Test of Yihua 502D PSU.
Added 2018-04-06 01:52:33 +0000 UTChttps://www.youtube.com/watch?v=rz-ndgC6BJ4
It's kind of a fail, but also a hint at hackability and an understated power rating.
In hindsight I'm wondering if the coil and shunt resistance of the meter was affecting the voltage drop with increasing current.
I'm a bit surprised at an optoisolator running at 50 degrees Celsius! Now I'm thinking it would have been interesting to increase the LED current to see if the better coupling reduced the optoisolator dissipation.
The control chip is in an 8-pin package, but in reality only has three connections and uses six of the pins for heatsinking.
Despite being stated as a 200-240V unit it performed well up to the full 2A on 110V and despite being rated for 1A it does seem to deliver 2A with enough ease to consider as being continuously rated. Especially with a vertical power PCB with cooling vents above and below.
Comments
"China Export" / "Caveat Emptor". Pretty much the same thing. :) I'll just leave this here, for those who haven't seen it before (although interestingly, it appears from the video that Yihua actually got the logotype spacing correct for the CE sticker on this product) : <a href="https://f2labs.com/technotes/2016/07/18/ce-marking-and-the-china-export-mark/" rel="nofollow noopener" target="_blank">https://f2labs.com/technotes/2016/07/18/ce-marking-and-the-china-export-mark/</a>
Chris Talbot
2018-04-14 01:34:49 +0000 UTCOoh, that one's ugly. I liked the linked listing to power supply modules that had serious isolation defects on their PCBs.
Big Clive
2018-04-08 00:36:43 +0000 UTCI see eBay has a 3-amp version in a cheery blue casing as well. <a href="https://www.ebay.com/itm/SUNSHINE-P-0503C-Mini-5V-3A-Regulated-DC-Power-Supply-SMPS-for-Cellphone-Repair/282165407748?hash=item41b25e7004:g:NKUAAOSwMgdXz9K" rel="nofollow noopener" target="_blank">https://www.ebay.com/itm/SUNSHINE-P-0503C-Mini-5V-3A-Regulated-DC-Power-Supply-SMPS-for-Cellphone-Repair/282165407748?hash=item41b25e7004:g:NKUAAOSwMgdXz9K</a>~
Michael Thompson
2018-04-07 22:53:55 +0000 UTCDespite the 4.55-4.7V output, technically it's still within USB spec. If it went below 4.4V at any point with a reasonable load, then it'd be a complete fail. Edit: Funnily enough, an Aliexpress listing (as well as yihua-gz website) list output voltage as "5V-6%" which would be 4.7V.
2018-04-07 18:41:48 +0000 UTCThose tunes are know as "Ear Worms" which probably makes them sound worse.
2018-04-06 20:24:34 +0000 UTC"Bah dumb a dum" was stuck in my head yesterday at work, good stuff when doing something monotonous (computer nonsense)
2018-04-06 07:52:01 +0000 UTCIs the 1amp rating referring to the 240v input? Though that would imply a 48amp output so maybe not. (!)
David Glover-Aoki
2018-04-06 04:11:55 +0000 UTC
