A smart switch design in an external data storage or a flash memory reader/writer application that controls a power on/off to both a data storage device and an electronic bridge board inside a interface cable, the external data storage including: an enclosure for protecting interior elements; a switch with first and second ends, the first end connected to a wire of the electronic bridge board for receiving a power signal from a computer via an interface cable, the second end is connected to a power signal pin of the data storage device and an ASIC of the electronic bridge board; when the switch turns on (or the flash memory card insert into said slot) the data storage device (or the flash memory card) and the ASIC of the electronic bridge board gets the power signal from the computer and automatically issues the necessary handshake signals to the computer to establish the electrical communication to the data storage device (or the flash memory card).
