The input protection diodes are useful in certain party-line

plies turned off In such a system if a supply is turned off

and allowed to go to ground the equivalent input circuit

connected to that supply would be as follows

‘‘A’’ Devices

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Standard Devices

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This would be a problem in specific systems which might

possibly have the transmission lines biased to some poten-

tial greater than 14V Since this is not a widespread appli-

cation problem both the ‘‘A’’ and standard devices will be

available The ratings and characteristic specifications of

the ‘‘A’’ devices are the same as those of the standard

devices

The DS55107A feature the ‘‘A’’ device input stage

Schematic Diagrams

DS55107DS75107 DS75108 DS75208

TLF9446 – 11

Note 1

of the dual circuit is shown

Note 2

Indicates connections common to second half of dual circuit

Note 3

Components shown with dash lines are applicable to the DS55107 DS75207 and DS75107 only

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