I'm using the LTC3350 in a product. The product regulates power to different hardware, basically a I/O module for hardware. One output needs a UPS for data security purpose.

I don't understand the difference of the LTC3350 and LTC3351 completely. I know the LTC3351 is 'hot swappable', but what does this exactly mean? Does it mean you can disconnect the output load and connect again when the LTC3351 is in backup mode? Or does it mean you can disconnect and connect the input of the LTC3351? Because the latter you can do too with the LTC3350 as I understand from the datasheet..

My unit needs to be able to provide power to the load for about 15 seconds when power input is suddently disconnected, Load is drawning 1,5 A average @ 12 V. Is this possible with the LTC3350? And can you tell me the exact difference with the LTC3351?

The circuit of the UPS unit of the circuit is below.