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Standard Products

UT54ACS264/UT54ACTS264

Look-Ahead Carry Generators for Counters

Datasheet

November 2010

www.aeroflex.com/logic

FEATURES

Performs look-ahead carry across n-bit counters

Accommodates active-high or active-low carry

Improves cascaded counters system performance

1.2μ CMOS

- Latchup immune

High speed

Low power consumption

Single 5 volt supply

Available QML Q or V processes

Flexible package

- 16-pin DIP

- 16-lead flatpack

UT54ACS264- SMD 5962-96576

UT54ACTS264 - SMD 5962-96577

DESCRIPTION

The UT54ACS264 and the UT54ACTS264 are look-ahead gen-

erators designed specifically to perform a carry-anticipate across

any number of n-bit counters, thus increasing system clock fre-

quency. A carry enable CE, and carry outputs RCOA and RCOB

are provided for n-bit cascading.

Use the counter with either active-high-carry or active-low-car-

ry counters. For active-high-carry counters, CE is active high,

the A set of inputs and output RCOA are used. The B set of

inputs are connected to a low logic level. For active-low-carry

counters, CE is active low, the B set of inputs and output RCOB

are used. The A set of inputs are connected to a high logic level.

The devices are characterized over full military temperature

range of -55

°C to +125°C.

PINOUTS

16-Pin DIP

Top View

16-Lead Flatpack

Top View

1

2

3

4

5

7

6

16

15

14

13

12

10

11

A1

B1

A0

B0

A3

B3

RCOB

B2

A2

CE

C0

C1

RCOA

8

9

C2

1

2

3

4

5

7

6

16

15

14

13

12

10

11

A1

B1

A0

B0

A3

B3

RCOB

B2

A2

CE

C0

C1

RCOA

C2

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