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5V 3A PSU

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Ash View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ash Quote  Post ReplyReply Direct Link To This Post Posted: 23 Aug 2020 at 4:56pm
Please let me know when further details and photographs are available for this product. Once I finalise my needs, I will commit to a purchase. Thanks very much.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote peterb Quote  Post ReplyReply Direct Link To This Post Posted: 03 Sep 2020 at 7:14pm
I am now up against it and need a 5V linear PSU. 
Can you please give me a likely delivery date for your version?
I have to say that I am now at the point where I feel I must now make an upgrade.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ash Quote  Post ReplyReply Direct Link To This Post Posted: 11 Sep 2020 at 9:18pm
Anyone have a final version of this PSU yet? Any more pics?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote John C Quote  Post ReplyReply Direct Link To This Post Posted: 12 Sep 2020 at 9:09am
I should be starting work on these very soon. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ash Quote  Post ReplyReply Direct Link To This Post Posted: 12 Sep 2020 at 7:09pm
Great, I understand you are busy. I will do more research while I wait.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Graham Slee Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2020 at 9:46pm
Update:

After such a long time trying to get the cases made here in the UK, we expected the first production unit might throw a few problems at us. We always make the first of any product at a slow pace to understand any construction difficulty. But there was no problem there.

On test, it was a slightly different matter - the 3.3V output overvoltage protection network proved to be a lot more sensitive to those on the prototype and pre-production units. A few hours of socially distanced troubleshooting, by Skype, and we solved it.

A manufacturer made a component substitution (it happens a lot in electronics - especially after nearly a four years delay). Although the overvoltage crowbar thyristor shares an identical specification, the new unit's gate sensitivity is considerably higher when tested in real life. Usually, the avalanche characteristics of the reference Zener diode would have been sufficient for the trigger current to remain below the thyristor's sensitivity - in fact, on the 5V output, that was the case.

Not so the lower voltage Zener, which has much poorer avalanche characteristics, and in fact, it acts more like a chain of signal diodes than the near abrupt knee expected in a Zener. We have had to reduce the value of the gate firing load resistor to obtain a reliable shutdown. I can see this becoming an adjust-on-test (AOT) process.

Did I mention we had another problem? After three and a half years of trying to launch the product, the mains fuse documentation had disappeared, and my recalculation must have missed the mark just a bit! With 20 rear panels printed with what now turns out to be the wrong value, the first batch of power supplies will feature a sticker with the right value.

The good news is that John wants the first one ready for me to take photographs next week!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote BackinBlack Quote  Post ReplyReply Direct Link To This Post Posted: 01 Oct 2020 at 10:45pm
Good News indeed. Nice to hear those problems have been overcome. Very much looking forward to seeing the photos and in due course handling the real thing.

Ian
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