Intel mcs-48 manual 8205

Models: mcs-48

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8205

HIGH SPEED 1 OUT OF8 BINARY DECODER

1/0 Port or Memory Selector

Simple Expansion - Enable Inputs

Hig"h Speed Schottky Bipolar Technology - 18 ns Max Delay

Directly Compatible with TTL Logic Circuits

Low Input Load. Current - 0.25 mA Max, 1/6 Standard TTL Input Load

Minimum Line Reflection - Low Voltage Diode Input Clamp

Outputs Sink 10 mA Min

16·PinDualln·LineCeramic or Plastic Package

The Intel'"8205 decoder can be used for expansion of systems which utilize input ports, output ports, and memory components with active low chip select input. When the 8205 is enabled, one of its 8 outputs goes "low", thus a single row of a memory system is selected. The 3·chipenable inputs on the 8205 allow easy system expansion. For very large systems, 8205 decoders can be cascaded such that each decoder can drive 8 other decoders for arbitrary memory expansions.

The 8205 is packaged in a standard 16-pin dual in-line package, and its performance is specified over the temperature range of oDe to +75°e, ambient. The use of Schottky barrierdlode clamped transistors to obtain fast switching speeds results in higher performance than equivalent devices made with a gold diffussion process.

PIN CONFIGURATION

Ao

 

16

V.cc

A,

 

15

0 0

A2

3

14

0,

E,

4

13

°2

 

 

8205

 

E2

5

12

0 3

E3

6

11

0.

0,

 

10

°5

GRD

8

 

0 6

PIN NAMES

AO· A2 ADDRESS INPUTS

E ,. E3 ENABLE INPUTS 00· 0, DECODED OUTPUTS

LOGIC SYMBOL

Ao

A,

A2

8205

E,

E2

EJ

ADDRESS

ENABLE

 

 

OUTPUTS

 

 

 

Ao

A,

A,

E,

E,

E3

0 1

2

3

0

6

)

L L L L L H L H H H H H H

H

H L

L

L

L

H H L

H H H H H

H

L

Ii L

L

L

H H H

L

H H H H H

H

H

L

L

L

H H H H L

H

H H

H

L

L

H L

L

H H H H H L

H H

H

H L

H L

L

H H H H H H L

H

H

l

H H

L

L

H H H H H H H L

H

H H H L L

H H H H H H H H

L

X X X L L

L

H H H H H H H

H

X X X

H L

L

H H H H H H H

H

X X X

L H

L

H H H H H H H

H

X X X

H H

L

H H H H H H H

H

X X X H L H H H H H H H H H

X X X

L H H H H H H H H H H

X X X

H H H H H H H H H H H

8-18

AFN-00204B-ol

Page 279
Image 279
Intel mcs-48 manual 8205