4-54

FAST AND LS TTL DATA

MC54/74F138

GUARANTEED OPERATING RANGES

Symbol

Parameter

Min

Typ

Max

Unit

VCC

Supply Voltage

54, 74

4.5

5.0

5.5

V

TA

Operating Ambient Temperature Range

54

–55

25

125

°C

74

0

25

70

IOH

Output Current — High

54, 74

–1.0

mA

IOL

Output Current — Low

54, 74

20

mA

DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)

Limits

Symbol

Parameter

Min

Typ

Max

Unit

Test Conditions

VIH

Input HIGH Voltage

2.0

V

Guaranteed Input HIGH Voltage

VIL

Input LOW Voltage

0.8

V

Guaranteed Input LOW Voltage

VIK

Input Clamp Diode Voltage

–1.2

V

VCC = MIN, IIN = –18 mA

VOH

Output HIGH Voltage

54, 74

2.5

V

IOH = –1.0 mA

VCC = 4.50 V

74

2.7

V

IOH = –1.0 mA

VCC = 4.75 V

VOL

Output LOW Voltage

0.5

V

IOL = 20 mA

VCC = MIN

IIH

Input HIGH Current

20

µA

VCC = MAX, VIN = 2.7 V

0.1

mA

VCC = MAX, VIN = 7.0 V

IIL

Input LOW Current

–0.6

mA

VCC = MAX, VIN = 0.5 V

IOS

Output Short Circuit Current (Note 2)

–60

–150

mA

VCC = MAX, VOUT = 0 V

ICC

Power Supply Current

20

mA

VCC = MAX

NOTES:

1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable device type.

2. Not more than one output should be shorted at a time, nor for more than 1 second.

AC CHARACTERISTICS

54/74F

54F

74F

TA = +25 °C

TA = +25°C to +125°C

TA = 0°C to 70°C

Levels

VCC = +5.0 V

VCC = 5.0 V ±10%

VCC = 5.0 V ±10%

of

CL = 50 pF

CL = 50 pF

CL = 50 pF

Symbol

Parameter

Delay

Min

Max

Min

Max

Min

Max

Unit

tPLH

Propagation Delay,

3

3.0

7.5

3.0

12

3.0

8.5

ns

tPHL

Address to Output

3.0

8.0

3.0

9.5

3.0

9.0

tPLH

Enable to Output

2

3.5

7.0

3.5

11

3.5

8.0

ns

tPHL

E1 or E2

3.0

7.0

3.0

8.0

3.0

7.5

tPLH

Enable to Output

3

4.0

8.0

4.0

12.5

4.0

9.0

ns

tPHL

E3

3.5

7.5

3.5

8.5

3.5

8.5

FUNCTIONAL DESCRIPTION

The decoder accepts three binary weighted inputs (AO, A1,

A2) and when enabled provides eight mutually exclusive

active LOW outputs (O0–O7). The F138 features three Enable

inputs, two active LOW (E1, E2) and one active HIGH (E3). All

outputs will be HIGH unless E1 and E2 are LOW and E3 is

HIGH. This multiple enable function allows easy parallel

expansion of the device to a 1-of-32 (5 lines to 32 lines)

decoder with just four F138s and one inverter.

The F138 can be used as an 8-output demultiplexer by

using one of the active LOW Enable inputs as the data input

and the other Enable inputs as strobes. The Enable inputs

which are not used must be permanently tied to their

appropriate active HIGH or active LOW states.