US 12,436,551 B2
Power-supply stabilization circuit
Keizo Matsumoto, Okayama (JP); and Shinichi Watanabe, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 18/563,642
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed May 19, 2022, PCT No. PCT/JP2022/020798
§ 371(c)(1), (2) Date Nov. 22, 2023,
PCT Pub. No. WO2023/002744, PCT Pub. Date Jan. 26, 2023.
Claims priority of application No. 2021-120013 (JP), filed on Jul. 20, 2021.
Prior Publication US 2024/0288891 A1, Aug. 29, 2024
Int. Cl. G05F 1/56 (2006.01); G05F 1/46 (2006.01)
CPC G05F 1/56 (2013.01) [G05F 1/468 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A power-supply stabilization circuit that stabilizes a constant-voltage signal outputted from a constant-voltage power supply and including a noise component, and outputs the constant-voltage signal that has been stabilized from an output terminal, the power-supply stabilization circuit comprising:
a first transistor that is disposed in a second path that connects a first path and a first constant-voltage portion, the first path connecting the constant-voltage power supply and the output terminal, the first constant-voltage portion having a constant voltage at a voltage level lower than a voltage level of a voltage of the constant-voltage signal outputted from the constant-voltage power supply;
a first shunt resistor that is connected between the first transistor and the first constant-voltage portion;
a second transistor that is disposed in a third path that connects the first path and a second constant-voltage portion having a constant voltage at a voltage level higher than the voltage level of the voltage of the constant-voltage signal outputted from the constant-voltage power supply;
a second shunt resistor that is connected between the second transistor and the second constant-voltage portion;
a third transistor that is disposed in a fourth path and current mirror-connected to the first transistor, the fourth path connecting the first constant-voltage portion and the second constant-voltage portion and different from the second path and the third path;
a fourth transistor that is disposed between the second constant-voltage portion and the third transistor in the fourth path, and current mirror-connected to the second transistor;
a differential amplifier that includes a first positive input terminal to which a first reference voltage is inputted and a first negative input terminal which is connected to the first path; and
a first low-pass filter that is connected between a fifth path and a node, in the fourth path, that is present between the third transistor and the fourth transistor, the fifth path connecting the first path and the first negative input terminal,
wherein an added signal is inputted to the first negative input terminal, the added signal being obtained by adding the constant-voltage signal and an output signal of the first low-pass filter,
the differential amplifier performs inverting amplification on a difference between a voltage of the added signal and the first reference voltage, and outputs a first difference signal obtained by the inverting amplification to the first transistor and the second transistor, and
the power-supply stabilization circuit performs push-pull operations to cause an electric current that is responsive to the first difference signal to flow into the first constant-voltage portion from the first path via the first transistor and the first shunt resistor, when the voltage of the added signal is higher than the first reference voltage, and cause an electric current that is responsive to the first difference signal to flow into the first path from the second constant-voltage portion via the second shunt resistor and the second transistor, when the voltage of the added signal is lower than the first reference voltage.