74LS399, 74LS398 Datasheet (Motorola)

74LS399, 74LS398, QUAD 2-PORT REGISTER

The SN54 / 74LS398 and SN54 / 74LS399 are high-speed Quad 2-Port Registers.

They select four bits of data from two sources (Ports) under the control of a common Select Input (S).

The selected data is transferred to a 4-Bit Output Register synchronous with the LOW-to-HIGH transition of the Clock in-

74LS399 Features

* both Q and Q inputs, while the SN54 / 74LS399 has only Q outputs.

* Select From Two Data Sources

* Fully Positive Edge-Triggered Operation

* Both True and Complemented Outputs on SN54 / 74LS398

* Input Clamp Diodes Limit High-Speed Termination Effects CONNECTION DIAGR