M74HC238 Datasheet | STMicroelectronics

DESCRIPTION The M54/74HC238 is a high speed CMOS 3 to 8 line 2 decoder fabricated in silicon gate C MOS technology. It has the same high speed performance of LSTTL bined with true CMOS low power consumption. If the device is enabled, 3 binary select inputs (A, B and C) determine which one of outputs will go high. Enable input G1 is held ”Low” or either G2A or G2B is held ”High” decoding function is inhibited and all the 8 outputs go low. Three enable inputs are provided to ease cascade connection and application of this address decoder in memory systems. All inputs are equipped with protection circuits against static discharge and transient excess voltage. NC = No Internal Connection October 1993 1/10 M54/M74HC238 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION PIN No 1, 2, 3 4, 5 6 15, 14, 13, 12, 11, 10, 9, 7 8 16 SYMBOL A, B, C G2A G2B G1 Y0 to Y7 NAME AND FUNCTION Data Inputs Enable Input (Active LOW) Data Enable Input (Active HIGH) Outputs GND VCC Ground (0V) Positive Supply Voltage IEC LOGIC SYMBOLS TRUTH TABLE INPUTS ENABLE G2B X X H L L L L L L L L G2A X H X L L L L L L L L G1 L X X H H H H H H H H C X X X L L L L H H H H SELECT B X X X L L H H L L H H A X X X L H L H L H L H Y0 L L L H L L L L L L L Y1 L L L L H L L L L L L Y2 L L L L L H L L L L L OUTPUS Y3 L L L L L L H L L L L Y4 L L L L L L L H L L L Y5 L L L L L L L L H L L Y6 L L L L L L L L L H L Y7 L L L L L L L L L L H SELECTED OUTPUT NONE NONE NONE Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 X: Don’t Care 2/10 M54/M74HC238 LOGIC DIAGRAM ABSOLUTE MAXIMUM RATINGS Symbol VCC VI VO IIK IOK IO ICC or IGND PD Tstg TL Supply Voltage DC Input Voltage DC Output Voltage DC Input Diode Current DC Output Diode Current DC Output Source Sink Current Per Output Pin DC VCC or Ground Current Power Dissipation Storage Temperature Lead Temperature (10 sec) 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 m A m A m A m A m W o o Absolute Maximum...