Patent ID: 8155586

Claim:
A portable device for data communication using a body as a conductor to transmit data to a receiver, the portable device comprising: a controller unit to control processing of data to be transmitted; a current limiting circuit to limit a current of a signal corresponding to the data to be transmitted to a predetermined value; and transmitting electrodes connected to the current limiting circuit and contacted with the body to generate electric potential difference therebetween, so that the signal having the current of predetermined value flows from the transmitting electrode having higher electric potential through the body to the receiver and sinks to the transmitting electrode having lower electric potential, wherein the controller unit changes the transmitter electrodes according to the data to be transmitted so that a digital “1” is represented as a first state when a plus voltage is applied to a first transmitting electrode and a second transmitting electrode serves as a ground, and a digital “0” is represented as a second state when the first transmitting electrode serves as the ground and the plus voltage is applied to the second transmitting electrode.