Operational comparator, differential output circuit, and semiconductor integrated circuit

An operational comparator comprising:

• a first and a second current mirror circuits that receives and operates by a first power voltage from a first power source;
• a first load circuit that is coupled to a sense side of the first current mirror circuit;
• a second load circuit that is coupled to a sense side of the second current mirror circuit;
• a first current source circuit that receives a second power voltage from a second power source, and supplies a constant current to the first and the second load circuits;
• and
• a third current mirror circuit that receives the power voltage from the second power source, and includes a first and a second transistors, the first transistor is coupled to a mirror side of the first current mirror circuit, the second transistor is coupled to a mirror side of the second current mirror circuit, wherein
• the first load circuit includes a third transistor that has a gate terminal with which a reference voltage is coupled,
• the second load circuit includes a fourth transistor and a fifth transistor coupled to the fourth transistor in parallel,
• a gate terminal of the fourth transistor receives a first signal, and
• a gate terminal of the fifth transistor receives a second signal whose phase is opposite to a phase of the first signal.

A differential output circuit, comprising:

• a digital circuits that receives an each power voltage from a first and third power sources, and generate a first non-inverted output signal and a second inverted output signal related on the first input signal;
• a first output circuit that receives an each power voltage from the first and a fourth power sources, and controls an output voltage for one side signal in a differential signal related on the first output signal;
• a second output circuit that receives and operates by an each power voltage from the first and the fourth power sources, and controls an output voltage for the other side signal in the pair of the differential signal related on the second output signal;
• and
• a first common voltage control circuit that receives and operates by an each power voltage from the first and a second power sources, and outputs the comparison result of both voltages of output terminals of the first output circuit and the second output circuit with a reference voltage, wherein
• the first output circuit has a first control circuit that controls an output voltage for one side signal in the differential signal,
• the second output circuit has a second control circuit that controls an output voltage for other side signal in the differential signal, and
• the first and the second control circuits control voltages for one side signal and other side signal in the differential signal to adjust a common voltage of the differential signal related on the comparison result from the first common voltage control circuit.

A differential output circuit, comprising:

• a digital circuit that receives an each power voltage from a first and a third power sources, and generates a first non-inverted output signal and a second inverted output signal, related on the first input signal;
• a phase adjusting circuit that receives an each power voltage from a first and a fourth power sources, and generates a third output signal and a fourth output signal which has a different phase by 180 degrees from that of the third output signal, related on the first non-inverted output signal and the second inverted output signal;
• a first output circuit that receives an each power voltage from the first and the fourth power sources, and generates one side signal in a differential signal related on the third output signal;
• a second output circuit that receives an each power voltage from the first and the fourth power sources, and generates other side signal of differential signal related on the fourth output signal;
• and
• a first common voltage adjusting circuit that receives an each power voltage from the first and a second power sources, and outputs a comparison result of both voltages of output terminals of the first output circuit and the second output circuit with a reference voltage, wherein
• the first output circuit has a first control circuit that controls an output voltage for one side signal in the differential signal,
• the second output circuit has a second control circuit that controls an output voltage for other side signal in the differential signal, and
• the first and the second control circuits control voltages for one side signal and other side signal in the differential signal to adjust a common voltage of the differential signal, related on the comparison result from the first common voltage control circuit.