DESCRIPTION
PIN No SYMBOL NAME AND FUNCTION 1 SELECT Common Data Select Input 2, 5, 14, 11 1A to 4A Data Input From Source A 3, 6, 13, 10 1B to 4B Data Input From Source B 4, 7, 12, 9 1Y to 4Y 3 State Multiplexer Outputs 15 OE 3 State Output Enable Inputs (Active Low) t(s)TRUTH TABLE roducOE PH teL leL oL sL bX : Don’t Care OZ : High Impedance Obsolete Product(s) -LOGIC DIAGRAM 8 16 INPUTS SELECT X L L H H A X L H X X GND Vcc Ground (0V) Positive Supply Voltage OUTPUT BY XZ XL XH LL HH This logic diagram has not be used to estimate propagation delays 2/11 M74HC257 ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit VCC Supply Voltage -0.5 to +7 V VI DC Input Voltage -0.5 to VCC + 0.5 V VO DC Output Voltage -0.5 to VCC + 0.5 V IIK DC Input Diode Current ± 20 mA IOK DC Output Diode Current ± 20 mA IO DC Output Current ± 35 mA ICC or IGND DC VCC or Ground Current ± 70 mA PD Power Dissipation 500(*) mW )Tstg Storage Temperature -65 to +150 °C t(sTL Lead Temperature (10 sec) 300 °C ABSOLUTE MAXIMUM RATINGS
are those values beyond which damage to the device may occur.
STMicroelectronics
