器件名称:
74HCT258D
功能描述:
Quad 2-input multiplexer; 3-state; inverting
文件大小:
83.87KB 共16页
简 介:
INTEGRATED CIRCUITS DATA SHEET 74HC/HCT258 Quad 2-input multiplexer; 3-state; inverting Product specication File under Integrated Circuits, IC06 1999 Sep 02 Philips Semiconductors Product specication Quad 2-input multiplexer; 3-state; inverting FEATURES Inverting data path 3-state outputs interface directly with system bus Output capability: bus driver ICC category: MSI. GENERAL DESCRIPTION The 74HC/HCT258 are high-speed Si-gate CMOS devices and are pin compatible with Low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A. The 74HC/HCT258 have four identical 2-input multiplexers with 3-state outputs, which select 4 bits of data from two sources and are controlled by a common data select input (S). The data inputs from source 0 (1I0 to 4I0) are selected when input S is LOW and the data inputs from source 1 (1I1 to 4I1) are selected when S is HIGH. QUICK REFERENCE DATA GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns. 1Y = OE × ( 1I 1 × S + 1I 0 × S ) 2Y = OE × ( 2I 1 × S + 2I 0 × S ) 3Y = OE × ( 3I 1 × S + 3I 0 × S ) 4Y = OE × ( 4I 1 × S + 4I 0 × S ) 74HC/HCT258 Data appears at the outputs (1Y to 4Y) in inverted form from the select inputs. The ‘258’ is the logic implementation of a 4-pole, 2-position switch, where the position of the switch is determined by the logic levels applied to S. The outputs are forced to a high impedance OFF-state when OE is HIGH. The logic equations for the outputs are: The ‘258’ is identical to the ‘257’ bu……
