Power Backup by Super capacitor

[MMARI.1]

 

 

 

 

hi ,

Aiming to have few minutes power  back up for  STM32 mcu with SD card incase main supply 5v goes OFF condition . Timer added for capacitor  charging time since initial current is will be little high .

The above is setup enough ? or something special circuit to be build for super capacitor ?

 

 

[MHoll.2]

Normally this Supercap's have rather high ESR, so probably not a good idea. If You really need some minutes of backup you will need to do this with a battery, If you need only some 100's of ms then I would use some "normal" Capacitor, but be award that the STMPS2151 will only work down to about Vout + 0.5V.

[MMARI.1]

hi,

can you suggest 3.7v battery charger + battery switch  over  to main supply handling  IC number ?.