Philips Lighting, LED platform development was a department within Philips Lighting that did predevelopment of LED drivers and modules. Their focus was mainly on low cost, retrofit and dimmer/ballast compatibility.
In general linear converters have a low efficiency, but in combination with a tapped LED string a high efficiency and power factor can be achieved. Lighting wanted to investigate the possibilities of the so called tapped linear driver and if it was suitable for retrofit and dimmer compatible lamps.
As Electronics Designer I was responsible for investigating the tapped linear driver concept and for designing drivers based on it.
Activities I did for this project were:
- Analyse what is needed to achieve dimmer compatibility
- Design a tapped linear driver
- Test and validate the design
- Create design tools in excel and matlab
- Document the design and design procedure
- Evaluate and bench mark commercially available tapped linear driver solutions
I created and evaluated tapped linear driver proposals for a number of products and documented the outcome.