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Electronics => Beginners => Topic started by: wiresaho on May 29, 2024, 12:12:59 pm

Title: diode latch
Post by: wiresaho on May 29, 2024, 12:12:59 pm
Is it possible to make a latch with diodes   -  I saw this -> https://www.youtube.com/watch?v=MMy_GhyobDQ (https://www.youtube.com/watch?v=MMy_GhyobDQ)

Or is it including transistors with it to get the memory bits?
Title: Re: diode latch
Post by: Psi on May 29, 2024, 12:20:18 pm
You can make gates out of just diodes, but there is no amplification, no small current able to drive larger current.
So I believe they still use transistors as buffers/inverters. Otherwise you can't series diode-based gates together without absurd current requirements from each additional gate adding more draw through the gates before it.
Title: Re: diode latch
Post by: ledtester on May 29, 2024, 12:23:25 pm
A full writeup of the Diode Clock, design files and LTspice simulation files may be found here:

https://hackaday.io/project/11677-the-diode-clock#:~:text=DDL%20Devices,grab%20files%20here%3A (https://hackaday.io/project/11677-the-diode-clock#:~:text=DDL%20Devices,grab%20files%20here%3A)

(scroll down to "DDL Devices")

Here is the datasheet of the hex NOR board:

https://cdn.hackaday.io/files/11677499588768/DDL01_datasheet.pdf (https://cdn.hackaday.io/files/11677499588768/DDL01_datasheet.pdf)

and here is the schematic of a NOR gate from the datasheet:

(https://www.eevblog.com/forum/beginners/diode-latch/?action=dlattach;attach=2257246)

Read the datasheet for a detailed desciption of how it works. Note that V_RF is an AC source operating in the MHz range.
Title: Re: diode latch
Post by: wiresaho on May 29, 2024, 01:56:48 pm
If it didn't have inductors in it,  it would probably work hydraulicly and pneumaticly as well.

But they do have pneumatic "transistors" as well.
Title: Re: diode latch
Post by: coromonadalix on May 29, 2024, 04:50:16 pm
lolll   wow    but consumes almost 5  amps  ...  current hungry for sure
Title: Re: diode latch
Post by: David Hess on May 30, 2024, 12:01:38 am
You can make gates out of just diodes, but there is no amplification, no small current able to drive larger current.
So I believe they still use transistors as buffers/inverters. Otherwise you can't series diode-based gates together without absurd current requirements from each additional gate adding more draw through the gates before it.

Negative resistance devices can be used in place of amplification, like tunnel diodes, DIACs, or 4 layer diodes.  Neon bulbs can also be used.

Title: Re: diode latch
Post by: Psi on May 30, 2024, 08:59:24 am
You can make gates out of just diodes, but there is no amplification, no small current able to drive larger current.
So I believe they still use transistors as buffers/inverters. Otherwise you can't series diode-based gates together without absurd current requirements from each additional gate adding more draw through the gates before it.

Negative resistance devices can be used in place of amplification, like tunnel diodes, DIACs, or 4 layer diodes.  Neon bulbs can also be used.

Interesting.