1. Sales Training Presentation
FAN5340: Synchronous Constant-Current Series Boost LED Driver with Integrated Load Disconnect
Sales Training Presentation

2. Introduction
FAN5340 is a synchronous constant-current series boost LED driver with load disconnect that drives 2 to 4 white LEDs
Compact and cost effective solution that provides superior performance
Up to 85% efficiency
Excellent LED Current Linearity
Integrated Load Disconnect
Small form factor: WLCSP-8, 1.57mm x 1.57mm
Driving the LEDs in series provides one excellent benefit – it ensures that all LEDs will have equal brightness

3. FAN5340 Synchronous Constant-Current Series Boost LED Driver
Reduces
Start-up Transients and Audible Interference
Features
Synchronous Operation
Up to 85% Efficiency
500mW Output Power
Drives 2 to 4 40mA
Integrated Disconnect Load
Lower Audible Noise
Saves Power during PWM Dimming
Excellent PWM Linearity
1.2MHz Switching Frequency
Output Over-Voltage Protection
Pkg: WLCSP-8 & 3x3mm MLP
Status
Mobile Handsets
MP3 Players
Mobile Internet Devices
Rugged Handheld PCs
Portable Medical Equipment

4. FAN5340 Key Advantages Integrated Load Disconnect
LED Current Linearity
Equal LED Brightness

5. FAN5340: Load Disconnect FAN5340 integrates true load disconnect
It provides 3 benefits:
Input to output isolation
Prevents leakage current to LEDs from input when FAN5340 is OFF
Reduces audible noise generated by COUT capacitor
Large voltage ripples on this capacitor causes audible noise by mechanical deformation in the ferroelectric compounds

6. FAN5340: LED Current Linearity
FAN5340 dims the LEDs through PWM dimming at 300Hz to 1kHz
To achieve linear LED current especially at low brightness levels, dimming duty cycle is <5% and requires a low PWM frequency i.e. 300Hz
The graph on the left shows LED current linearity over the full range while the one on the right is for dimming duty cycle <2%
Most LED drivers do not provide linear dimming at low LED current levels with a low dimming duty cycle.
At these low light levels, the LED brightness tends to jump down from one level to the next (behave logarithmically) instead of a gradual progression as exhibited by a linear LED current
FAN5340 enables excellent LED current linearity even at very low LED current and dimming duty cycle.

7. 3. Equal LED Brightness
LED Current
20mA
Driving LEDs in series provides equal brightness in each LED
Same amount of current is applied to each LED
No need to worry about LED current matching
FAN5340 drives LEDs in series which enables each LED to have the same brightness level as one another because there is the same amount of current going through each LED
Parallel LED drivers have multiple channels and will need to be matched in order to achieve similar brightness levels but it will not be exactly equal unlike LED driven in series
All LEDs are turned on since sufficient output voltage from FAN5340 is delivered to the LEDs in a string be it 2 to 4 LEDs

8. FAN5340 Objections Cannot Drive 4+ White LEDs Larger Size LED Driver
EMI Noise

9. 1. Unable to Drive 4+ LEDs
FAN5340 is only able to drive up to 4 LEDs in series
However FAN5333 and FAN5336 can drive up to 8 or 9 LEDs in series
Also FAN5343 is available and it will be able to drive up to 6 LEDs
FAN5340 was developed specifically to address backlighting opportunities that needed 2 to 4 LEDs to backlight LCD displays
If the customer has a requirements to drive more LEDs then FAN5333 and FAN5336 are solutions currently available
FAN5343 is also available and have output voltage of 24V so that up to 6 LEDs can be supported

10. 2. Larger LED Driver Size
FAN5340 is in 3x3mm MLP package which is larger than most LED drivers in the market
However these other LED drivers are usually not synchronous or have an integrated load disconnect
If size is an issue than FAN5340 is available in CSP
Dimensions: 1.57 x 1.57mm
As outlined in previous slide, load disconnect provides a number of benefits.

11. 3. EMI Noise
A major concern about using series boost LED drivers is that they radiate EMI
EMI can be minimized by doing the following
Compact part placement
Reduce current loop
Minimize parasitic board capacitance and inductance
Fairchild can provide an optimized PCB layout file for designs
If this is still a concern Fairchild has charge pump LED drivers: FAN5701 and FAN5702 that can be used to backlight LCDs
There are some customers who are reluctant to use series boost LED drivers like the FAN5340 due to EMI concerns
Designers should make the part placement of passive components and FAN5340 as compact as possible
Reduce the current loop to minimize EMI (also a result of compact part placement)
Minimize the size of the switch node which is where the SW pin of FAN5340 is connected to the inductor and do not put a ground plane underneath it

12. FAN5340 + FAN5640 Keypad Lighting LCD Backlight
FAN5340 can be combined with FAN5640 to provide a “turn-key” lighting solution that can support driving LEDs to backlight the LCD display and keypad lighting in a number of applications ranging from portable electronics such as mobile handsets to payment kiosks.
This solution does not require 2 inductors to drive all the LEDs. All that is needed is the one inductor for FAN5340 and the output from it is supplied to FAN5640 which can drive 2 strings of 3 LEDs. The maximum LED current of FAN5640 is determined by the output power of FAN5340 based on its lighting requirements. FAN5340 cannot exceed 500mW and therefore the “system” is constrained to this value. Please see the data sheet for more details.

