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controller hang while SD card WRITE operation

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tongbram

New Member
hi i m doing a SD card based GPS data logger. I have completed almost every thing, what i m facing problem is that my controller(18F2550) hang in the write operation and it is because of noisy power supply. My project run fine on table top but when i tested on noisy power supply on vehicle(OLD FAIT CAR BATTERY) it hang in the middle of write operation.
i have did all the way to reduce noise. i m using 0.1u, 1000uF polar and 8.2uH inductor for SD card power filter but no luck. along with all the necessary decoupling cap for controller supply. can anybody have any idea on this??????????
 

UTMonkey

New Member
I am pretty much a self professed noob in electronics but one of the things I came unstuck with in my SD project was that the 3.3 regulator i used could only supply 100mA.

According to some datasheets some SPI read and writes can take 150-200mA.

Just a thought.

Mark
 

tongbram

New Member
thanks for ur reply.......basiclly for 3.3V supply i m using LM317 which has 1.5A output currrent.
I m confused it is because of very very noisy power supply which i m using or because of the suppy noise on the SD card interfacing line. Can u suggest how can i reduce this supply noise......
 

Chippie

Member
thanks for ur reply.......basiclly for 3.3V supply i m using LM317 which has 1.5A output currrent.
I m confused it is because of very very noisy power supply which i m using or because of the suppy noise on the SD card interfacing line. Can u suggest how can i reduce this supply noise......
Better filtering of the supply....
Have you scoped the supply line to see what the noise looks like?
If you have poor filtering around the 317 it could be the source of the noise...
 

AtomSoft

Well-Known Member
Heh i am surprised no one said this but to get real help post:

1.Code
2.Schematic

This way we can see what you are doing and whats going on.
 
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