SN74LS373N Latch, 74LS373, D Type Transparent, Tri State, 12 ns, 24 mA. The SN74LS373N is an octal D-type Transparent Latch with 3-state outputs. Designed specifically for driving highly capacitive or relatively low-impedance loads. The high-impedance 3-state and increased high-logic-level drive provide these registers with the capability of being connected directly to and driving the bus lines in a bus-organized system without need for interface or pull up components.