Hi,
I have an application where I need to use 5V 500mA supply. The user is expected to simply plug in a USB cable to meet this need. However, occassionally, for higher power demands, I would like the user to plug in another USB cable to make the available current equal to 1000mA @ 5V. Is there an efficient way to do this without simply tying the two 5V together in parallel?
I prefer USB because the USB chargers coming out with the cell phones are everywhere. I would like to know how to take the principle and scale the power to 1A, 2A, etc by bringing in voltages at different levels.
Here is a summary of the general requirements:
#Vins >1
Vin1 = 4.5V to 5.5V @ 500mA current limited
Vin2 = 4.5 V to 5.5V @ 500mA current limited
Vin3 = 4.5V to 5.5V @ 500mA current limited <--- Would like to support 12V @ 1A instead.
Vout = 5V at 90% efficiency of power transfer. The key is that power transfer is equal amongst all all inputs such that no one input gets drained excessively.
Need a TI reference design to accomplish the above. My budget is flexible but cheaper the better.
Thanks
Rahul
