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launchpad msp430f5529 5v external power supply

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hi, i'm a proud owner of a launchpad Msp430F5529, 

and i'm trying to power it up with an external 5v power supply. 


if i connect the device to my computer - it works.

i connect the 5v network it doesn't work.

i connect the 3v3 network to a 3v3 power supply - it works.

i connect the launchpad to a galaxy cell-phone charger - still , no work. 


the 5v , 3v3 ang GND jumpers are connected. when i connect the 5v power supply i measured the voltage on the 3v3 jumper - nothing there. 

i assume the computer is activating the dc-dc convertor which is not powered when no computer connection exits , if thats the case , how can i work it to work ? 

if i'm wrong, what is the problem? 

thank you



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According to http://43oh.com/2013/09/msp430f2559-launchpad-first-impressions/ you can't. TI has a faq that says it's because powering the usb devices before the usb hub is powered up is bad. If you ever had a cheap Chinese usb hub you know that's not reality.


The usb hub controls a pair of usb power switches. If the hub doesn't enumerate, the switches aren't enabled. Instead of adding a jumper or a switch or something, TI forces you to use an external 5 and/or 3.6 supply.


You can fix this with some soldering, I'll look at the schematic when I can

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i have the Rev 1.4 . 

the usb power supply is not such an issue for me,   but the external power supply using the pins is. 

if i connect a 3v3 + GND to the 3v3 network my device works just fine , but if i supply 5v directly to the 5v pin - nothing happens, the dc-dc doesn't either gets power (which is odd, there is power in the 5v jumper) , or it does get power but doesn't convert (the 3v3 jumper isn't getting power). 


if i could either connect the device directly to a 5v or insert a 5v supply through USB both will be Okay (preferably directly to the pins). does that require soldering as well?

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