Diode (or MOSFET) and supercap? On 10/18/2018 6:04 AM, David Duffy (AVD) wrote: > Customer specification. Not my call. > David... > > On 18/10/2018 7:39 PM, AB Pearce - UKRI STFC wrote: >> Why don't you want Li cells? >> >> >> -----Original Message----- >> From: piclist-bounces@mit.edu On Behalf Of Dav= id Duffy (AVD) >> Sent: 18 October 2018 10:24 >> To: Microcontroller discussion list - Public. >> Subject: Re: [EE] 5V UPS >> >> Yeah, I've seen a few but so far they are all lithium cell based. >> David... >> >> On 18/10/2018 6:45 PM, AB Pearce - UKRI STFC wrote: >>> There are "UPS" devices around for use with raspberry Pi. The one I rec= all seeing is done as a HAT board. Maybe something like this could be adapt= ed to your usage. >>> >>> >>> >>> -----Original Message----- >>> From: piclist-bounces@mit.edu On Behalf Of >>> David Duffy (AVD) >>> Sent: 18 October 2018 05:08 >>> To: PicList >>> Subject: [EE] 5V UPS >>> >>> I have a need for a "5V UPS" for want of a better term. >>> >>> Input from the mains power source is 5V and limited to around 150mA . O= utput to the system is 5V, 90mA at idle with short bursts of up to 500mA re= quired. >>> >>> Battery capacity required is somewhere in the 1AH - 2AH range. Battery = can not be Lithium based. Options are Ni-Mh or SLA or ??? >>> >>> Mains will normally be available 24/7, but if it fails I need to keep r= unning from battery until it reaches its safe low voltage point. >>> >>> Any pointers on the best battery chemistry to go with and what type of = charging will keep it healthy long term? >>> David... >>> --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .