The 74LS47 accepts four lines of BCD (8421) input data, generates their complements internally and decodes the data with seven AND-OR gates having open-collector outputs to drive indicator segments directly. Each segment output is guaranteed to sink 24 mA in the ON (LOW) state and withstand 15V in the OFF (HIGH) state with a maximum leakage current of 250 µA. Auxiliary inputs provided blanking, lamp test and cascadable zero-suppression functions.
