74LS173N

74LS173N 4-Bit D-Type Register with 3-State Outputs. This chip is a small 4-bit memory storage cell. It captures 4 bits of data on a clock signal and holds them. It features a "3-state" mode that can completely disconnect its output pins from a circuit, allowing multiple chips to safely share the same wire bus. [1, 2, 3, 4, 5]