13. FAN5340 Applications Mobile Handset Space Industrial/Measurement
LCD Modules
Camera Modules
Mobile Internet Devices
Industrial/Measurement
Ruggedized Handhelds
Measurement/Test Equipment
Oscilloscopes
Spectrum Analyzers
Network Analyzers
Payment Kiosks/Systems
PC Products
Ultra-Mobile PCs
PC All-In-One Printers
Portable Consumer
Digital Still Cameras
Video Camcorders
MP3 Players
PMP Players
GPS Handhelds

14. FAN5340 Applications Main Displays in Mobile Handsets
Main Displays in Medical Devices

15. FAN5340 Applications Main Display in Industrial/Embedded Devices
Consumer Electronics

16. Potential FAN5340 Customers
Mobile Handsets
MP3/PMP Players
Cameras & Camcorders
Printers & Fax Machines
Industrial & Measurement
Nokia
Apple
Sony HP
Motorola
Sony/Ericsson
Samsung
Brother
Intermec
JVC
Verifone
iRiver
Olympus
Lexmark
Tektronix
LG Mobile
Creative Labs
Panasonic
Canon
Agilent
Philips
Kodak
Epson
Lecroy
Pantech/Curitel
Microsoft
Casio
OKI
Rhode & Schwarz
Fujitsu
Nextar
Nikon
Anritsu
NEC
SanDisk
Qualcomm
Nintendo
Broadcom
Infineon
ST/EMP

17. Summary
FAN5340 is a high performance synchronous series boost LED driver solution for portable electronics
It provides a number of key benefits to facilitate a better visual experience and electrical performance:
LED current linearity
Lower audible noise and lower power consumption through integrated load disconnect
Small form factor
Can be used in a variety of applications and can be combined with FAN5640 for a “turn-key” lighting solution

18. Pricing & Availability
Fairchild Part Number
Package
Unit 1ku
Availability
FAN5340UCX
WLCSP-8
$0.75
Now
FAN5340MPX
MLP-8
$0.79
August 2010

19. Technical Materials FAN5340 Datasheet
FAN5340 Product Overview
Evaluation Boards
Request via Sales Center
Samples

20. Marketing & Apps Contacts
Marketing Contact
Wayne Seto
Applications Support
Mark Barycza

21. Appendix

22. FAN5333A/B Serial Boost LED Driver w/ Integrated 30V FET Switch
Features
DC-DC Boost Converter w/ Integrated 30V FET Switch
Supports up to 3 Strings of 6 WLEDs (3 x 6)
25V
Feedback Voltage
FAN5633A: 110mV
FAN5633B: 315mV
Up to 1.5A Peak Switch Current
1.6MHz Switching Frequency
Thermal Shutdown
Pkg: SOT23-5
Status
Samples & EVBs: Now
Production: Now

23. FAN5336 Serial Boost LED Driver w/ Integrated 33V FET Switch
Features
DC-DC Boost Converter w/ Integrated 33V FET Switch
Various Output Voltage Configurations:
VOUT = 125mA
VOUT = 75mA
VOUT = 10mA
Able to support up to 3 Strings of 6 WLEDs (3 x 25mA
Up to 1.5A Peak Switch Current
1.5MHz Switching Frequency
Thermal Shutdown
Pkg: 3x3mm MLP6
Status
Samples & EVBs: Now
Production: Now

24. FAN5343 24V Asynch. Series Boost LED Driver w/ Single-Wire
Features
Asynchronous Serial LED Driver w/ Integrated Schottky Diode
Up to 82% efficiency
Supports up to 6 LEDs
Single-wire digital interface
Program 32 different brightness levels
1.2MHz switching frequency
VIN = 2.7V to 5.5V
Over-Voltage Protection
Thermal Shutdown Protection
Pkg: 2.0 x 2.0 x 0.90mm MLP8
Applications
Mobile Handsets
MP3 Players
Mobile Internet Devices

25. FAN5701 180mA, 6-ch. LED Driver with 2 PWM Control Pins
Features
1x/1.5x Charge Pump LED driver
6 LED outputs at 30mA each
Up to 92% efficiency
2 PWM enable pins to control 2 default groups of 4 and 2 LED outputs
Supports PWM dimming up to 20kHz
1.2MHz switching frequency
Pkg: WLCSP-16 & 3x3mm UMLP16
Applications
Mobile Handsets
PMP and MP3 Players
Mobile Internet Devices

26. FAN5702 180mA, 6-ch. LED Driver with I2C Interface
Features
1x/1.5x Charge Pump LED driver
6 LED outputs at 30mA each
Up to 92% efficiency
I2C interface
Configure Group A outputs from 2 to 6 LEDs
Logarithmic dimming with 64 steps for each LED output
Support external PWM dimming up to 20kHz
1.2MHz switching frequency
Pkg: WLCSP-16 & 3x3mm UMLP16
Applications
Mobile Handsets
PMP and MP3 Players
Mobile Internet Devices