dc-dc Buck vs boost efficiency
Hi guys.
When you use solar panels and have gadgets with different voltage requirements that you want to power up.
I need atleast 2 different outputs, 5v and 12v ,
so which is most efficient , 12/15v panels that you regulate to 5v , or 5v panels boosted to 12v?
is there any general advantage in either case
and i,m talking about using cheap ebay switch regulators / boost converters, not anything expensive hi tech.
regards
Discussions
5 years ago
In general buck supplies are more efficient than boost, but Ebay crap isn't likely to push the envelope, because they'll use cheap parts, and particularly the inductors will be badly made.
Reply 5 years ago
Ok,that suprised me, i always have thought the opposite
prob cause i tend to think regulating downwards always has to dissipate power into heat
Reply 5 years ago
....and regulating upwards gets the energy from where...
No, the higher available voltage improves switching in the power devices, and reduces the switch current
5 years ago
Trying to boost a 5V panel to 12V may be an issue since you sacrifice amperage for voltage. If the panel can't supply enough amperage then you won't be able to boost it to 12V. So start with a 12V panel and regulate it down to 5V. You can use a decent switching regulator rather than your typical 7805 so you don't loose as much efficiency.
It would be best if you use the panel to charge a battery then run your regulator or boost off the battery to your devices.