Please suggest suitable and cheapest possible solution for charging mobile from a 12V battery,
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We have a bunch of different ICs suitable for delivering 5V or even USB-PD to a mobile device. e.g. MPQ4481 can supply 5V with 3A to a USB-C connector – https://www.monolithicpower.com/en/products/automotive/usb-charging-port/mpq4481-aec1.html