CN-116414169-B - Low-voltage drop voltage stabilizing circuit

Abstract

The invention discloses a low-dropout voltage stabilizing circuit. The low-dropout voltage regulator comprises a differential amplifying circuit, a self-stabilizing second-stage amplifying circuit, an output circuit and a frequency compensation circuit. The differential amplifying circuit is electrically connected with the self-stabilizing second-stage amplifying circuit. The self-stabilizing second-stage amplifying circuit is electrically connected with the output circuit. The frequency compensation circuit is arranged among the output end of the self-stabilizing second-stage amplifying circuit, the second end of the output switch component of the output circuit and the third end of the output switch component of the output circuit.

Inventors

• WANG YOUFA
• SHI WEI
• YI DAMAN

Assignees

• 光宝科技新加坡私人有限公司

Dates

Publication Date

20260512

Application Date

20220105

Claims (10)

1. 1. A low dropout voltage regulator circuit, comprising: the differential amplifying circuit comprises an output end and a feedback end; The second-stage amplifying circuit comprises an input end and an output end, the output end of the differential amplifying circuit is electrically connected with the input end of the second-stage amplifying circuit, the second-stage amplifying circuit comprises a first amplifying transistor component and a second amplifying transistor component, the first amplifying transistor component comprises a first end, a second end and a third end, the second amplifying transistor component comprises a first end, a second end and a third end, the first end of the first amplifying transistor component is electrically connected with an input voltage, the second end of the first amplifying transistor component is electrically connected with the second end of the second amplifying transistor component to form the input end of the second-stage amplifying circuit, and the third end of the first amplifying transistor component is connected with the first end of the second amplifying transistor component to form the output end of the differential amplifying circuit; An output circuit including an output transistor assembly including a first end, a second end and a third end, the first end of the output transistor assembly being electrically connected to the input voltage, the second end of the output transistor assembly being electrically connected to the output end of the second stage amplifying circuit, the third end of the output transistor assembly being electrically connected to the feedback circuit, the feedback circuit being connected to the feedback end of the differential amplifying circuit, and A frequency compensation circuit disposed between said output terminal of said second stage amplifying circuit, said second terminal of said output transistor assembly, and said third terminal of said output transistor assembly; The first amplifying transistor component is a P-type metal oxide field effect transistor, the second amplifying transistor component is an N-type metal oxide field effect transistor, the first end of the first amplifying transistor component is a source end, the second end of the first amplifying transistor component is a gate end, the third end of the first amplifying transistor component is a drain end, the first end of the second amplifying transistor component is a drain end, the second end of the second amplifying transistor component is a gate end, and the third end of the second amplifying transistor component is a source end.
2. 2. The low dropout voltage regulator circuit according to claim 1, wherein said frequency compensation circuit includes a first compensation impedance and a first compensation capacitor, said first compensation impedance being connected in series with said first compensation capacitor, said first compensation impedance having a value between 200 ohms and 30K ohms, said first compensation capacitor having a value between 4 picofarads and 50 picofarads.
3. 3. The low dropout voltage regulator circuit according to claim 1, wherein said frequency compensation circuit includes a first compensation impedance, a first compensation capacitor, a second compensation impedance, and a second compensation capacitor, said first compensation impedance being connected in series with said first compensation capacitor, said second compensation impedance being connected in parallel with said second compensation capacitor, said first compensation capacitor being connected in series with said second compensation impedance, said second compensation capacitor.
4. 4. The low dropout voltage regulator circuit according to claim 1, wherein said frequency compensation circuit comprises a compensation transistor assembly and a third compensation capacitor, said compensation transistor assembly comprising a first terminal, a second terminal and a third terminal, said first terminal of said compensation transistor assembly being electrically connected to said output terminal of said second stage amplifying circuit and said second terminal of said output transistor assembly, said second terminal of said compensation transistor assembly being electrically connected to said third terminal of said compensation transistor assembly and said third compensation capacitor.
5. 5. The low dropout voltage regulator circuit according to claim 1, wherein said third terminal of said second amplifying transistor assembly of said second stage amplifying circuit is electrically connected to a ground potential.
6. 6. The low dropout voltage regulator circuit according to claim 1, wherein said second stage amplifying circuit further comprises a third amplifying transistor assembly, said third amplifying transistor assembly comprising a first end, a second end and a third end, said first end of said third amplifying transistor assembly being electrically connected to said third end of said second amplifying transistor assembly and said second end of said third amplifying transistor assembly, said third end of said third amplifying transistor assembly being electrically connected to a ground potential.
7. 7. The low dropout regulator circuit according to claim 6, wherein said first amplifying transistor assembly includes a first channel width, said second amplifying transistor assembly includes a second channel width, said first channel width is 1/2 to 1/15 of said second channel width, said third amplifying transistor assembly includes a third channel width, said third channel width is more than twice said first channel width.
8. 8. The low dropout regulator circuit according to claim 1, wherein said differential amplifier circuit comprises a current source, a first differential transistor element, a second differential transistor element, a third differential transistor element and a fourth differential transistor element, said first differential transistor element comprises a first end, a second end and a third end, said second differential transistor element comprises a first end, a second end and a third end, said third differential transistor element comprises a first end, a second end and a third end, said fourth differential transistor element comprises a first end, a second end and a third end, said current source is electrically connected to said first end of said first differential transistor element and to said first end of said third differential transistor element, said second end of said first differential transistor element is connected to a reference voltage, said third end of said first differential transistor element is electrically connected to said second end of said second differential transistor element, said second end of said differential transistor element is electrically connected to said second end of said differential transistor element, said third end of said differential transistor element is electrically connected to said second end of said second differential transistor element, said third end of said differential transistor element is electrically connected to said third end of said differential amplifier circuit, said third end is electrically connected to said third end of said differential transistor element, the third terminal of the fourth differential transistor element is electrically connected to the ground potential.
9. 9. The low dropout voltage regulator circuit according to claim 8, wherein said feedback circuit comprises a first feedback impedance and a second feedback impedance, said first feedback impedance being connected in series with said second feedback impedance, said first feedback impedance and said second feedback impedance being a resistor or a mosfet connected in the form of a diode, said first differential transistor element and said third differential transistor element being a pmos fet, said second differential transistor element and said fourth differential transistor element being an nmos fet.
10. 10. The low dropout regulator circuit according to claim 1, wherein the amplifier circuit formed by said differential amplifier circuit and said second stage amplifier circuit is self-stabilizing without a compensation circuit being provided between said differential amplifier circuit and said second stage amplifier circuit.

