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Topic: EEPROM better than SD card for audio ? (Read 3051 times) previous topic - next topic

Boffin1

Theres a reference here to the regulator Crossroads is using, 400mA  and 700mV dropout.

I am using the LD33V  TO220 package with 800mA output, I have plenty of room for it on the board.


http://www.infineon.com/dgdl/Industrial-Standard-Pocket-Guide-2011-04.pdf?folderId=db3a30431be39b97011c1dfc76d7781d&fileId=db3a30432d9b3066012da32dcb5b3561

Boffin1

I had one of my 4 working SD cards pack up before I added the delay to the triggering micro,  but the card could still be read by the PC, so I reformatted it with SDformat, reloaded the wav files and it works OK again.

I have since added a 2 second delay on the triggering micro ( though I cant see why it should cause intermittent problems ) and they are still all working.

I am not sure that this is going to be reliable, so I will have another go at the eeprom, and perhaps make 2 plug in audio cards to choose from.....

CrossRoads

I think this is the regulator
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=IFX25001ME%20V33INCT-ND
I had to work thru the digikey filtering to find it, a search for IXF25001 wouldn't bring it up.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

CrossRoads

Also, that regulator was kind of an choice by necessity - a previous board design was already done, and we realized the regulator selected didn't have enough current capability, so I had to scramble to find one with more current capability but still had to meet the existing footprint.
When I did the Bobuino, I then used that same part, seems to provide all the current needed for the 1 SD card I have to test with, a 16 GB Sandisk Ultra 15 MB/S card.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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