I'd like to know if it's a good choice this buck-boost converter [TPS63061] for a portable device. The input voltage is going to be two 2-cell Li-Ion 8.4V and the output is going to be 3.5 Volts.
The normal power consumption it isn't going to be greater than 200mA, but occasionally I'm going to have to use 2A because I've got a GPRS in my system. In TX burst mode the GPRS has a power consumption of 2A. GPRS: The duty cycle of the GPRS is 11.12% [max 2A during 577 usec] and 88.88% [max 500mA. during 4.615msec].
Most of the time it will be all disabled, and the power consumption is going to be the minimum possible. I'm going to use ultra-low leakage load switch, the TPS22860, to avoid wasting energy and to disable the parts of the circuit we aren't going to use.
The only part of the system is going to be always on it's a microcontroller. But this microcontroller is going to be most of the time in sleep mode with a power consumption of 10uA.
According to the datasheet the Iq is around 60uA, so I hope to get at the maximum power consumption of 100uA using the buck-boost converter TPS63061.
What do you think about that?
Best regards.