> -----Original Message----- > From: piclist-bounces@MIT.EDU [mailto:piclist-bounces@MIT.EDU] On Behalf > Of Mark Rages > Sent: 23 March 2010 17:18 > To: Microcontroller discussion list - Public. > Subject: Re: [EE] Current Probe? > > On Tue, Mar 23, 2010 at 12:20 PM, Harold Hallikainen > wrote: > > A tech just came to me with a problem on a board. A PIC is TRYING to > drive > > a line to 3.3V, but it's only getting to 1.9V. So, something somewhere > is > > holding it down. Has anyone had any luck with Hall effect current probes > > in tracing where current is going on a board? What particular probe are > > you using? > > > > That's quite a bit of current. The PIC has output resistance of ~35 > ohms IIRC, so maybe 50 mA It depends on the particular PIC being used, but they are typically a lot weaker sourcing current with a 3v supply than 5v. The 12F617 I have been using recently shows an equivalent output resistance of ~150 Ohms at 25 degrees Celsius with a 3v supply and small currents (< 4.0mA), and somewhat more than double that at 125 degrees Celsius. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. ======================================================================= -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist