Studies On Driving Technology Of Low Loss Switching Power Supply For Flexible Electroluminescent Panel

The inorganic electroluminescent panel is a thin and light surface light source,which has the characteristics of uniform light emission,long service life and wide operating tempera ture range.Besides,the electroluminescent panel has a mature preparation process,low preparation cost,and ca n be produced in large quantities.They do not cause environmental pollution during use and disposal.It has been widel y used in road traffic warnings,advertising,wearable electronic devices,and Garden decoration and other fields.Therefore,it is a characteristic development direction of the lighting field.Aiming at solving the problems existing in the current driving technology of electroluminescent panel,this thesis performs the research in three aspects: driving power supply technology,delay condu ction circuit,and music spectrum design.The specific research work and innovation points are as follows:1.A half-bridge switching power suppl y circuit is adopted as the driving circuit scheme of the electroluminescent panel.Since the electroluminescen t panel has the structure similar to a flat capacitor,an AC high voltage drive is required.Therefore,this paper mainl y uses a half-bridge switching power suppl y circuit with a simple topology and suitable power output as the primary drive circuit and th en cooperates with the control circuit design to form a complete drive power solution design.2.A delay conduction circuit of low-loss driver for electroluminescent(EL)panel is designed.Since the electroluminescent panel behaves as a capacitive load,the transient current through the transistors of the EL panel charging/discharging during the switching period of the transistors in the switching driver circuit can be very large,large switching loss and high equilibrium temperature as well as burning dow n of the transistors in the driver's switching circuit will be caused.Therefore,a delayed conducting circuit is connected in the output circuit of the driver,so that the output current passes after the transistor is full y turned on to a low resistance s tate.The switching loss of the transistor is decreased,and the reliabilit y is improved.3.The application scheme of the C-tune music score is proposed.Since the material of the electroluminescent panel is a piezoelectric material,there is a reverse piezoelectric effect,that is,a "howling" phenomenon occurs when it is subjected to a specific alternating voltage.Therefore,the driving pulse frequency is set to the rate of different notes.As the music changes,the harsh noise is converted into pleasan t musical sound.At the same time,the PWM voltage regulating circuit is used to follow the driving frequency to control the power suppl y voltage of the switching circuit,thereb y making the electroluminescent panel drive at different rates,and can keep the brightness unchanged without flickering.