MC74VHCT138ADTRG ON Semiconductor

MC74VHCT138A 3-to-8 Line Decoder The MC74VHCT138A is an advanced high speed CMOS 3to8 decoder fabricated with silicon gate CMOS technology. It achieves high speed operation similar to equivalent Bipolar Schottky TTL while maintaining CMOS low power dissipation. When the device is enabled, three Binary Select inputs (A0 A2) MC74VHCT138A FUNCTION TABLE LOGIC DIAGRAM Inputs Outputs 15 Y0 1 E3 E2 E1 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 14 A0 Y1 SELECT 13 X X H X X X HHH HHHH H 2 Y2 A1 INPUTS X H X X X X HHH HHHH H 12 ACTIVE-LOW Y3 3 L X X X X X HHH HHHH H A2 11 OUTPUTS Y4 H L L L L L L H H HHHH H 10 Y5 H L L L L H H L H HHHH H 9 H L L L H L HH L HHHH H Y6 7 H L L L H H HHH L HHH H Y7 H L L H L L HHH H L HH H 6 E3 H L L H L H HHH HH L H H ENABLE 5 H L L H H L HHH HHH L H INPUTS E2 H L L H H H HHH HHHH L 4 E1 H = high level (steady state) L = low level (steady state) X = dont care EXPANDED LOGIC DIAGRAM 15 Y0 14 Y1 13 Y2 1 A0 12 Y3 2 A1 11 Y4 3 A2 10 Y5 5 E2 4 9 E1 Y6 7 Y7 6 E3 IEC LOGIC DIAGRAM BIN/OCT DMUX 1 1 15 15 A0 Y0 A0 Y0 1 0 0 0 0 2 14 2 14 A1 Y1 A1 Y1 2 1 G 1 7 3 13 3 13 A2 Y2 A2 Y2 4 2 2 2 12 Y3 12 Y3 3 3 11 11 Y4 Y4 & & 4 4 6 10 6 10 E3 Y5 E3 Y5 5 5 EN E2 5 9 E2 5 9 Y6 Y6 6 6 E1 4 7 E1 4 7 Y7 Y7 7 7