Just had my first frying pan SMD desoldering adventure!
Turns out the microcontroller didn't get zapped at all, it was the flash chip dragging down the MISO line after being fried. Turns out 15v should not go anywhere near your 4v power rail.
[editline]22nd August 2014[/editline]
[img]http://i.imgur.com/6cY4G7w.png[/img]
The Extech says 1.01 Amps. Given this is pre-calibration, I am pretty happy!
It's measured around 1.6A continuous for 30 seconds, the shunt resistor didn't feel warm at all.
[QUOTE=gamerpaddy;45762059]they are pretty cheap. 5.50€ per led, 3€ per stepup or 5€ for stepup with constant current
8€ per lens and heatsink from junkyard[/QUOTE]
Where did you get your lenses and whats the focal length?
[QUOTE=Cakebatyr;45763008]Where did you get your lenses and whats the focal length?[/QUOTE]
[url]http://www.ebay.de/itm/380630845376[/url] bought mine a half year ago, the price increased a bit
Since everyone was playing with high powered LEDs here, I thought I'd also give this whole thing a shot, although my approach was a little bit different:
[t]http://i.imgur.com/g6z9lAV.jpg[/t]
More:
[url]http://imgur.com/a/IZVbM[/url]
[T]http://i.imgur.com/nWGXVk6h.jpg[/t]
Guess who wasn't paying attention when adding a switch to my digikey order!
How the hell did you accomplish that?
[QUOTE=pentium;45770267]How the hell did you accomplish that?[/QUOTE]
See a switch, don't pay attention, click "add to cart". I have a bag of 12V super-bright blue LED switches from doing the exact same thing.
I am either really missing something or Lattice is just significantly cheaper for low end parts at least, than Altera and Xilinx. After having synthesised my design targeting both a Cyclone 2 and a MachXO2 part, they come out with similar utilizations on both, means I can easily fit into the fairly inexpensive 640 LUT Lattice parts which is great. Still wish there was somewhere I could get the MachXO2 breakout board over here though, instead of having to get a Mouser order over £50.
[QUOTE=Fuxed;45772411]See a switch, don't pay attention, click "add to cart". I have a bag of 12V super-bright blue LED switches from doing the exact same thing.[/QUOTE]
On my local web shop it randomly adds items into your cart and you have to pay attention so they don't send you some bullshit.
I don't know why it does this but I suspect they do it on purpose :v:
[QUOTE=Fourier;45777290]On my local web shop it randomly adds items into your cart and you have to pay attention so they don't send you some bullshit.
I don't know why it does this but I suspect they do it on purpose :v:[/QUOTE]
I did this with Scan once, accidentally ordered a case for a long since dead PDA with the parts for my computer.
Couldn't sleep last night so I disassembled an old dvd drive whilst listening to some smooth jazz.
Got myself a couple of [wavelength unknown] laser diodes (just need to make a driver circuit to test 'em out), and found some neodymium magnets so strong I can't separate them from eachother :v:
green laser diodes? From dvd drive?
Wat
green laser diodes are expensive and still in development. For green light, they use a infrared diode and Neodymium crystal to "double" the wavelength. cd drives use infrared diodes, dvd drives red ones, bluray using 405nm diodes (violet)
Ah right, they're probably red then. Unfortunately there's no official spec for the optical drive online that I could find, so I was going by an old post on the laser pointer forums.. I'll find out when I test them I guess.
[QUOTE=gamerpaddy;45777448]green laser diodes? From dvd drive?
Wat
green laser diodes are expensive and still in development. For green light, they use a infrared diode and Neodymium crystal to "double" the wavelength. cd drives use infrared diodes, dvd drives red ones, bluray using 405nm diodes (violet)[/QUOTE]
Not to mention that a good number of green lasers (that I've looked at) lack a filter for the infrared potion that leaks through.
Also optical notch filters are really expensive.
[editline]23rd August 2014[/editline]
Can I nominate Wiznet for having terrible pin design?
[url]http://www.wiznet.co.kr/sub_modules/en/product/Product_Detail.asp?cate1=5&cate2=42&cate3=0&pid=1026[/url]
40 pins in 2*2x10 configuration and you only need six of them for SPI to work. The rest are already on the board.
Hey guys I'm having trouble sourcing this part: [url]http://www.pixart.com.tw/product_data.asp?product_id=100&productclassify_id=1&productclassify2_id=2[/url] It's an ADNS-3530 wireless mouse sensor. I need it for a project.
A few years ago you could order from DigiKey etc. but ever since Avago has sold their mouse technology to Pixart they aren't available anymore. :(
Does anyone have any experience ordering similar parts? Especially from Alibaba/Aliexpress since it seems they're the only option aside from eBay.
Why does this 220V to 5V usb sounds like "gasmask"? Like this:
almost silence 6 seconds.....half second "shhhhhhhh".....almost silence 6 seconds.....half second "shhhhhhh"...
I guess it has big capacitor, which gets filled up fast then it draws energy slowly from this capacitor..
Sounds more like a poorly designed buck converter, poor filtering that may result in audible line noise?
Does it make that sound under load?
my mom's Asus transformer tablet apparently only charges if it's plugged into a USB 3 plug or if you use the original charger that came with it. otherwise, nothing will happen if you plug it in. figure maybe it's a power/amperage draw problem but I don't think usb3 standards have changed rated current, right?
