© Semiconductor Components Industries, LLC, 2006

July, 2006 − Rev. 6

1

Publication Order Number:

SN74LS90/D

SN74LS90

DECADE COUNTER;

DIVIDE-BY-TWELVE

COUNTER;

4-BIT BINARY COUNTER

The SN54 / 74LS90, SN54 / 74LS92 and SN54 / 74LS93 are

high-speed 4-bit ripple type counters partitioned into two sections.

Each counter has a divide-by-two section and either a divide-by-five

(LS90), divide-by-six (LS92) or divide-by-eight (LS93) section which

are triggered by a HIGH-to-LOW transition on the clock inputs. Each

section can be used separately or tied together (Q to CP) to form BCD,

bi-quinary, modulo-12, or modulo-16 counters. All of the counters

have a 2-input gated Master Reset (Clear), and the LS90 also has a

2-input gated Master Set (Preset 9).

Binary

PIN NAMES

LOADING (Note a)

HIGH

LOW

Clock (Active LOW going edge) Input to

÷2 Section

0.5 U.L.

1.5 U.L.

Clock (Active LOW going edge) Input to

÷5 Section (LS90), ÷6 Section (LS92)

0.5 U.L.

2.0 U.L.

Clock (Active LOW going edge) Input to

÷8 Section (LS93)

0.5 U.L.

1.0 U.L.

Master Reset (Clear) Inputs

0.5 U.L.

0.25 U.L.

Master Set (Preset-9, LS90) Inputs

0.5 U.L.

0.25 U.L.

Output from ÷2 Section (Notes b & c)

10 U.L.

5 (2.5) U.L.

Outputs from ÷5 (LS90), ÷6 (LS92),

÷8 (LS93) Sections (Note b)

10 U.L.

5 (2.5) U.L.

NOTES:

a. 1 TTL Unit Load (U.L.) = 40 μA HIGH/1.6 mA LOW.

b. The Output LOW drive factor is 2.5 U.L. for Military, (54) and 5 U.L. for commercial (74)

http://onsemi.com

DECADE COUNTER;

DIVIDE-BY-TWELVE COUNTER;

4-BIT BINARY COUNTER

LOW POWER SCHOTTKY

J SUFFIX

CERAMIC

CASE 632-08

N SUFFIX

PLASTIC

CASE 646-06

14

1

14

1

ORDERING INFORMATION

SN54LSXXJ

Ceramic

SN74LSXXN

Plastic

SN74LSXXD

SOIC

14

1

D SUFFIX

SOIC

CASE 751A-02

LOGIC SYMBOL

12

2

GND = PIN 10

NC = PINS 4, 13

GND = PIN 10

NC = PINS 2, 3, 4, 13

GND = PIN 10

NC = PIN 4, 6, 7, 13

LS90

LS92

LS93

67

12

14

1

12

23

MS

12 9 8 11

6 7

14

1

1

12

9 8

11

14

1

23

12 9 8 11