This type of MHL (Mobile High definition Link) adapter connects to the tablet's micro usb port and converts the audio and video to HDMI for output through an HDMI port. You also may be required to plug your tabletís charger into the adapter to supply the needed power. Remember the Nexus 7 does not have a MHL port so the Nexus 7 will not charge while using the adapter. I have not tried one so I can not guarantee that it will work.
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