DESCRIPTION
The enable input G can be used to disable the device so that the buses are effectively isolated. All inputs are equipped with protection circuits against static discharge and transient excess voltage. PIN CONNECTION AND IEC LOGIC SYMBOLS August 2001 1/11 M74HC643 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
PIN No 1 2, 3, 4, 5, 6, 7, 8, 9 18, 17, 16, 15, 14, 13, 12, 11 19 10 20 SYMBOL DIR A1 to A8 B1 to B8 NAME AND FUNCTION Directional Control Data Inputs/Outputs Data Inputs/Outputs G GND VCC Output Enable Input Ground (0V) Positive Supply Voltage TRUTH TABLE INPUTS G L L H X : Don’t Care Z : High Impedance FUNCTION DIR L H X A BUS OUTPUT INPUT Z B BUS INPUT OUTPUT Z OUTPUT Yn A=B B=A Z LOGIC DIAGRAM This logic diagram has not be used to estimate propagation delays 2/11 M74HC643 ABSOLUTE MAXIMUM RATINGS
Symbol VCC VI VO IIK IOK IO PD Tstg TL Supply Voltage DC Input Voltage DC Output Voltage DC Input Diode Current DC Output Diode Current DC Output Current Power Dissip...
STMicroelectronics
