Data communication device has data signal generation circuit and transmission circuit on basis of reference voltage and received signal

A data communication device, comprising:

• a signal terminal for inputting a received signal;
• a reference voltage terminal for inputting a first reference voltage;
• a clock generation circuit for generating a clock signal according to the received signal;
• a data signal generation circuit for generating a data signal according to the received signal;
• a transmission circuit for receiving the clock signal and the data signal and outputting a transmission signal to the signal terminal;
• a regulator circuit for generating power supply voltages of the clock generation circuit, the data signal generation circuit, and the transmission circuit on a basis of an internally generated second reference voltage, the received signal, and the first reference voltage;
• a reference voltage circuit for generating the second reference voltage;
• and
• a level shift circuit for level-shifting a pulse of the received signal on a basis of a threshold correlated with the second reference voltage,
• wherein the regulator circuit generates a power supply voltage correlated with the second reference voltage, and there is a correlation between the threshold and the power supply voltage.

A data communication system in which a first data communication device and a second data communication device are connected through at least a signal terminal, wherein

• the first data communication device comprises:
• a voltage amplitude modulation circuit for outputting a signal having portions of different duty ratios and a constant pulse frequency to the second data communication device through the signal terminal on a basis of data;
• and
• a current detection circuit for generating a data signal on a basis of a current running through the signal terminal, and
• the second data communication device comprises:
• a signal terminal for inputting from the first data communication device the signal having portions of different duty ratios and a constant pulse frequency as a received signal;
• a reference voltage terminal for inputting a first reference voltage;
• a clock generation circuit for generating a clock signal according to the received signal;
• a data signal generation circuit for generating a data signal by identifying a duty ratio of the received signal;
• a transmission circuit for outputting a transmission signal to the signal terminal;
• a regulator circuit for generating power supply voltages of the clock generation circuit, the data signal generation circuit, and the transmission circuit on a basis of an internally generated second reference voltage, the received signal, and the first reference voltage,
• a reference voltage circuit for generating the second reference voltage;
• and
• a level shift circuit for level-shifting a pulse of the received signal on a basis of a threshold correlated with the second reference voltage,
• wherein the regulator circuit generates a power supply voltage correlated with the second reference voltage, and there is a correlation between the threshold and the power supply voltage.

A data communication method, comprising steps of:

• inputting to a signal terminal a received signal having portions of different duty ratios and a constant pulse frequency;
• inputting a first reference voltage to a reference voltage terminal;
• generating a clock signal according to the received signal;
• generating a data signal by identifying a duty ratio of the received signal;
• outputting a transmission signal to the signal terminal;
• generating power supply voltages on a basis of an internally generated second reference voltage, the received signal, and the first reference voltage;
• generating the second reference voltage;
• and
• level-shifting a pulse of the received signal on a basis of a threshold correlated with the second reference voltage,
• wherein the step of generating power supply voltages generates a power supply voltage correlated with the second reference voltage, and there is a correlation between the threshold and the power supply voltage.