Skip to content

  • Projects
  • Groups
  • Snippets
  • Help
    • Loading...
  • Sign in
F
FMC MasterFIP
  • Project
    • Project
    • Details
    • Activity
    • Cycle Analytics
  • Issues 1
    • Issues 1
    • List
    • Board
    • Labels
    • Milestones
  • Merge Requests 0
    • Merge Requests 0
  • Wiki
    • Wiki
  • image/svg+xml
    Discourse
    • Discourse
  • Members
    • Members
  • Collapse sidebar
  • Activity
  • Create a new issue
  • Issue Boards
  • Projects
  • FMC MasterFIP
  • Issues
  • #34

Closed
Open
Opened Mar 26, 2015 by Projects@orson_admin
  • Report abuse
  • New issue
Report abuse New issue

-5V regulator shutdown pin pulled-low

The -5V regulator LT1931AES5#PBF (IC13) shutdown pin is currently pulled low with a 30k resistor.
This pin is active low. To enable the regulator, a voltage bigger than 2.4V must be applied (LT1931 datasheet).

It might not work as the FPGA Vohmin with VADJ=2.5V can be as low as 1.9V in the worse case.
See Spartan-6 FPGA Data Sheet: DC and Switching Characteristics pages 8 and 10.

The shutdown pin should be pulled high to +12V instead. As for the 1V8 regulator LT1763IDE-1.8#PBF (IC9).

Assignee
Assign to
None
Milestone
None
Assign milestone
Time tracking
None
Due date
No due date
1
Labels
bug
Assign labels
  • View project labels
Reference: project/fmc-masterfip#34