HD74AC138/HD74ACT138

Rev.2.00, Jul.16.2004, page 3 of 9

Logic Diagram

A2

A1

A0

E1

O0

O1

O2

O3

O4

O5

O6

O7

E2 E3

Please note that this diagram is provided only for the understanding of logic operations and should not be

used to estimate propagation delays.

Figure a: Expansion of 1-of-32 Decoding

A0

E

O0

O31

H

A1

A2

A3

A4

123

E

123

O0 O1 O2O3O4 O5O6 O7

E

123

A0 A1 A2

O0 O1 O2O3O4 O5O6 O7

A0 A1 A2

O0 O1 O2O3O4 O5O6 O7

A0 A1 A2

O0 O1 O2O3O4 O5O6 O7

A0 A1 A2

E

123

Õ04

Absolute Maximum Ratings

Item

Symbol

Ratings

Unit

Condition

Supply voltage

V

CC

–0.5 to 7

V

–20

mA

V

I = –0.5V

DC input diode current

I

IK

20

mA

V

I = Vcc+0.5V

DC input voltage

V

I

–0.5 to Vcc+0.5

V

–50

mA

V

O = –0.5V

DC output diode current

I

OK

50

mA

V

O = Vcc+0.5V

DC output voltage

V

O

–0.5 to Vcc+0.5

V

DC output source or sink current

I

O

±50

mA

DC V

CC or ground current per output pin

I

CC, IGND

±50

mA

Storage temperature

Tstg

–65 to +150

°C