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From: Electron Subject: RE: [EE] Solution for slow Vcc rising on PIC321xx In-Reply-To: <68C48B7730F8B04F8230C4E33C4354DC2673CE0D@EXCHMBX01.fed.ccl rc.ac.uk> References: <201204141008.q3EA8PiP031028@mailhub-dmz-2.mit.edu> <68C48B7730F8B04F8230C4E33C4354DC2673CE0D@EXCHMBX01.fed.cclrc.ac.uk> Mime-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpmleJIrShJLcpLzFFi42IJjDCw0FWf0ulvcGePtsW3c4+YHRg9ms4c ZQ5gjOKySUnNySxLLdK3S+DK+L/+KHvBPe6KM50tzA2M6zi7GDk5JARMJG7e+M8OYjMKGEns PveKFSIuJnHh3nq2LkYuDiGBy4wSr+bNZgRJCAl4SNw9tpINwp7NKNGz2rKLkQOowVBi+wIW kDCLgKrElQ1vmUBsEQFHieWNy8FsNgENiSsb14HtEhawkpgw+wHYSE6BEIneY0+hdrUxSqw5 08cMMpNXQFDi7w5hkBpmAR2JBbs/sU1g5J+FkJmFJLOAkWkVo2xKbpVubmJmTnFqsm5xcmJe XmqRrpFebmaJXmpK6SZGYHgJcUry7mB8d1DpEKMAB6MSD6+QWYe/EGtiWXFl7iFGSQ4mJVHe wImd/kJ8SfkplRmJxRnxRaU5qcWHGCU4mJVEeAt7gXK8KYmVValF+TApaQ4WJXFeVa13fkIC 6YklqdmpqQWpRTBZJg72Q4wyHBxKEryFk4G6BYtS01Mr0jJzSpDVcIIILpA1PEBrNkwCWVNc kJhbnJkOUXSK0ZjjcMuxK4wcE6+dusIoxJKXn5cqJc5bCzJTAKQ0ozQPbiQsbVxilJUS5mVk YGAQ4gG6CRgUqPKvGMWBwSDMmwoyhSczrwRu3yugU5iATuFTaAM5pSQRISXVwChu0JOSwvfD 7fqlhL/l9hsbnmbHm0y5G+rCl7b0ZtFpkwW3/9zewTJti6t4JzPL2QkMxktWJ57WyTj+OmTj JXH57pr7pRUs+g2lm25K8zLPvZ9ovqSSJ/lZ766z21eUiCYaWzhrZmfFnnDlrZ0fyc4V/1Dq 4vNXK7dvePM+3saa/4SAy4qleUosxRmJhlrMRcWJAFEd36sWAwAA X-Topics: [EE] X-BeenThere: piclist@mit.edu X-Mailman-Version: 2.1.6 Precedence: list Reply-To: "Microcontroller discussion list - Public." 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List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: piclist-bounces@mit.edu Errors-To: piclist-bounces@mit.edu At 15.57 2012.04.14, you wrote: >> After research, my best candidate is to replace the Vreg from the >> actual LP2950 to a LP2951, and connect its ~ERROR output to MCLR, >> possibly directly (to save components). >> >> What do you think about my solution? :o >> >> >Hello folks, >> > >> >I have a PIC321xx application where I cannot ensure that Vcc rises >> fast enough. >> > >> >The net effect, coming without surprise, is that sometimes the MPU >> >doesn't start at all (not even the LPRC Timer starts, or at least >> >I'm sure that enabling the WatchDog didn't help), unless I manually >> >reset >> it. >> > >> >How would you automatize this with the least possible number of >> >cheapest possible components? >> > >> >Or, can you suggest a cheap <500mV@100mA LDO voltage regulator with >> >reset management (or equivalent "power good" feature) capable of at >> >least 100mA at 3.3V fixed voltage output, and a voltage input of at >> least 30V? > >Does the processor not have a brownout function? Yes, and it doesn't really seem to help.. not in slow rising Vcc, which is in the datasheet (the requirement), so BOR or not BOR, to handle it properly is actually a requirement. >I haven't had anything to do with PIC32 chips, so haven't had occasion >to look at these aspects. > > >-- >Scanned by iCritical. > >-- >http://www.piclist.com PIC/SX FAQ & list archive View/change your >membership options at http://mailman.mit.edu/mailman/listinfo/piclist