SN54ALS878A, SN54ALS879A

SN74ALS878A, SN74ALS879A

DUAL 4BIT DTYPE EDGETRIGGERED FLIPFLOPS WITH 3STATE OUTPUTS

SDAS062A − D2661, APRIL 1982 − REVISED MAY 1986

POST OFFICE BOX 655303

POST OFFICE BOX 1443

4

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

7 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input voltage

7 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Voltage applied to a disabled 3-state output

5.5 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating free-air temperature range:

SN54ALS878A, SN54ALS879A

−55

°C to 125°C

. . . . . . . . . . . . . . . .

SN74ALS878A, SN74ALS879A

0

°C to 70°C

. . . . . . . . . . . . . . . . . . .

Storage temperature range

−65

°C to 150°C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

recommended operating conditions

SN54ALS878A

SN54ALS879A

SN74ALS878A

SN74ALS879A

UNIT

MIN

NOM

MAX

MIN

NOM

MAX

UNIT

VCC

Supply voltage

4.5

5

5.5

4.5

5

5.5

V

VIH

High-level input voltage

2

2

V

VIL

Low-level input voltage

0.7

0.8

V

IOH

High-level output current

−1

− 2.6

mA

IOL

Low-level output current

12

24

mA

fclock

Clock frequency

’ALS878A

0

25

0

30

MHz

fclock

Clock frequency

’ALS879A

0

20

0

25

MHz

tw

Pulse duration

’ALS878A CLK high or low

20

16.5

ns

tw

Pulse duration

’ALS879A CLK high or low

25

20

ns

tsu

Setup time before CLK

↑

Data

15

15

ns

tsu

Setup time before CLK

↑

CLR

20

20

ns

th

Hold time after CLK

↑

Data

4

4

ns

th

Hold time after CLK

↑

CLR

0

0

ns

TA

Operating free-air temperature

−55

125

0

70

°

°C

electrical characteristics over recommended operating free-air temperature range (unless

otherwise noted)

SN54ALS878A

SN74ALS878A

PARAMETER

TEST CONDITIONS

SN54ALS879A

SN74ALS879A

UNIT

MIN

TYP†

MAX

MIN

TYP†

MAX

UNIT

VIK

VCC = 4.5 V,

II = − 18 mA

− 1.2

− 1.2

V

VCC = 4.5 V to 5.5 V,

IOH = − 0.4 mA

VCC −2

VCC −2

VOH

VCC = 4.5 V,

IOH = − 1 mA

2.4

3.3

V

VCC = 4.5 V,

IOH = − 2.6 mA

2.4

3.2

VOL

VCC = 4.5 V,

IOL = 12 mA

0.25

0.4

0.25

0.4

V

VOL

VCC = 4.5 V,

IOL = 24 mA

0.35

0.5

V

IOZH

VCC = 5.5 V,

VO = 2. 7 V

20

20

µA

IOZL

VCC = 5.5 V,

VO = 0.4 V

−20

−20

µA

II

VCC = 5.5 V,

VI = 7 V

0.1

0.1

mA

IIH

VCC = 5.5 V,

VO = 2.7 V

20

20

µA

IIL

VCC = 5.5 V,

VI = 0 .4 V

− 0.2

− 0.2

mA

IO‡

VCC = 5.5 V,

VO = 2.25 V

−30

−112

−30

−112

mA

Outputs high

14

23

14

23

ICC

VCC = 5.5 V

Outputs low

18

31

18

31

mA

Outputs disabled

20

33

20

33

† All typical values are at VCC = 5 V, TA = 25°C.

‡ The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.