Abstract: A comparator includes a sampling capacitor, a first switching unit which is connected to an input end of the sampling capacitor and which applies an input signal to the input end of the sampling capacitor, a second switching unit which is connected to the input end of the sampling capacitor and which applies a reference signal to the input end of the sampling capacitor, an output transistor connected to an output end of the sampling capacitor in a source follower connection manner or an emitter follower connection manner, and a third switching unit which is connected to an output end of the sampling capacitor and which maintains maintaining a voltage at the output end of the sampling capacitor to be constant. The input signal is compared with the reference signal.

Abstract: The present invention is relative to a starter circuit for starting and re-starting a main circuit (20) in startup and during the unusual operation of the main circuit. The starter circuit includes a startup signal supplying unit (11) for supplying a stop signal for stopping the operation of the main circuit when the standby signal is at a standby level, supplying a startup signal to a circuit startup node (22) of the main circuit when the standby signal is changed from the standby level to the startup level and for halting the supply of the stop signal.

Abstract: A differential amplifier has an in-phase input terminal to which an input signal is applied through a first switching unit, an anti-phase input terminal to which a reference signal is applied through a second switching unit, and a third switching unit between the in-phase and anti-phase input terminals. The potential difference between the in-phase and anti-phase input terminals is differentially amplified by setting the first and second switching units to be on and the third switching unit to be off. Also, the in-phase and anti-phase input terminals are short-circuited to have a high impedance by setting the first and second switching units to be off and the third switching unit to be on.

Abstract: The present invention is relative to a starter circuit for starting and re-starting a main circuit (20) in startup and during the unusual operation of the main circuit. The starter circuit includes a startup signal supplying unit (11) for supplying a stop signal for stopping the operation of the main circuit when the standby signal is at a standby level, supplying a startup signal to a circuit startup node (22) of the main circuit when the standby signal is changed from the standby level to the startup level and for halting the supply of the stop signal.

Abstract: A start-up circuit supplying a start-up current to a band gap reference voltage circuit at the time of start-up so as to start the band gap reference voltage circuit reliably, which stops the supply of the start-up current after the band gap reference voltage circuit starts operation in response to an output voltage of an operational amplifier supplied as the reference voltage of the band gap reference voltage circuit and, further, a voltage supply circuit, including such a start-up circuit and a band gap reference voltage circuit, which operates under the control of a feedback loop formed by the operational amplifier and outputs a constant voltage without dependency on the power supply voltage and the temperature.

Abstract: A level shift circuit reduced in a circuit area and conversion delay when converting a signal level, capable of operating at a high speed, expanded in the range of the operatable voltage, and capable of operating at a low voltage, including a first transistor connected between a voltage Va source and an output terminal, a second transistor connected between a voltage Vc source and an output terminal, a third transistor connected between a voltage Vc source and a gate of the second transistor, a fourth transistor connected between a voltage Va source and the gate of the second transistor, a fifth transistor connected between the ground and the output terminal, and a sixth transistor connected between the ground and the gate of the second transistor, wherein a connection point of an output terminal and the first, second, and fifth transistors is connected to a gate of the third transistor, gates of the fourth and fifth transistors are connected to an input terminal, and an inverted signal of an input signal to