Hi, wanted to ask officially - is it possible to replace battery with supercapacitor - in TPS65217C ?
I cannot use batery ( due to device liftime requirements), but 5V 4F battery would provide me with enough energy to shutdown and store all data ( I use barebone mode with SPI/MMC storage )
Some threads suggest it should be pretty simple:
http://e2e.ti.com/support/interface/industrial_interface/f/142/t/206970.aspx
> A TI employee said [1] "The battery charger should work fine with a
> supercap. You'll need to make sure the TS (battery temp sense) pin
> is at a proper voltage to allow charging. If the supercap does not
> have a temperature sensor, you can simply put a 10k resistor from TS
> to GND."
Then just configure pmic to charge to max voltage ( 4.25V ).
Well, I might also have to tweak voltage sense to allow charging empty capacitor. Maybe add side resistor/diode circuit to charge it to e.g. 2V - so it is recognizable as connected ?
One more question - how long will the PGOOD stay good when operating with battery - as you cannot easilly maintain 3.3V on LDO? Does it cut off at 3.3V level ? ( I am asking as documentation says that the chip works with battery from 2.7V )
Or maybe ( as I use Vac only) - connect supercap on Vusb ( with separate charging) ?