Description

Low-voltage drop voltage stabilizing circuit Technical Field The present invention relates to a low dropout voltage regulator circuit, and more particularly to a low dropout voltage regulator circuit with a simple structure. Background In most conventional low dropout voltage regulator circuits, a compensation capacitor with a large impedance value or a complex circuit is required to be externally arranged. How to provide a low-dropout voltage regulator circuit with a simple circuit structure to overcome the above-mentioned drawbacks has become one of the important issues to be solved by the industry. Disclosure of Invention The invention aims to solve the technical problem of providing a low-voltage drop voltage stabilizing circuit aiming at the defects of the prior art, and is characterized by comprising a differential amplifying circuit, a voltage stabilizing circuit and a voltage stabilizing circuit, wherein the differential amplifying circuit comprises an output end and a feedback end; the second-stage amplifying circuit comprises a first amplifying transistor component and a second amplifying transistor component, wherein the first amplifying transistor component comprises a first end, a second end and a third end, the second amplifying transistor component comprises a first end, a second end and a third end, the first end of the first amplifying transistor component is electrically connected with an input voltage, the second end of the first amplifying transistor component is electrically connected with the second end of the second amplifying transistor component to form the input end of the second amplifying transistor component, and is connected with the output end of the differential amplifying circuit, the third end of the first amplifying transistor component is connected with the first end of the second amplifying transistor component to form the first end of the second amplifying transistor component, the first end of the first amplifying transistor component is electrically connected with the first end of the first amplifying transistor component, the first end of the first amplifying transistor component is electrically connected with the first end of the feedback transistor component, the first end of the feedback transistor component is electrically connected with the first end of the feedback transistor component, and the feedback transistor component is electrically connected with the first end of the feedback transistor component, the feedback circuit is connected with the feedback end of the differential amplifying circuit, and the frequency compensation circuit is arranged among the output end of the second-stage amplifying circuit, the second end of the output transistor component and the third end of the output transistor component. Preferably, the frequency compensation circuit comprises a first compensation impedance and a first compensation capacitor, the first compensation impedance is connected with the first compensation capacitor in series, the first compensation impedance is between 200 ohms and 30K ohms, and the first compensation capacitor is between 4 picofarads and 50 picofarads. Preferably, the frequency compensation circuit includes a first compensation impedance, a first compensation capacitor, a second compensation impedance and a second compensation capacitor, the first compensation impedance is connected in series with the first compensation capacitor, the second compensation impedance is connected in parallel with the second compensation capacitor, and the first compensation capacitor is connected in series with the second compensation impedance and the second compensation capacitor. Preferably, the frequency compensation circuit includes a compensation transistor assembly and a third compensation capacitor, the compensation transistor assembly includes a first end, a second end and a third end, the first end of the compensation transistor assembly is electrically connected to the output end of the second stage amplifying circuit and the second end of the output transistor assembly, and the second end of the compensation transistor assembly is electrically connected to the third end of the compensation transistor assembly and the third compensation capacitor. Preferably, the third terminal of the second amplifying transistor component of the second stage amplifying circuit is electrically connected to a ground potential. Preferably, the second stage amplifying circuit further includes a third amplifying transistor assembly, the third amplifying transistor assembly includes a first end, a second end and a third end, the first end of the third amplifying transistor assembly is electrically connected to the third end of the second amplifying transistor assembly and the second end of the third amplifying transistor assembly, and the third end of the third amplifying transistor assembly is electrically connected to a ground potential. Preferably, the first amplifying t