discount-cactus / LVDC-Remake

Building an equivalent of the flight computer to the Saturn V rocket from the 1960's based on public documentation.
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Latch Design Trade Study #7

Closed discount-cactus closed 1 year ago

discount-cactus commented 1 year ago

The bistable storage latch on the LVDC project has been a persistent issue since the beginning so I am finally opening an issue specifically for tackling the design.

discount-cactus commented 1 year ago

Schematic of latch per the NASA documentation:

IMG_6590

discount-cactus commented 1 year ago

Design as of 3/30/23:

IMG_6596

discount-cactus commented 1 year ago

Design as of 4/2/23: The design was changed again and utilizes a CD4002BE quad 2-input NOR gate to simplify the circuit from 12 components to 1.

Screen Shot 2023-04-12 at 7 20 35 PM
discount-cactus commented 1 year ago

4/13/2023: Initial testing was done with the design and the circuit looks promising, however the outputs are inverted due to the IC being a dual 4-input NOR gate instead of an OR gate.

discount-cactus commented 1 year ago

4/15/2023: The previous comment is full of cap and the design with the CD4002BE dual 4-input NOR gate works. Progress on the LVDC will continue with this design.

Design: Latch_V3

00: CD4002BE_00

01: CD4002BE_01

10: CD4002BE_10

11: CD4002BE_11