What purpose of Vcap pin Pic24FJ

talamahahahe · Joined: 15 Feb 2015 Posts: 39

i see pin Vcap in PIC24 but i don't know it 's use for what ??? and how much capatitor' value should use ??

Kind Regards,

mbradley · Joined: 11 Jul 2009 Posts: 118 Location: California, USA

External filter cap, used for internal regulator.

It's is very important to check the data sheet for the specific chip you are using. When I use a pic, it is 100% absolute that I have the data sheet for it, so I know what all the pins do, what they can do, how I can power it, etc....
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Michael Bradley
www.mculabs.com
Open Drivers and Projects

Ttelmah · Joined: 11 Mar 2010 Posts: 19539

Very true.

Data sheet, and reference manuals for each peripheral you use.

In the case of Vcap, if you look at a typical chip like the PIC24FJ128GA310, you have an entire manual _section_ for this, telling you what type of capacitor (ceramic or tantalum - beware of tantalum if this is a high reliability device, unless you use MIL spec wet tantalum), and even giving specific capacitors that are suitable.

guy · Joined: 21 Oct 2005 Posts: 297

Agree. This is the difference between a system that works sometimes and a system that works always...