Wired OR

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TomasL
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Wired OR

Post by TomasL »

I am trying to do some design where I need to tie several outputs together, using wired-or technology
I am using ECL hence Open Emiter, and by default all inputs is pulled down to low with resistors.

Now it seems that all output symbols only can have two states High or Low, is it possible to create an output that can have High and High-Z instead.
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admin
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Re: Wired OR

Post by admin »

Hi,
Of course, it’s possible. There are two tristate elements available for you they are between Not and And elements.
TomasL
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Re: Wired OR

Post by TomasL »

Well, Tristate is not what I am, looking for, since they require an extra control-signal.
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Re: Wired OR

Post by admin »

Is it what you are looking for?
High-HighZ.Jpeg
High-HighZ.Jpeg (4.22 KiB) Viewed 9113 times
Please look at the circuit attached
The dash in the probe means high impedance.
Attachments
High-HighZ.CircuitProject
(3.22 KiB) Downloaded 402 times
TomasL
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Re: Wired OR

Post by TomasL »

Ok, that might be usable, what happens to the inputs when the connected outputs is HiZ, are they pulled low by default.
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Re: Wired OR

Post by admin »

It the same as just disconnect the input. For And it treated as 1 for Or as 0.
TomasL
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Re: Wired OR

Post by TomasL »

Ok, so in the ORgate the input is pulled low.
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