#qi-hardware IRC log for Monday, 2013-08-12

qi-bot[commit] Maarten ter Huurne: Renamed section left/right images (packages) http://qi-hw.com/p/gmenu2x/02dd54204:27
qi-bot[commit] Maarten ter Huurne: Made Link/LinkApp::searchIcon() protected (instead of public) (packages) http://qi-hw.com/p/gmenu2x/0d0eebe04:27
qi-bot[commit] Maarten ter Huurne: Minor cleanups in Menu::linkUp/Down() and setLinkIndex() (packages) http://qi-hw.com/p/gmenu2x/6cdd56904:27
qi-bot[commit] Maarten ter Huurne: Scroll when link cursor moves into top/bottom row (packages) http://qi-hw.com/p/gmenu2x/f820bf804:27
whitequarkhi folks17:21
whitequarkcan someone help us (me and my coworker)? wpwrak, DocScrutinizer05?17:21
whitequarkso we have this board with a boost converter... http://imgur.com/ytojaUl. The only things ever soldered are IC1, C1, L1, C2, R1, R217:23
whitequark(and the battery)17:23
whitequarkfor about half a hour the whole contraption eats 1mA and dutifully outputs 3V317:24
whitequarkafter that it starts to draw about 7A of current and explodes17:25
whitequarkthe schematics, component values and layout are copied from the datasheet verbatim17:25
whitequarkthe L1 has lower current rating, but is otherwise the same as the recommended component.17:26
whitequarkwhy the hell does it explode?!17:26
larsctimebomb17:31
larschave you messured the temperature17:32
wpwrakthose russian terrorists again ...17:32
whitequarklarsc: well, it cannot possibly heat up while consuming 1mA@1.5V17:33
whitequark(and it doesn't)17:33
pcercueisome component burns, and creates a short circuit?17:33
larscread one 1A, sorry17:33
larscs/one//17:34
whitequarkpcercuei: nope, just the IC itself17:35
whitequarkand it's not like it can burn: again, 1mA idle17:35
pcercueiok17:35
larscso the datasheet claims it has a different pinout17:37
whitequarklarsc: oh?17:38
larsctps61220, right?17:38
whitequarkyes17:38
larsclooks different, although it is kind of strange that you should still get 3.3V17:39
whitequarklarsc: not sure I follow; I just compared and it's the same17:39
whitequarkwhere does it differ ?17:41
larscah, the pins are just not in order in the schematic17:41
Action: whitequark nods17:42
whitequarkwell, so the current plan is to buy a bunch of chips from a different supplier (and hopefully different batch)17:42
whitequarkand ask TI why the hell does that happen17:43
larscin the end they are going to be fake ICs17:43
whitequarkfrom farnell ?17:44
larschm, maybe not17:45
whitequarkCountry of origin: US17:45
whitequarkso unlikely17:45
larscand it is a 20 not a 21?17:48
whitequarkyes.17:49
larscand you checked that all the pins are connected correctly on the pcb?17:50
whitequarkyes17:51
whitequark(and if not, why would it explode?)17:51
whitequarkI mean, I'm trying to imagine a failure mode where it would explode, and I wouldn't know how to cause that deliberately17:51
whitequarkit has over-current and over-voltage protection17:51
whitequarkover-temperature.17:52
whitequarkas you can see it has a diode between L and Vout17:55
whitequarkso if you just short Vout to ground, it will first shutdown and then explode17:55
larscI'd say it looks ok18:01
wpwrakwhat exactly explodes ? L1 ? IC1 ? both ?18:06
whitequarkIC118:06
wpwraknice :)18:06
whitequarkL1 heats up too, but not enough to explode18:07
wpwrakit's interesting that your battery would let something like that happen18:08
whitequarkAA batteries can provide quite a bit of transient current18:08
wpwrakmaybe try connecting a resistive load to see if it does that on its own or if the explosion is preceded by a load change18:11
wpwrak(resistive load) and remove/disconnect/halt the MCU and the display18:12
whitequarkwpwrak: oh, there's nothing except IC1 and associated passive components on the board at all18:12
wpwrakah, i see18:13
viricwpwrak: here some people say that Spain tries to force the british use the military18:56
viricto later they use the military against Catalonia18:57
viricsaying "the british were first"18:57
viriclet's see.18:57
wpwrakif the people get restless, start a war. what a novel idea ;-)19:28
viricpeace is only what comes after war.19:38
virica fleet of three british warships go to Gibraltar19:41
viricthe Spanish gov said that one spanish ship will go too19:41
viricwe will see how mad it gets19:42
larscviric: between wars19:43
viriclarsc: :)19:44
larscwait... Britain declared war on Spain?19:44
viriclarsc: I wanted to make the point on   "war -> peace -> degradation of peace -> war -> ..."19:45
viricbut I was only playing with words.19:46
larscI wonder what they are going to do when the military gets there19:52
pcercueiplay cards?19:52
viricspain being there, it will be ridiculous for sure19:52
viricI wonder if it will be as epic as the Perejil reconquest19:53
virichttps://en.wikipedia.org/wiki/Perejil_Island (incident of 2002)19:54
larscwhy do they even fight about a dead rock?19:55
viric:) interesting attitude, eh?19:55
viriclarsc: I guess we don't understand high politics19:57
larscyea19:58
viricthis isn't bad either: https://en.wikipedia.org/wiki/Peñón_de_Vélez_de_la_Gomera19:59
viric"In 1871, the Spanish Congress debated abandoning the peñón, since by that time it had lost its military interest, but in the end the proposal was dropped."19:59
larscI guess in the end its not really about the dead rock itself. And if there are frictions between the two parties, better this than fighting over a populated area20:09
viricbah, barely20:18
viricI bet the king of spain shares 'girls' with the king of morocco. They are good friends.20:18
viriclast week the king of spain went to Morocco to request indult to a big pedofile, and dozens of drugdealers20:19
viricand the other king agreed.20:20
wpwrakit's good to be above the law20:22
viricthere is a hit book nowadays, banned accross all country, about the royal family20:27
wpwrakheh, didn't know you were in malaysia ;-)20:29
viric:)20:31
larscwell, animal farm taught us that the pigs are more equal ;)20:50
viric:)20:55
wpwrakviric: http://www.youtube.com/watch?v=StJS51d1Fzg21:10
viricyes, that attitude.21:14
virichm the mayor of london got into the topic. Accuses spain of going back to Franco regime, and hopes that the fleet going to Gibraltar with 'elite troops' does not go there 'by chance'.21:25
--- Tue Aug 13 201300:00

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