DESCRIPTION
All inputs are equipped with protection circuits against static discharge and transient excess voltage. PIN CONNECTION AND IEC LOGIC SYMBOLS August 2001 1/8 M74HC21 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION
PIN No 1, 9 2, 10 3, 11 4, 12 5, 13 6, 8 7 14 SYMBOL 1A to 2A 1B to 2B N.C. 1C to 2C 1D to 2D 1Y to 2Y GND VCC NAME AND FUNCTION Data Inputs Data Inputs Not Connected Data Inputs Data Inputs Data Outputs Ground (0V) Positive Supply Voltage TRUTH TABLE A L X X X H B X L X X H C X X L X H D X X X L H Y L L L L H ABSOLUTE MAXIMUM RATINGS
Symbol VCC VI VO IIK IOK IO Supply Voltage DC Input Voltage DC Output Voltage DC Input Diode Current DC Output Diode Current DC Output Current Parameter Value -0.5 to +7 -0.5 to VCC + 0.5 -0.5 to VCC + 0.5 ± 20 ± 20 ± 25 ± 50 500(*) -65 to +150 300 Unit V V V mA mA mA mA mW °C °C ICC or IGND DC VCC or Ground Current PD Power Dissipation Tstg TL Storage Temperature Lead Temperature (10 sec) ABSOLUTE MAXIMUM RATINGS
are those values beyond which damage to the device may occur.
STMicroelectronics