)
Anyone have any ideas? (maybe this is more of an Android problem...)
USB 3.0 can give up to 900 mA, while 2.0 can usually only output 500 (later versions allowed for more, but Android limits draw to 500mA) When plugged into a 2.0, go into the battery settings, does it say that it's charging?
[QUOTE=Gulen;45795115]USB 3.0 can give up to 900 mA, while 2.0 can usually only output 500 (later versions allowed for more, but Android limits draw to 500mA) When plugged into a 2.0, go into the battery settings, does it say that it's charging?[/QUOTE]
Not entirely true, there's also a charging standard for USB 2.0 which allows for more current draw, up to 2 amps ish
Tablets charge on a 5V 2.1 or 2A outlet. Some will charge on a 0.5A plug but only when the screen is off.
But I know what you mean, my dad's Asus ultrabook doesn't charge on Belkin USB outlets with identical ampere ratings.
[QUOTE=metallics;45795565]Not entirely true, there's also a charging standard for USB 2.0 which allows for more current draw, up to 2 amps ish[/QUOTE]
Yes, but android limits itself to .5A on a USB connection, even if the standard was changed (like I pointed out)
Also I downloaded the freeware version of EAGLE, wow this is so much easier to get into than KiCAD.
RasPi stepper motor drive here I come.
[QUOTE=Cakebatyr;45795728]Tablets charge on a 5V 2.1 or 2A outlet. Some will charge on a 0.5A plug but only when the screen is off.
But I know what you mean, my dad's Asus ultrabook doesn't charge on Belkin USB outlets with identical ampere ratings.[/QUOTE]
That's because your tablet doesn't identify the outlet as a proper charger (because most chargers aren't made with the connection between data+ and data- which tells Android it's a charger)
[QUOTE=LoneWolf_Recon;45794524]Sounds more like a poorly designed buck converter, poor filtering that may result in audible line noise?
Does it make that sound under load?[/QUOTE]
Yes, only under load.
[editline]26th August 2014[/editline]
[QUOTE=Gulen;45795762]That's because your tablet doesn't identify the outlet as a proper charger (because most chargers aren't made with the connection between data+ and data- which tells Android it's a charger)[/QUOTE]
That is bollocks, why don't they just accept the 5V volt line at whatever amperage there is? After all, it will only charge at slower rate.
[QUOTE=Gulen;45795762]That's because your tablet doesn't identify the outlet as a proper charger (because most chargers aren't made with the connection between data+ and data- which tells Android it's a charger)[/QUOTE]
IIRC what they usually have is a potential divider circuit biasing each of the data pins which is what apple devices look for, whereas android devices look for a short.
[editline]26th August 2014[/editline]
[QUOTE=Fourier;45804175]Yes, only under load.
[editline]26th August 2014[/editline]
That is bollocks, why don't they just accept the 5V volt line at whatever amperage there is? After all, it will only charge at slower rate.[/QUOTE]
Because standards and acceptable current limits from data ports are different than from charging ports. If it just drew all the current it could you'd probably end up blowing fuses in the USB of things like computers.
[QUOTE=metallics;45805429]IIRC what they usually have is a potential divider circuit biasing each of the data pins which is what apple devices look for, whereas android devices look for a short.
[/QUOTE]
Apple uses a certain voltage on the data pins (2.8V on D+, 2.0V on D-), and Android looks for a short, or a 200ohm resistance between D+ and D-, as per the EU-spec. You can make a charger do both, [URL="http://blog.curioussystem.com/2010/08/the-dirty-truth-about-usb-device-charging/"]detailed blog post on the topic[/URL]
Does anyone here own a BeagleBone Black?
I'm looking for a faster way to access SPI (not via /dev/spidev*) but there are no mmap libs out yet (as far as I am aware).
For the RPi there is [url=http://www.airspayce.com/mikem/bcm2835/]this lib[/url] so I thought similar ways could be used to write to SPI via mmap on the BBB.
Where could I get information on howto access the SPI master?
[QUOTE=LuaStoned;45815295]Does anyone here own a BeagleBone Black?
I'm looking for a faster way to access SPI (not via /dev/spidev*) but there are no mmap libs out yet (as far as I am aware).
For the RPi there is [url=http://www.airspayce.com/mikem/bcm2835/]this lib[/url] so I thought similar ways could be used to write to SPI via mmap on the BBB.
Where could I get information on howto access the SPI master?[/QUOTE]
If you can get ahold of register maps (datasheet?) you could probably directly drive the spi registers.
[QUOTE=LuaStoned;45815295]Does anyone here own a BeagleBone Black?
I'm looking for a faster way to access SPI (not via /dev/spidev*) but there are no mmap libs out yet (as far as I am aware).
For the RPi there is [url=http://www.airspayce.com/mikem/bcm2835/]this lib[/url] so I thought similar ways could be used to write to SPI via mmap on the BBB.
Where could I get information on howto access the SPI master?[/QUOTE]
A friend of mine has had minor success with the [URL="http://en.gnublin.org/index.php/Tutorial_API_BeagleBoneBlack"]Gnublin[/URL] library for BeagleBone Black.
Sorry, you need to Log In to post a reply to this thread.
