IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...

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Hi Brum
Glad you had success.

I have done this and power with 3v3 but from LT1963. I dont have a battery supply. I am all linear regs.

I realise I probably have left a lot of performance on the table. Ian is out of battery psus but I am not sure I am really wanting to go that route.
Supercaps also interest me but I'm not keen on the little bombs sat in my living room in case of a short!
 
Hi Brum
Glad you had success.

I have done this and power with 3v3 but from LT1963. I dont have a battery supply. I am all linear regs.

I realise I probably have left a lot of performance on the table. Ian is out of battery psus but I am not sure I am really wanting to go that route.
Supercaps also interest me but I'm not keen on the little bombs sat in my living room in case of a short!

It is certainly more convenient to not use batteries! I have one 3.3v battery that I switch on and off using one of Ian's basic relay boards from a previous GB. Based on only needing one 3.3v battery, I think I will stay with this arrangement, rather than buying the battery management board.
 
I've bypassed the LDO's this morning and as reported by Greg and others, it makes a large improvement when powering the FifoPi with a 3.3v battery.

Just to make it clear. (for myself). Ian says that it is theoretically best to bypass the regs with a jumper, but if it’s feeded with 3.3v, this will be done automatically. So is theory and practice the same here ? Or ?..

Anyone tried both options ?
 
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So if I understand this whole thing.....provide the caps 3v3 to charge. How do I know they are charged? DVM I assume and measure the time it takes for future charges...that way I dont have to dvm test on subsequent charges.?
Do I have them connected to the dac during charging? If out of circuit for charging....on connecting up I guess there quite a spark....I assume this is where the finesse of Ian's psu has been aimed.?
 
I would charge with it disconnected from DAC, then connect after reaches 3.3 or whatever target voltage is.

The thing I've noticed is the reg can get really hot when charging a big ultracap. I have a fan for when I charge the caps, helps keep it reasonably cool.

You can connect a charged cap to a circuit, but have to be really careful. I have been using two posts and a little jumper to make a simple switch. After cap is charged, I install the jumper to connect cap to load.

BTW, in your ebay link, I'd be worried about all the parts on the circuit card, and what they do. Make sure they don't mess up the ultracap "goodness". You really don't want anything be wire between cap and load. My simple switch is a compromise for usability.