Design And Research Of Linear Constant Current LED Drive Chip For Filament Lamp

With governments supporting the energy industry greatly, the IC industry developing itself gradually and the circuit designer’ skill getting mature constantly, the energy-saving products are going into the market progressively. With the emergence of energy-saving lamps, the requirements of the drive power are much higher. People expect to get the cheaper product used steadily, reliably and efficiently. Therefore, studying a kind of driving power for energy-saving lamps with good performance and cost-effective has been become a hot topic in recent years.Considering that the traditional linear constant current drive power has the poor adaptability and the low linear regulation, in this thesis, we design a linear constant current LED driver chips with better adjustment. The output voltage of the chip can be adjusted by detecting the fluctuation of the load voltage, so that the chip has better adaptability of the load with matching the load voltage. Also, the output voltage of the chip can be adjusted by detecting the fluctuation of the power grid voltage, so that the chip has better linear adjustment of the load with matching the input voltage. In this thesis, we have proposed a kind of linear constant current drive circuit with adaptive and have verified the accuracy of circuit architecture with MATLAB. Finally we have designed the modules in the chip by using CADENCE and have simulated.The chip designed in this thesis has been taped out successfully. The test of the chip has been done. It shows that the output voltage of the chip ranges from 160 V to 270 V, the line regulation is ± 0.5%, the efficiency is much more than 75%, and the power factor is much more than 0.3. It also shows that the chip has no performance of flicker and pressure flash, has the characteristic of the surge voltage up to 1000 V, and has the lumens utilization of the lamp up to 100% during application. Compared to traditional linear constant current chip, this kind of adaptive linear constant current driver chip spreads out an expansive prospects in application.