ML4831

The ML4831 is a complete solution for a dimmable, high power factor, high efficiency electronic ballast. Contained in the ML4831 are controllers for "boost" type power factor correction as well as for a dimming ballast.

The Power factor circuit uses the average current sensing method with a gain modulator and over-voltage protection. This system produces power factors of better than 0.99 with low input current THD at > 95% efficiency. Special care has been taken in the design of the ML4831 to increase system noise immunity by using a high amplitude oscillator, and a current fed multiplier. An over-voltage protection comparator inhibits the PFC section in the event of a lamp out or lamp failure condition.

The ballast section of ML4831 provides for programmable starting scenarios with programmable preheat and lamp out-ofsocket interrupt times. The IC controls lamp output through either frequency modulation using lamp current feedback.

The ML4831 is designed using Micro Linear's Semi- Standard tile array technology. Customized versions of this IC, optimized to specific ballast architectures can be made available. Contact Micro Linear or an authorized representative for more information.