The DS3984 and DS3988 are multi-channel Cold-Cathode Fluorescent Lamp (CCFL) controllers. The key variable in designing an optimal system with the DS3984 and DS3988 is the selection of the transformer turns ratio. This application note describes how the transformer turns ratio varies with different CCFL lamps and DC supply voltages and it provides a quick look-up table to help the user quickly select a transformer turns ratio that will work well in their design. ……