Linear LED Controllers from Diodes Deliver Efficiency and Accuracy

Diodes announced the AL5814, AL5817, AL5815 and AL5816 linear LED controllers. These devices deliver dimmable and adjustable drive current for LED strings with more than 80% efficiency.

With an input range of 4.5V to 60V, these devices do not require inductors and maintain good EMI performance, making system integration simpler. Internal power dissipation is also minimized compared with other designs due to an external power transistor. The AL58xx series is capable of providing up to 15mA to an external MOSFET or bipolar transistor to drive LED strings. The LED drive current is configured by an external resistor with 4% reference voltage accuracy and excellent temperature stability. In addition, the AL5815 and AL5816 devices support PWM diming, while the AL5814 and AL5817 devices support both analog and PWM dimming.

Protection features include over-temperature and input under-voltage lock-out. The AL5814 and AL5817 devices also provide ‘LED open’ protection via a VFAULT pin, as well as LED thermal fold-back protection. As linear controllers, the AL58xx series exhibits good EMI performance, while the wide operating temperature range of -40°C to +105°C enables the parts to also be used in harsh environments.