Vacuum Fluorescent Displays for Car Audio Systems

The Vacuum Fluorescent Display (VFD), being a self-emissive display device featuring high luminance and excellent readability, has become widely used for automotive applications. The ability to drive it at 12V and to adjust the luminance with the duty cycle, give the VFD high consideration, especially for the display in the car audio system. The number of display segments for the car audio system has increased to more than 50. Adding new functions to the car audio system will increase the required number of display segments. In the 12V static drive system, the number of display segments determines, and equals, the number of driver integrated circuit (IC) output bits required. An increase in the number of anode terminals, required by the increase in display segments, will result in increases in system cost, assembly complexity, space-related problems, etc. This paper reports on attempts taken to solve these problems.