Jump to content
43oh

launchpad msp430f5529 5v external power supply


Recommended Posts

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

 

 

Link to post
Share on other sites

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

Link to post
Share on other sites

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?

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...