Semiconductor device
Provided is a semiconductor device including: a first charge pump circuit that generates a first control signal based on electric charge of a first pumping capacitor accumulated through a first drive transistor; a second charge pump circuit that generates a second control signal based on electric charge of a second pumping capacitor accumulated through a second drive transistor; a third charge pump circuit that transfers electric charge between an output terminal and a reference voltage terminal through a third drive transistor; and a fourth charge pump circuit that transfers electric charge between the output terminal and the reference voltage terminal through a fourth drive transistor. Conductive states of the first and third drive transistors are controlled based on the second control signal, and conductive states of the second and fourth drive transistors are controlled based on the first control signal.
1 . A semiconductor device comprising:
an oscillator which generates complementary first and second clock signals;
a first charge pump circuit which supplies, to a first pumping capacitor, electric charge according to a voltage difference between a voltage level of the first clock signal and a voltage of a reference voltage terminal, through a first drive transistor provided in a first current path, and which generates a first control signal based on the electric charge accumulated in the first pumping capacitor;
a second charge pump circuit which supplies, to a second pumping capacitor, electric charge according to a voltage difference between a voltage level of the second clock signal and a voltage of the reference voltage terminal, through a second drive transistor provided in a second current path, and which generates a second control signal based on the electric charge accumulated in the second pumping capacitor;
a third charge pump circuit which includes a third drive transistor that controls a conductive state of a third current path, and which transfers electric charge between the output terminal and the reference voltage terminal through the third current path; and
a fourth charge pump circuit which includes a fourth drive transistor that controls a conductive state of a fourth current path, and which transfers electric charge between the output terminal and the reference voltage terminal through the fourth current path,
wherein conductive states of the first and third drive transistors are controlled based on the second control signal, and
wherein conductive states of the second and fourth drive transistors are controlled based on the first control signal.
2 . The semiconductor device according to claim 1 , wherein
the first pumping capacitor has one terminal supplied with the first clock signal, and the other terminal connected to a first pumping node at which the first control signal is generated,
the first drive transistor is connected between the first pumping node and the reference voltage terminal,
the second pumping capacitor has one terminal supplied with the second clock signal, and the other terminal connected to a second pumping node at which the second control signal is generated, and
the second drive transistor is connected between the second pumping node and the reference voltage terminal.
3 . The semiconductor device according to claim 1 , wherein
the third charge pump circuit includes:
a third pumping capacitor which has one terminal supplied with the first clock signal, and the other terminal connected to a third pumping node, and which accumulates the electric charge; and
a first rectifier element which is connected between the third pumping node and the output terminal, and which allows a current to flow from the output terminal to the third pumping capacitor,
the third drive transistor is connected between the third pumping node and the reference voltage terminal,
the fourth charge pump circuit includes:
a fourth pumping capacitor which has one terminal supplied with the second clock signal, and the other terminal connected to a fourth pumping node, and which accumulates the electric charge; and
a second rectifier element which is connected between the fourth pumping node and the output terminal, and which allows a current to flow from the output terminal to the fourth pumping capacitor, and
the fourth drive transistor is connected between the fourth pumping node and the reference voltage terminal.
4 . The semiconductor device according to claim 3 , wherein
the first and second rectifier elements are diode-connected transistors, and
terminals corresponding to anode terminals of the transistors are connected to the output terminal.
5 . The semiconductor device according to claim 3 , wherein
the first rectifier element is a transistor having a polarity opposite to a polarity of the third drive transistor, and having a control terminal supplied with the second control signal, and
the second rectifier element is a transistor having a polarity opposite to a polarity of the fourth drive transistor, and having a control terminal supplied with the first control signal.
6 . The semiconductor device according to claim 1 , wherein the first to fourth drive transistors are transistors having the same polarity.
7 . The semiconductor device according to claim 1 , wherein the reference voltage terminal is one of a ground terminal and a power supply terminal.
8 . The semiconductor device according to claim 1 , wherein the first and second clock signals have an amplitude range from a ground voltage to a power supply voltage.