This was one of my first designs when I started designing power LED circuits. The DC/DC controller is ON-Semi NCP3065. It requires power inductor, schottky diode and some other passives. NCP3065 is PWM controller suitable for many topologies, including buck, boost or sepic. Circuit presented here is classical step down buck (click to enlarge):
Archive for the ‘Power LED’ Category.
I’ve got samples of interersting DC/DC converter from TI: TPS61040. Main application is to drive small white LEDs from a battery cell or two. Input voltage range is from 1,8V to 6V. Ideal for two AA or single Li-xx cell. Schematics is very simple. Only few external components are required: a coil, caps and schottky diode: