4-40

Features

• Provides Direct Control of Up to 7 Input and 7 Output

Devices When used with a CDP1800-Series Micropro-

cessor

• CHIP ENABLE (CE) Allows Easy Expansion for Multi-

level I/O Systems

Description

The CDP1853/3 and CDP1853C/3 are high-reliability 1 of 8

decoders designed for use in general purpose microproces-

sor systems. These devices, which are functionally identical,

are specifically designed for use as gated N-bit decoders

and interface directly with the 1800-Series microprocessors

without additional components. The CDP1853/3 has a rec-

ommended operating voltage range of 4V to 10.5V, and the

CDP1853C/3 has a recommended operating voltage range

of 4V to 6.5V.

When CHIP ENABLE (CE) is high, the selected output will be

true (high) from the trailing edge of CLOCK A (high-to-low

transition) to the trailing edge of CLOCK B (high-to-low

transition). All outputs will be low when the device is not

selected (CE = 0) and during conditions of CLOCK A and

CLOCK B as shown in Figure 2. The CDP1853/3 inputs N0,

N1, N2, CLOCK A, and CLOCK B are connected to 1800-

series microprocessor outputs N0, N1, N2, TPA, and TPB

respectively, when used to decode I/O commands as shown

in Figure 5. The CHIP ENABLE (CE) input provides the capa-

bility for multiple levels of decoding as shown in Figure 6.

The CDP1853/3 can also be used as a general purpose 1 of

8 decoder for I/O and memory system applications as shown

in Figure 4.

Pinout

16 LEAD SBDIP

TOP VIEW

Ordering Information

PACKAGE

TEMP. RANGE

5V

10V

PKG.

NO.

SBDIP

-

D16.3

14

15

16

9

13

12

11

10

1

2

3

4

5

7

6

8

CLK A

N0

N1

OUT 0

OUT 1

OUT 2

OUT 3

N2

CE

OUT 4

OUT 5

OUT 6

OUT 7

CLK B

March 1997

File Number

1713.2

CDP1853C/3

High-Reliability CMOS N-Bit 1 of 8 Decoder

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

http://www.intersil.com or 407-727-9207