Mini-test 12-5v DCDC USB Car Adapter #2 - Page 1
Forum section: electronics / general

author: dexters_lab
author_rank: Unknown
timestamp: July 20, 2013, 04:17:58 pm
content: another similar test tohttps://www.eevblog.com/forum/chat/mini-test-12-5v-dcdc-usb-car-adaptor/this time it's a cigar lighter adapter, dual socket one rated to 1A the other 2A. Ebay again, £4.29 from a UK seller. Looks like someone done a proper job on this one, maybe why it costs a little more than the others, funny how just a couple of quid can make all the difference!Wasn't able to test both outputs at the same time though.1A output:output load / output voltage / supply load (@12v)0ma / 5.10 / 10ma250ma / 5.01 / 120ma500ma / 4.97 / 240ma750ma / 4.93 / 350ma1000ma / 4.90 / 470ma2A output:output load / output voltage / supply load (@12v)0ma / 5.11 / 10ma500ma / 5.03 / 240ma1000ma / 5.00 / 470ma1500ma / 4.98 / 710ma2000ma / 4.97 / 960ma

author: quanttrom
author_rank: Regular Contributor
timestamp: July 25, 2013, 08:06:54 pm
content: sorry to bring up an old thread but I have been having a lot of issues with cheap car usb chargers and a picky phone (Nokia N900)Does this one say YIBOYUAN on it?

author: dexters_lab
author_rank: Unknown
timestamp: July 29, 2013, 08:17:53 am
content: No branding on the outside, not looked properly at the pcb yet

author: Psi
author_rank: Super Contributor
timestamp: July 29, 2013, 11:55:50 am
content: Nice to see someone else using a N900

author: quanttrom
author_rank: Regular Contributor
timestamp: July 29, 2013, 02:16:27 pm
content: Haha yeah, it's pretty much retired. I use it as a GPS on my motorcycle. When it's charging right it works like a charm

author: Psi
author_rank: Super Contributor
timestamp: July 29, 2013, 02:24:45 pm
content: im still using mine as a phone.Find me a modern phone that has the following things and ill consider upgrading.- flip/slide out qwerty kbd- IR receiver- IR transmitter- FM radio- FM transmitter- touchscreen that can support ultra fine pen touching (for clicking tiny buttons in 1920x1080 RDP/VNC session)- camera with good quality macro support. eghttp://psi.abcom.co.nz/n900macro1.jpghttp://psi.abcom.co.nz/n900macro2.jpgOtherwise it would be a downgrade

author: quanttrom
author_rank: Regular Contributor
timestamp: July 29, 2013, 06:22:16 pm
content: It's just sooo damn slooowww compared to any of the new phones. Anyways, lets not threadjack

author: peter.mitchell
author_rank: Super Contributor
timestamp: July 30, 2013, 07:54:11 am
content: Hahaha, i was going to comment simply on the phone, but was like "nah, nobody cares" but what do you know.. I like it because the system has system wide keyboard shortcuts like on a real computer, so you can copy/paste/whatever just with keyboard shortcuts, it's amazing! and the ability to pull up a cursor in the browser for mouseover features? I don't know of anything else with that either!

author: dexters_lab
author_rank: Unknown
timestamp: July 30, 2013, 12:11:07 pm
content: Its shocking how many useful features disappear in new phones. Only today i rejoiced that android 4.3 now has dialpad searches, a feature i used all the time on my now retired windows mobile 6 based htc phone.

author: TopLoser
author_rank: Unknown
timestamp: July 30, 2013, 10:53:20 pm
content: Looks nice, have you got a link to the Ebay auction to save me trudging though 10,000 possibles?!

author: dexters_lab
author_rank: Unknown
timestamp: July 30, 2013, 11:00:40 pm
content: Sorry!http://pages.ebay.com/link/?nav=item.view&id=370841518731

author: TopLoser
author_rank: Unknown
timestamp: July 30, 2013, 11:13:33 pm
content: Ta! Bought one. Be nice to find out if you can get full rated current from both outputs at once.

author: jh15
author_rank: Frequent Contributor
timestamp: August 15, 2013, 02:35:29 pm
content: Does it have some kind of crowbar to protect if the regulator shorts to the 12 volt input? It says 'patented protection circuit' or the like on the ebay site.

author: nukie
author_rank: Frequent Contributor
timestamp: August 22, 2013, 01:27:46 am
content: The first post got me interested in tearing apart my car usb adapter. I bought it because of the advertised 2A output and let me tell you that a few dollars means a big difference in quality. I guess if it can do 2A means it's not powered by the typical piss poor MC34063. So this post pushed me to the edge, I was never able to open it to confirm the truth, so today I performed some skillful dremeling to the appropriate spots and out come the circuit board.It is two piece, right angle T design, it makes sense it saves some space and to be able to fit two ports there. There's no fuse to start with. I love the one piece spring wing contacts, they are very well design, they are also the culprit that prevent from disassembly. It's interesting to see a toroid here instead of a common bobbin inductor.The two ports are connected to the same ground and positive, the difference is the 1A usb port ground is connected to a 0.1ohm (R11) resistor as a current limiter. So the two ports share current. The data lines are well implemented with appropriate resistors for those devices which are anal(Apple) with the holes they plug into.The main IC responsible is YF1220 step down converter. A bit of googling got me the chinese chip along with poorly written datasheet. According to the website this chip is designed for car usb charging. It's switching max current limit is 3A. With the USBs PCB board removed, the standby current is 1.6mA and with it attached is 4.1mA. This is inline with the datasheet where the quiescent current 1-2mA. The output is set to 5.2V which is great for long cables that causes voltage drop.http://www.universe-micro.com/open_pro.php?id=211www.universe-micro.com/upload/8341717048507.pdf

author: dexters_lab
author_rank: Unknown
timestamp: August 22, 2013, 06:17:13 am
content: Yea, that looks the same as mine, though i see you did have to butcher it to get the pcb out!Thanks for sharing!

author: jh15
author_rank: Frequent Contributor
timestamp: August 27, 2013, 04:50:16 am
content: Just got 2 from the ebay link. Mine says YIBOYUAN on it. going to test with my Nook color and Samsung Galaxy note 2.Hope they put out a tad over 5v.still worried about a short to 12v.