LOW for more than 1ms, the IC may
initiate a “cold start” soft-start cycle when EN rises,
provided VIN is above the UVLO threshold.
Digital Interface
The FAN5343 implements a single-wire digital interface to
program the LED brightness to one of thirty two (32) levels
spaced in linear steps. With this single-wire solution, the
FAN5343 does not require the system processor to
constantly supply a signal to drive the LEDs.
If the LED string is open circuit, FB remains at 0V and the
output voltage continues to increase in the absence of an
Over-Voltage Protection (OVP) circuit. The FAN5343’s OVP
circuit disables the boost regulator when VOUT exceeds 24.5V
and keeps the regulator off until VOUT drops below 22.5V.
Thermal Shutdown
When the die temperature exceeds 150°C, a reset occurs and
remains in effect until the die cools to 125°C; at which time, the
circuit is allowed to begin the soft-start sequence.
Figure 14. Digital Pulse-Dimming Control Diagram
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
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FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Functional Description
Inductor and Output Capacitor Selection
Table 1.
# of LEDs
5, 6
Recommended External Components
L
10.0µH
Part Number
Manufacturer Min. COUT
LQH43MN100K03
Murata
NLCV32T-100K-PFR
TDK
VLF3010AT-100MR49-1
TDK
1.00µF
Part Number
Manufacturer
UMK212BJ105KG
Taiyo Yuden
Component Placement and PCB Recomendations
Figure 15. Recommended Component Placement
PCB Recommendations
Input Capacitance
In a typical application, the input and output capacitors
should be placed as close to the IC as possible; no
additional capacitance is needed to ensure proper
functionality. However, in a testing environment, where the
FAN5343 is typically powered by a power supply with
relatively long cables, an additional input capacitor (10µF)
may be needed to ensure stable functioning. This
capacitor should be placed close to where the power
supply cables attach to the FAN5343 evaluation board.
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
ƒ The inductor can be connected to VIN with vias through
another layer if needed.
ƒ The feedback pin should be connected back to the IC
on a sub-layer.
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FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Application Information
0.10 C
A
2.0
2X
B
1.45
2.0
PIN1
IDENT
(0.25)
0.10 C
0.80 1.80
2X
6X 0.50
TOP VIEW
6X 0.35
0.55 MAX
0.65
A
0.10 C
RECOMMENDED LAND PATTERN
(0.15)
0.08 C
0.05
0.00
C
SEATING
PLANE
SIDE VIEW
NOTES:
A. PACKAGE CONFORMS TO JEDEC MO-229
EXCEPT WHERE NOTED.
1.35
1.45
PIN1
IDENT
1
3
B. DIMENSIONS ARE IN MILLIMETERS.
6X 0.35
0.25
0.10 C A B
0.05 C
C. DIMENSIONS AND TOLERANCES PER
ASME Y14.5M, 1994.
0.70
0.80
6
D. LANDPATTERN RECOMMENDATION IS BASED
ON FSC DESIGN ONLY.
E. DRAWING FILENAME: MKT-UMLP06Erev2.
4
0.65
0.35
6X 0.25
BOTTOM VIEW
Figure 16. 6-Lead, Ultra-Thin Molded Leadless Package (UMLP)
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without
notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most
recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty
therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
10
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
Physical Dimensions
FAN5343 — 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wired Digital Interface
11
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© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
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