基于OB2532的原边反馈LED驱动电路设计

Design of the primary-side feedback LED driver circuit based on OB2532

文中应用高性能离线式PWM控制器OB2532,设计了一款小功率LED驱动电路,电路采用原边反馈方式。与传统的副边反馈相比,原边反馈驱动电路省去了光耦和TL431芯片,降低了成本,提高了系统的可靠性。所设计的LED驱动电路具有恒压恒流控制特性。实测的结果来表明:4个1 W的白光LED正常工作,亮度非常高,测试参数达到设计要求。

In this paper, a small power LED driving circuit is designed based on high performance off-line PWM controller OB2532. The driving circuit has a primary-side feedback characteristics. Compared with the traditional feedback mode compared, the optical coupling and TLA31 chip are left out in the primary-side feedback driver circuit. The cost of driving circuit is reduced, and the reliability of the system is improved. The LED drive circuit has constant voltage/current control characteristics. Experimental results show： four 1W white light LED can normally work, and has very high brightness. Test parameters meet the design requirements.