74ALS257

INTEGRATED CIRCUITS 74ALS257/74ALS258 Data selector/multiplexer Product specification IC05 Data Handbook 1991 Feb 08 Philips Semiconductors Philips Semiconductors Product specification Data selector/multiplexer 74ALS257 Quad 2-input data selector, non-inverting (3-State) 74ALS258 Quad 2-input data selector, inverting (3-State) DESCRIPTION The 74ALS257 is a quad 2-input multiplexer which selects 4 bits of data from one of two sources under the control of a common select input (S). The output enable input (OE) is active when Low. When OE is High, all of the outputs (Yn) are forced to a High impedance state (3-State) regardless of all other input conditions. Moving data from two registers to a common output bus is a typical use of the 74ALS257. The state of the select input determines the particular register from which data comes. The device is the logic implementation of 4-pole, 2-position switch where the position of the switch is determined by the logic levels supplied to the select input. The 74ALS258 is similar but has inverting outputs (Yn). TYPE 74ALS257 74ALS258 74ALS257/74ALS258 TYPICAL PROPAGATION DELAY 7.0ns 7.0ns TYPICAL SUPPLY CURRENT (TOTAL) 7mA 7mA ORDERING INFORMATION ORDER CODE DESCRIPTION COMMERCIAL RANGE VCC = 5V ±10%, Tamb = 0°C to +70°C 74ALS257N, 74ALS258 74ALS257D, 74ALS258D 74ALS257DB, 74ALS258DB DRAWING NUMBER SOT38-4 SOT109-1 SOT338-1 16-pin plastic DIP 16-pin plastic SO 16-pin plastic SSOP Type II INPUT AND OUTPUT LOADING AND FAN-OUT TABLE P...