SN54HC161, SN74HC161

4BIT SYNCHRONOUS BINARY COUNTERS

SCLS297D − JANUARY 1996 − REVISED SEPTEMBER 2003

1

POST OFFICE BOX 655303

SN54HC161 ...J OR W PACKAGE

SN74HC161 . . . D, N, NS, OR PW PACKAGE

(TOP VIEW)

32

1 20 19

910 11 12 13

4

5

6

7

8

18

17

16

15

14

NC

A

B

NC

C

D

SN54HC161 . . . FK PACKAGE

(TOP VIEW)

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

CLR

CLK

A

B

C

D

ENP

GND

RCO

ENT

LOAD

NC − No internal connection

description/ordering information

These synchronous, presettable counters feature an internal carry look-ahead for application in high-speed

counting designs. The ’HC161 devices are 4-bit binary counters. Synchronous operation is provided by having

all flip-flops clocked simultaneously so that the outputs change coincident with each other when so instructed

by the count-enable (ENP, ENT) inputs and internal gating. This mode of operation eliminates the output

counting spikes that are normally associated with synchronous (ripple-clock) counters. A buffered clock (CLK)

input triggers the four flip-flops on the rising (positive-going) edge of the clock waveform.

ORDERING INFORMATION

TA

PACKAGE†

ORDERABLE

PART NUMBER

TOP-SIDE

MARKING

PDIP − N

Tube of 25

SN74HC161N

SN74HC161N

Tube of 40

SN74HC161D

SOIC − D

Reel of 2500

SN74HC161DR

HC161

−40

°C to 85°C

SOIC − D

Reel of 250

SN74HC161DT

HC161

−40

°C to 85°C

SOP − NS

Reel of 2000

SN74HC161NSR

HC161

Tube of 90

SN74HC161PW

TSSOP − PW

Reel of 2000

SN74HC161PWR

HC161

TSSOP − PW

Reel of 250

SN74HC161PWT

HC161

CDIP − J

Tube of 25

SNJ54HC161J

SNJ54HC161J

−55

°C to 125°C

CFP − W

Tube of 150

SNJ54HC161W

SNJ54HC161W

−55 C to 125 C

LCCC − FK

Tube of 55

SNJ54HC161FK

SNJ54HC161FK

† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are

available at www.ti.com/sc/package.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

Copyright

 2003, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

On products compliant to MILPRF38535, all parameters are tested

unless otherwise noted. On all other products, production

processing does not necessarily include testing of all parameters.