SPV1050 -- best way to switch input power between low impedance source (USB) and high impedance sources (Solar, RF, TEG)

[PMcDo.1]

In my application I want to be able to charge a low mAh battery using the SPV1050's built in battery charging functionality (in buck/boost mode), but I want the ability to switch the energy input from a high impedance source (such as Solar), over to USB when I plug my device into my computer. My plan was to add some sort of power OR-ing circuitry between my sources, and the IN_HV pin that would prioritize USB as the input.

I reviewed the STEVAL-GPT001V1 solar watch charging evaluation kit schematic and noticed they use an external battery charger (U2) and bypass transistor (Q1) to recharge the battery at a higher current directly on the Vstore net, which is great, but since my batteries are low Ah (1.5-14 mAH), I'm not concerned with speed and would rather prioritize keeping the design to as few components as possible.

Overall what would be a better option for switching between power sources on the fly?

[PMcDo.1]

So my current solution is to use a diode and PMOS MOSFET to switch between RF and USB power. When USB isn't plugged in the PMOS gate is pulled to ground and the RF input supplies power. Likewise if the USB is plugged in without RF power, the diode is forward biased and USB supplies power. If both are plugged in, the higher voltage wins out.

The output of this circuit is passed to the HV_IN pin on the SPV1050 and by adjusting the MPP setting I can change the input impedance of this node to extract maximum power.

If this doesn't work well I will use the STORE net to recharge the battery direction a la the solar powered watch in application note um2260 attached above.

[slaesh]

.. and, how did it worked out? =)

Having the same use-case :)