A Digital Constant Current Power LED Driver

Focus:

The PIC12HV615, an 8-pin microcontroller (MCU) with many analog features, is used to build a digitally controlled buck converter that drives one or more 1-W LEDs so long as input voltage exceeds the VF of the LEDs being driven. To regulate drive current to the LED(s) at a constant current level, the MCU runs a proportional-integral (PI) controller algorithm. Besides regulating current to the LED(s), the MCU can be used to monitor other signals such as temperature of an LED to ensure that it remains within its acceptable operating temperature range.

What you’ll learn:

• How to build a digitally controlled buck converter for driving a 1-W LED

Notes:

Microchip Technology application note AN1138. A video demonstration of the demo board and software developed for this application note is available on YouTube at http://www.youtube.com/watch?v=wr-jVDy4fjQ

View the Source

Author & Publication:

Stephen Bowling, Applications Segment Group, Microchip Technology , Vendor website, Oct 05 2007

This article summary appears
in the HOW2POWER Design Guide.

The Design Guide offers
organized access to
hundreds of articles
on dozens of power conversion
and power management topics.

The Design Guide search results
include exclusive summaries
and accurate "how to" analysis
to help you make faster,
more informed decisions.

Search
for more articles