FAN5343 [FAIRCHILD]
6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wire Digital Interface; 6 - LED系列升压型LED驱动器,集成肖特基二极管和单线数字接口型号: | FAN5343 |
厂家: | FAIRCHILD SEMICONDUCTOR |
描述: | 6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wire Digital Interface |
文件: | 总11页 (文件大小:1314K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
August 2010
FAN5343
6-LED Series Boost LED Driver with Integrated Schottky
Diode and Single-Wire Digital Interface
Features
Description
Asynchronous Boost Converter
VOUT up to 24V
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.
−
Internal Schottky Diode
Up to 500mW Output Power
2.7V to 5.5V Input Voltage Range
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.
Single-Wire Digital Control Interface to Set LED
Brightness Levels
−
32 Linear Steps
For safety, the device features integrated over-voltage, over-
current, short circuit detection, and thermal shutdown
protection. In addition, input under-voltage lockout protection
is triggered if the battery voltage is too low.
Fixed Switching Frequency: 1.2MHz
Soft-Start Capability
Input Under-Voltage Lockout (UVLO)
Output Over-Voltage Protection (OVP)
Short-Circuit Detection
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.
Thermal Shutdown Protection (TSD)
Small 6-Lead 2.0 x 2.0 x 0.55mm UMLP Package
Applications
Cellular Mobile Handsets
Mobile Internet Devices
Portable Media Players
PDA, DSC, MP3 Players
Ordering Information
Part Number
Temperature Range
Package
Packing
6-Lead, Ultra-Thin Molded Leadless (UMLP)
Package
FAN5343UMPX
-40 to 85 °C
Tape and Reel
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
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
Pin Configuration
VOUT 1
6 GND
P1
GND
2
3
5
VIN
EN
SW
FB
4
Figure 3. UMLP6 Package (Top View)
Pin Definitions
Pin # Name
Description
Boost Output Voltage. Output of the boost regulator. Connect the LEDs to this pin. Connect COUT to GND.
Input Voltage. Connect to power source and decouple with CIN to GND.
1
2
3
VOUT
VIN
Enable Brightness Control. Program dimming levels by driving this pin with digital pulses.
EN
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.
4
FB
Switching Node. Tie inductor L1 from the VIN to SW pin.
Ground. Tie directly to a GND plane.
5
6
SW
GND
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
3
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
Parameter
Min.
Max.
Units
VIN
Voltage on VIN Pin
–0.3
–0.3
–0.3
–0.3
6.0
VIN + 0.3
25
V
V
V
V
VFB, VEN Voltage on FB and EN Pins
VSW
Voltage on SW Pin
VOUT
Voltage on VOUT Pin
25
Human Body Model per
JESD22-A114
3.3
2.0
ESD
Electrostatic Discharge Protection Level
kV
Charged Device Model
per JESD22-C101
TJ
TSTG
TL
Junction Temperature
–40
–65
+150
+150
+260
°C
°C
°C
Storage Temperature
Lead Soldering Temperature, 10 Seconds
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
Parameter
VIN Supply Voltage
VOUT Voltage(1)
Conditions
Min.
Max.
Units
VIN
VOUT
IOUT
2.7
6.2
5
5.5
24.0
25
V
V
VOUT Load Current
Ambient Temperature
Junction Temperature
500mW Maximum Output Power
mA
°C
°C
TA
–40
–40
+85
+125
TJ
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
Parameter
Typical
Units
Junction-to-Ambient Thermal Resistance
70
°C/W
θJA
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
4
Electrical Specifications
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
Power Supplies
ISD
Shutdown Supply Current
EN = GND, VIN = 3.6V
0.30
2.35
2.15
250
0.75
2.60
2.40
μA
V
VIN Rising
2.10
1.90
VUVLO
Under-Voltage Lockout Threshold
VIN Falling
V
VUVHYST Under-Voltage Lockout Hysteresis
mV
EN: Enable Pin
VIH
VIL
REN
tLO
HIGH-Level Input Voltage
LOW-Level Input Voltage
EN Pull-Down Resistance
EN Low Time for Dimming
Time Delay Between Steps
EN Low, Shutdown Pulse Width
1.2
V
V
0.4
400
200
0.5
0.5
1
300
kΩ
µs
µs
ms
VIN = 3.6V; See Figure 14
300.0
tHI
VIN = 3.6V; See Figure 14
TSD
VIN = 3.6V; from Falling Edge of EN
Feedback and Reference
ILED = 20mA from -40°C to +85°C,
2.7V ≤ VIN ≤ 5.5V
VFB
Feedback Voltage
237
250
0.1
263
1.0
mV
IFB
Feedback Input Current
VFB = 250mV
μA
Power Outputs
V
IN = 3.6V, ISW = 100mA
600
650
RDS(ON)_Q1 Boost Switch On-Resistance
mΩ
VIN = 2.7V, ISW = 100mA
EN = 0, VIN = VSW = VOUT = 5.5V,
VLED = 0
ISW(OFF) SW Node Leakage(2)
0.1
2.0
1.4
μA
ILIM-PK
Oscillator
fSW
Boost Switch Peak Current Limit
VIN = 3.6V
750
mA
Boost Regulator Switching Frequency
1.0
1.2
MHz
Output and Protection
Boost Output Over-Voltage Protection
OVP Hysteresis
22.5
24.5
1.0
VOVP
V
VTLSC
VTHSC
DMAX
VOUT Short Circuit Detection Threshold VOUT Falling
VOUT Short Circuit Detection Threshold VOUT Rising
Maximum Boost Duty Cycle(3,4)
VIN – 1.4
VIN – 1.2
V
V
85
%
%
°C
°C
DMIN
Minimum Boost Duty Cycle(3,4)
20
TTSD
Thermal Shutdown
150
35
THYS
Thermal Shutdown Hysteresis
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
Typical Characteristics
VIN = 3.6V, TA = 25°C, ILED = 25mA, L = 10µH, COUT = 1.0µF
6 LEDs
6 LEDs
L = 10µH
L = 10µH
C
OUT = 1.0µF
C
OUT = 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
0.6
0.4
0.2
0
5 LEDs
L = 10µH
COUT = 1.0µF
-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
C
OUT = 1.0µF
ILED = 25mA
6 LEDs
L = 10µH
COUT = 1.0µF
ILED = 25mA
Figure 8. Efficiency vs. Input Voltage vs. Temperature
Figure 9. Over-Voltage Protection vs. Input Voltage
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
6
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
Functional Description
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.
0.25
ILED
=
(1)
RSET
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.
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-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.
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.
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.
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
8
Application Information
Inductor and Output Capacitor Selection
Table 1. Recommended External Components
# of LEDs
L
Part Number
LQH43MN100K03
Manufacturer Min. COUT
Part Number
Manufacturer
Murata
5, 6
10.0µH
NLCV32T-100K-PFR
VLF3010AT-100MR49-1
TDK
TDK
1.00µF
UMK212BJ105KG
Taiyo Yuden
Component Placement and PCB Recomendations
Figure 15. Recommended Component Placement
Input Capacitance
PCB Recommendations
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.
The inductor can be connected to VIN with vias through
another layer if needed.
The feedback pin should be connected back to the IC
on a sub-layer.
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
9
Physical Dimensions
0.10 C
A
2.0
2X
B
1.45
2.0
(0.25)
PIN1
IDENT
0.10 C
0.80 1.80
2X
0.50
6X
TOP VIEW
0.65
0.35
6X
0.55 MAX
A
0.10 C
0.08 C
RECOMMENDED LAND PATTERN
(0.15)
C
0.05
0.00
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.
C. DIMENSIONS AND TOLERANCES PER
ASME Y14.5M, 1994.
0.70
0.80
0.35
0.25
D. LANDPATTERN RECOMMENDATION IS BASED
ON FSC DESIGN ONLY.
6X
0.10 C A B
0.05 C
E. DRAWING FILENAME: MKT-UMLP06Erev2.
4
6
0.65
0.35
0.25
6X
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
© 2009 Fairchild Semiconductor Corporation
FAN5343 • Rev. 1.0.4
www.fairchildsemi.com
11
相关型号:
FAN5343UMPX
6-LED Series Boost LED Driver with Integrated Schottky Diode and Single-Wire Digital Interface
FAIRCHILD
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