View sn74ls48 datasheet:

SN54/74LS48 BCD TO 7-SEGMENT DECODER The SN54 /74LS48 is a BCD to 7-Segment Decoder consisting of NAND gates, input buffers and seven AND-OR-INVERT gates. Seven NAND gates BCD TO 7-SEGMENT and one driver are connected in pairs to make BCD data and its complement available to the seven decoding AND-OR-INVERT gates. The remaining DECODER NAND gate and three input buffers provide lamp test, blanking input/ripple- LOW POWER SCHOTTKY blanking input for the LS48. The circuit accepts 4-bit binary-coded-decimal (BCD) and, depending on the state of the auxiliary inputs, decodes this data to drive other components. The relative positive logic output levels, as well as conditions required at the auxiliary inputs, are shown in the truth tables. The LS48 circuit incorporates automatic le