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ST7LITE0xxx MICROCONTROLLED BALLAST

4 APPLICATION BOARD

On the application board there are two jumpers (J13 and J14) used to select the proper micro-

controller parameters for the lamp power or lamp type selection. Care must be taken that the

ballast is programmed for the nominal lamp power, because if a wrong lamp is selected, the

microcontroller will always try to provide a selected power (for example 58W into an 18W tube

lamp) which could damage the lamp.

4.1 OUTLOOK

The microcontroller solution with closed loop control allows in principle the detection of the

lamp type or power of the lamp inserted. Since this feature requires very detailed know-how of

lamp physics it is not implemented in the present version of this demo. An experienced ballast

designer however will be able to implement this feature and avoid the limitations described

above.