CCS C Software and Maintenance Offers
FAQFAQ   FAQForum Help   FAQOfficial CCS Support   SearchSearch  RegisterRegister 

ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

CCS does not monitor this forum on a regular basis.

Please do not post bug reports on this forum. Send them to support@ccsinfo.com

Any idea if Microchip will support 3.3V on MCUs?

 
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion
View previous topic :: View next topic  
Author Message
Pavel Kolinko



Joined: 15 Mar 2005
Posts: 10

View user's profile Send private message

Any idea if Microchip will support 3.3V on MCUs?
PostPosted: Fri Nov 04, 2005 10:23 pm     Reply with quote

Microchip dsPic supports 3.3V.

However I was wondering if anyone knows
whether Microchip has plans to support 3.3V in MCUs.

I looked for 3.3V MCUs on Microchip website, but it doesn't seem like they have any.

Thanks in advance for your help.
Pavel
newguy



Joined: 24 Jun 2004
Posts: 1903

View user's profile Send private message

PostPosted: Fri Nov 04, 2005 10:29 pm     Reply with quote

The LF processors are low voltage capable. Some are able to run as low as 2.0 V (I think). For example, the 18F452 runs at 4.2 - 5.0 V, while the 18LF452 will run down to something in the neighbourhood of 2 or 3 V. I'm too lazy to look up the exact specs - check microchip's website again.
Pavel Kolinko



Joined: 15 Mar 2005
Posts: 10

View user's profile Send private message

Thanks!
PostPosted: Fri Nov 04, 2005 11:19 pm     Reply with quote

Thanks!
I found the LF parts that I need.
MikeValencia



Joined: 04 Aug 2004
Posts: 238
Location: Chicago

View user's profile Send private message Send e-mail Yahoo Messenger

PostPosted: Sat Nov 05, 2005 6:25 am     Reply with quote

Pavel,

Just make sure that you have Brown-Out Reset DISABLED. Otherwise, you'll never get these things to run! I guess the feature is in there because these same 3.3V chips can still run at 5V.
MGP



Joined: 11 Sep 2003
Posts: 57

View user's profile Send private message

PostPosted: Sat Nov 05, 2005 12:29 pm     Reply with quote

You also may have problems with low voltage in-system programming since you can't do a bulk erase at Vdd less than 4.2V. You need to be able to do a bulk erase if you want to change fuse settings, since a bulk erase is the only way to erase the existing fuse settings.
kender



Joined: 09 Aug 2004
Posts: 768
Location: Silicon Valley

View user's profile Send private message Send e-mail Visit poster's website Yahoo Messenger

PostPosted: Sat Nov 05, 2005 3:15 pm     Reply with quote

MikeValencia wrote:
Just make sure that you have Brown-Out Reset DISABLED. Otherwise, you'll never get these things to run! I guess the feature is in there because these same 3.3V chips can still run at 5V.

Mike, does it mean that LF chios would need an external microcontroller superviser with a different brownout detect? I've never used LF myself, but I'm curious, because eventually I'll need to re-tool to 3.3V, becasue 5V programmable logic, in turn, is gradually becoming exticnt.
ckielstra



Joined: 18 Mar 2004
Posts: 3680
Location: The Netherlands

View user's profile Send private message

PostPosted: Sun Nov 06, 2005 5:22 pm     Reply with quote

kender wrote:
MikeValencia wrote:
Just make sure that you have Brown-Out Reset DISABLED. Otherwise, you'll never get these things to run! I guess the feature is in there because these same 3.3V chips can still run at 5V.

Mike, does it mean that LF chios would need an external microcontroller superviser with a different brownout detect? I've never used LF myself, but I'm curious, because eventually I'll need to re-tool to 3.3V, becasue 5V programmable logic, in turn, is gradually becoming exticnt.
It all depends on the PIC model you are using, some models only have a single fixed BOR voltage while other models have multiple preset voltages you can select from. For example the old PIC18LF458 has BOR voltages of 2.0V, 2.7V, 4.2V and 4.5V
Display posts from previous:   
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
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 vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group