---- START NEW MESSAGE --- Received: from cherry.ease.lsoft.com [209.119.0.109] by dpmail10.doteasy.com with ESMTP (SMTPD32-8.05) id AB09248A006A; Sat, 31 Jan 2004 08:42:49 -0800 Received: from PEAR.EASE.LSOFT.COM (209.119.0.19) by cherry.ease.lsoft.com (LSMTP for Digital Unix v1.1b) with SMTP id <17.00CC68E3@cherry.ease.lsoft.com>; Sat, 31 Jan 2004 11:42:36 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8e) with spool id 9039 for PICLIST@MITVMA.MIT.EDU; Sat, 31 Jan 2004 11:42:31 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 1379; Sat, 31 Jan 2004 11:40:42 -0500 Received: from bay8-dav5.bay8.hotmail.com [64.4.26.109] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with ESMTP ; Sat, 31 Jan 2004 11:40:41 EST X-Warning: mitvma.mit.edu: Host bay8-dav5.bay8.hotmail.com claimed to be hotmail.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sat, 31 Jan 2004 08:40:43 -0800 Received: from 67.65.155.200 by bay8-dav5.bay8.hotmail.com with DAV; Sat, 31 Jan 2004 16:40:43 +0000 X-Originating-IP: [67.65.155.200] X-Originating-Email: [jsears2027@hotmail.com] X-Sender: jsears2027@hotmail.com References: <20040131075611.GA71948@saturn.home.ben.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 X-OriginalArrivalTime: 31 Jan 2004 16:40:43.0851 (UTC) FILETIME=[F84311B0:01C3E818] Message-ID: Date: Sat, 31 Jan 2004 10:40:35 -0600 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: James Nick Sears Subject: Re: [PIC:] 16LF877A A/D To: PICLIST@MITVMA.MIT.EDU Precedence: list X-RCPT-TO: Status: U X-UIDL: 371856683 ----- Original Message ----- From: "Ben Jackson" To: Sent: Saturday, January 31, 2004 1:56 AM Subject: Re: [PICLIST] [PIC:] 16LF877A A/D > You should use the right Fosc. Don't use one that's "conservative" and > don't use the RC option unless you sleep during conversion (it says so > right beneath the table, but I managed to misinterpret that myself > several times). So you are saying that performance is better when you are close to (but of course not under) Tad = 1.6us? Actually after doing a little more datasheet hunting, the 16LF877A has a rated minimum of 3.0us. Are you sure? I have no grounds to argue but it just seems counter-intuitive to me, especially since I can't find any mention of such an effect in the docs. I do remember (although I can't remember if it is in the datasheet or in the mid-range manual) seeing that you should NEVER use the RC mode without sleeping through the conversions. > I was just experimenting with that last night and it > definitely makes a difference. I'm talking about losing a few bits of > resolution, not half scale deflection, though. Do you have any more details of what the effects were w.r.t. Tad. From what I can see in the datasheet, in theory anyway, the performance should not decline with a longer Tad so I am curious. Thanks for the info Nick -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu .