In SX Microcontrollers, SX/B Compiler and SX-Key Tool, George Herzog wrote:

I just got several SX28 Proto boards and wanted to track down the power with a VOM.
 

I plugged one in without any crystal or devices connected to the board and got a reading of over 7 volts DC.  My input voltage is a wall wart that reads about 14.78 volts DC, though it is rated lower [12 or 9 volts, I have to crawl under the desk to actually see].

 

The LM2940-5.0 is rated at 26volts absolute Max in its PDF.  So I didn't think there was reason to worry.

I do see that board say 6-9VDC.  And the output side regulation capacitor seems small [should be 22.5uf or larger according to my PDF].

 

Is this a defective board or did I miss something?  As it stands, the SX28 is rated at 7volts max, so I fear damage.

---------- End of Message ----------


You can view the post on-line at:
http://forums.parallax.com/forums/default.aspx?f=7&p=1&m=161172

Need assistance? Send an email to the Forum Administrator at forumadmin@parallax.com

The Parallax Forums are powered by dotNetBB Forums, copyright 2002-2006 (http://www.dotNetBB.com)