All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2
Author Message
 Post subject: Re: PC won't start with Seagate HDD connected
PostPosted: July 13th, 2010, 12:52 
Offline

Joined: May 15th, 2010, 17:30
Posts: 66
Location: United States
New TVS devices are available from DigiKey, Mouser, Jameco, Allied, Newark, etc. If you do not replace the TVS your drive will be without transient voltage suppression. Not the end of the world as most power sections of the drive have some TV survivability and Voltage overhead margin. The general problem with drives that use the TVS protectors is the power supplies have to wide of a Power Good margin. This can hammer a TVS as a one shot or multiple power on hits. TVS come in many forms and classes. (i.e. Zener, MOV, diac, etc). The two supply voltages are 5 and 12 nominal. 5.7 for the 5 and 13.2 for the 12 would be a save limit. If there is much interest I could provide a schematic and part numbers for a Home brew external TVS to connect in-line with the Molex connector.

Also I have a top mark directory so if you provide zoom photo of the TVS i may be able to identify the exact part and supply "Real" part numbers.

_________________
HWHacker
Smiles


Top
 Profile  
 
 Post subject: Re: PC won't start with Seagate HDD connected
PostPosted: July 14th, 2010, 19:53 
Offline
User avatar

Joined: September 8th, 2009, 18:21
Posts: 15539
Location: Australia
Outside the USA you can buy replacement TVS diodes from Farnell.

Use an SMBJ12A or SMAJ5.0A for the 12V and 5V diodes, respectively.

For datasheets and marking codes, here are my scratchpad style notes:
http://www.users.on.net/~fzabkar/HDD/TVS_diodes.txt

Alternatively, a P6KE15A or P6KE6.8A diode will also work, but they are leaded devices, not surface mounted. They may also have a somewhat higher breakdown voltage. You can solder them directly to the drive's power connectors.

See these datasheets:
http://www.st.com/stonline/products/lit ... 8/p6ke.pdf
http://www.littelfuse.com/data/en/Data_ ... e_P6KE.pdf


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 113 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group