APPLICATION NOTE
R01AN0674EJ0100 Rev.1.00 Page 1 of 33
2011.05.31
78K0/Ix2 Microcontrollers
78K0/Ix2 Microcontrollers
LED Lighting System with PFC Control
Readers The target readers of this document are us er engineers who design an d develop LED li ghting systems and
power supply systems.
The target products are as follows:
•78K0/IB2:
μ
PD78F0745, 78F0746, 78F0755, 78F0756
•78K0/IA2:
μ
PD78F0743, 78F0744, 78F0753, 78F0754
•78K0/IY2:
μ
PD78F0740, 78F0741, 78F0742, 78F0750, 78F0751, 78F0752
Purpose The purpose of this document is to describe the features and the control methods for the LED lighting
system with PFC control using the 78K0/Ix2 microcontroller.
Caution The sample programs are for reference only. We do not guarantee their operation. Before using the
sample programs, evaluate them thoroughly on the user's s et.
CONTENTS
CHAPTER 1 OVERVIEW....................................................................................................................2
1.1 Introduction................................................................................................................................2
1.2 Features of LED Lighting System Control with 78K0/Ix2...........................................................3
1.3 System Block Diagram ..............................................................................................................4
1.4 Pin Functions of 78K0/Ix2..........................................................................................................5
1.5 System Operation Overview......................................................................................................6
CHAPTER 2 CONTROL METHODS FOR VARIOUS FUNCTIONS...................................................7
2.1 LED Control...............................................................................................................................7
2.1.1 LED control overview ..........................................................................................................7
2.1.2 LED control software design ...............................................................................................9
2.1.3 Calculating coefficients of PI control formula ......................................................................13
2.2 PFC Control...............................................................................................................................16
2.2.1 PFC control overview..........................................................................................................16
2.2.2 PFC control software design...............................................................................................19
APPENDIX A EZ-0011 EXTERNAL APPEARANCE .........................................................................25
APPENDIX B EZ-0011 CIRCUIT DIAGRAM......................................................................................26
APPENDIX C EZ-0011 PARTS LIST .................................................................................................27
R01AN0674EJ0100
Rev.1.00
2011.05.31