How to learn more about how this circuit works for education purpose? - Page 1
Forum section: electronics / projects

author: vitsensei
author_rank: Newbie
timestamp: July 08, 2018, 04:26:54 am
content: I'm studying EEE at university and want to learn more about this circuit that supposed to be taking in the password and disengaged the lock of a safe, for education purpose.Here are some pictures of it:https://imgur.com/gallery/oFgb2Bf/comment/1431661445Thank you.

author: IconicPCB
author_rank: Super Contributor
timestamp: July 08, 2018, 04:36:59 am
content: Dear Betty,Every time I see my boyfriend his pocket is bulging.He tells me he has a bottle in it.Does he love me?

author: Simon
author_rank: Unknown
timestamp: July 08, 2018, 02:57:43 pm
content: Quote from: blueskull on July 08, 2018, 04:39:20 amI felt like saying ditto! I mean here is a picture of a circuit board and a schematic would be a minimum for anyone to have an idea.........

author: leonababy
author_rank: Regular Contributor
timestamp: July 08, 2018, 03:54:53 pm
content: Quote from: blueskull on July 08, 2018, 04:38:14 amThis is a 5 star reply - much more than I expected to see, and far superior to the Bottle of the Bulge reply which left me scratching me head.

author: Simon
author_rank: Unknown
timestamp: July 08, 2018, 04:01:36 pm
content: To be honest a picture of the board guarantees nothing. The OP seems to be trying to do what teenagers and early newcomers do and try to learn by looking at an existing circuit. This can be educational but the question really is "how do I design an electronic lock". This in principle is probably not too difficult and there are possibly various ways to do it.

author: leonababy
author_rank: Regular Contributor
timestamp: July 08, 2018, 04:07:47 pm
content: Yes - I believe you are correct, and that explains why my initial expectation was that there was no way to address the OP's post. I didn't see it from the general electronics perspective of, "what do you see?" Good point.

author: mtdoc
author_rank: Super Contributor
timestamp: July 08, 2018, 04:24:22 pm
content: Quote from: leonababy on July 08, 2018, 03:54:53 pmI agree. While a schematic would be nice, the OP surely does not have one (and may not yet have the skills to create one) and in this case I don’t think it’s needed. Blueskull’s explanation is very clear.

author: james_s
author_rank: Super Contributor
timestamp: July 08, 2018, 04:37:18 pm
content: Anything with a COB or even a microcontroller is essentially useless for learning because there's no visibility into what the IC/firmware is doing. If you want to analyze a circuit you need something that is made of discrete components for which you can find datasheets to study.

author: Simon
author_rank: Unknown
timestamp: July 08, 2018, 04:42:21 pm
content: which is why I would recommend asking just how to make one. Blueskulls answer is to that question with some guessing from experience as to what is on the board.

author: Simon
author_rank: Unknown
timestamp: July 08, 2018, 04:44:39 pm
content: I did an electronic lock in highschool as an end of year project. I used window comparators with 2 resistors in a stereo plug. This was after trying to do some complicated digital design aond the asshole in the electronics lab overetching my PCB so i just went home and made the comparator version up on some veroboard.

author: mtdoc
author_rank: Super Contributor
timestamp: July 08, 2018, 04:49:48 pm
content: Quote from: james_s on July 08, 2018, 04:37:18 pmI guess it depends on the OPs goal. It’s true, you’ll not learn anything about how the MCU functions from this and surely its function could be reproduced with discrete components, but I took the question as wanting to understand the circuit interfacing with the MCU - which can be easily seen and function deduced from the 2 photos.

author: james_s
author_rank: Super Contributor
timestamp: July 08, 2018, 04:59:52 pm
content: Yeah I suppose it's not clear. I see the circuit outside of the blob as being so trivial that it's not of any real interest but I suppose to a complete beginner there might be something to learn there.