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I have a USB car charger plugged in the accessory port of my car and I also have a simple bluetooth USB to aux adapter plugged into it. As I start the car, the power drops to the accessory port and the adapter's bluetooth connection disconnects from my phone. It's annoying having to wait for it to reconnect and start my music every time, plus its illegal to operate a phone here in the UK.
I want to know if I could create a simple circuit to hold enough power to keep the adapter running while the power drops. I think the power drop lasts roughly 5-10 seconds and the bluetooth adapter is only 5v 0.1a. Could a capacitor help in this situation?