Ballast controller cuts 30% external components

STMicroelectronics reveals the L6520, a ballast controller that claims to be the first device to give the choice of using low-cost bipolar power switches without compromising reliability, offering high-energy efficiency and integrating important features on-chip to save design time and cost, while reducing BOM costs.

The IC can be used with a wide range of lamp topologies, power ratings and has an extended temperature range from -25–85°C. It also fulfils the requirements of energy-saving regulations such as 'Energy Star'.

The L6520 embeds a digital control core, integrating all functions and protection, saving as much as 30 per cent of the external components required with alternative controllers. Integrated features include lamp end-of-life, over-current and over-voltage protection, choke saturation and hard switching. Accurate and programmable pre-heating improves lamp life, while BJTs storage time compensation avoids the risk of cross-conduction and makes the application more robust.

The devices join ST's family of energy-saving ballast ICs, which includes the L6574 with circuitry for controlling dimmable ballast and CFLs, and the L6585DE with built-in power-factor correction for use in high-end applications.

The L6520/1 is in volume production in the industry-standard SO-8 package, priced at Rs.31.25 ($0.70) for 1000 units. Alternative pricing options are available for larger orders.