MCUmall EPROM BIOS Chip Burner Forum
MCUmall EPROM BIOS Chip Burner Forum
Home | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 MCUmall Forums
 Using The Enhanced/Dual power Willem Programmer
 How Burn 27c256 without 12.5V ?

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize:
UserName:
Password:
Format Mode:
Format: BoldItalicizedUnderlineStrikethrough Align LeftCenteredAlign Right Horizontal Rule Insert HyperlinkInsert EmailInsert Image Insert CodeInsert QuoteInsert List Spell Checker
   
Message:

* HTML is OFF
* Forum Code is ON
Smilies
Smile [:)] Big Smile [:D] Cool [8D] Blush [:I]
Tongue [:P] Evil [):] Wink [;)] Clown [:o)]
Black Eye [B)] Eight Ball [8] Frown [:(] Shy [8)]
Shocked [:0] Angry [:(!] Dead [xx(] Sleepy [|)]
Kisses [:X] Approve [^] Disapprove [V] Question [?]

   Insert an Image File
Check here to include your profile signature.
    

T O P I C    R E V I E W
vincentes2000 Posted - 12/09/2005 : 05:38:31
Hi

I have The Enhanced Willem Programmer, i want burn a eprom 27c256, this VPP is 12.5V, I can burn this chip with 12 V (normal VPP)? or i must modify my burner "Enhanced Willem Programmer"

Thank's

Vincent
2   L A T E S T    R E P L I E S    (Newest First)
DL Posted - 04/15/2006 : 08:36:08
Hi,
quote:
Originally posted by silver_surfer

yes you cn use 27c256 with 12 volts just fine. I do near eveyday.

You might want to read this post http://www.willem.org/cgi-bin/yabb2/YaBB.pl?num=1144884107 regarding reliability. Programming with out-of-spec VPP isn't as bad as not setting VCC correctly, but you shouldn't make the mistake of assuming that programming and verifying in your programmer is the same as programming the device reliably...

The amount of charge stored on the floating gate is affected by both the programming VCC (affects the number of electrons in the channel that can be deposited on the floating gate) and VPP (helps attract electrons from the channel).

If you program at low VPP and incorrect VCC (which most with Willem programmers do), you're affecting program margin and that can mean reduced reliability.

HTH,
Dennis
silver_surfer Posted - 12/09/2005 : 17:23:35
yes you cn use 27c256 with 12 volts just fine. I do near eveyday.

MCUmall EPROM BIOS Chip Burner Forum © Copyright 2003 - 2009 Mcumall Electronics Inc. Go To Top Of Page
Generated in 0.05 sec. Snitz Forums 2000