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Encoders and Decoders

ENGI 251ELEC 241

General Decoder Diagram

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Decoder for the Binary Pattern 1001

Decoder

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The 74ALS138 Decoder

3-line-to-8-line (1-of-8) Decoder

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The 74ALS138 Decoder

Four 74AS138s forming a 1-of-32 decoder

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7442A BCD-to-Decimal Decoder/Driver

7442 BCD-to-decimal decoder

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7442 Waveform Diagram

A 4-line-to-16-line Decoder/DeMux

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74154 4-line-to-16-line Decoder/DeMux

Function Table

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A 5-line-to-32-line Decoder

Seven Segment Display

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7-Segment Display

LED 7-segment Display with Driver Circuitry

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LCD Display

Driving an LCD a 7-segment Display

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Passive Matrix LCD

Encoders

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General Encoder Diagram

An Octal-to-Binary (8-line-to-3-line) Encoder

For proper operation, only one input should be active at one time

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74147 Decimal-to-BCD Priority Encoder

Decimal-to-BCD Switch Encoder