Low-power high-side voltage regulator

Abstract

Low-power high-side voltage regulator, relating to integrated circuit technology. The present invention includes a DC-DC level conversion module and a control module. A first capacitor (Cboost) is provided between a first reference point (CB) and a second reference point (SW) of the DC-DC level conversion module. A first switch (K1) is provided between a voltage regulating capacitor and a high-level terminal. The control terminal of the first switch (K1) is connected to the control module. It is characterized in that the control module is a voltage detection circuit, and the voltage detection circuit is used to detect the voltage across the first capacitor and switch the state of the first switch (K1) when it reaches a preset threshold. The present invention simplifies the circuit and increases the response speed of the circuit, and the overall power consumption required is less.

Description

Technical Field

[0001] The present invention relates to integrated circuit technology. Background Art

[0002] A voltage regulator is one of the core modules in analog and digital circuits, having a relatively stable reference voltage source. A voltage regulator source is a fixed voltage circuit with a wide range of applications, widely used in the integrated circuit designs such as DC / DC, ADC, DAC, and DRAM, etc., for providing a DC voltage signal independent of the power supply voltage and temperature to the circuit. A traditional DC-DC high-side regulator voltage circuit is as Figure 2 shown. Its principle is to compare the BST voltage with the Vref voltage through a fast hysteresis comparator. The comparison result controls the charging time of the BST voltage to control the voltage of the high-voltage test. Such a high-precision comparator will increase the complexity of the overall circuit design and generate additional power consumption. A low-power application aims to reduce the overall circuit power consumption as much as possible. Therefore, the traditional BST voltage regulator is not suitable for low-power applications. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a high-side voltage regulator circuit with a simple structure and lower power consumption.

[0004] The technical solution adopted by the present invention to solve the above technical problem is a low-power high-side voltage regulator, including a DC-DC level conversion module and a control module. A first capacitor is provided between the first reference point and the second reference point of the DC-DC level conversion module. A first switch is provided between the first capacitor and the high-level terminal, and the control end of the first switch is connected to the control module. The control module is a voltage detection circuit for detecting the voltage across the first capacitor and switching the state of the first switch when it reaches a preset threshold.

[0005] Further, the control module includes:

[0006] A first PMOS transistor, whose source is connected to the first reference point through a first resistor, and whose gate and drain are connected to the second reference point through a current source;

[0007] A second PMOS transistor, whose source is connected to the first reference point through a second resistor, whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain and gate of a first NMOS transistor;

[0008] A third PMOS transistor, whose source is connected to the first reference point through a third resistor, whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain of a second NMOS transistor;

[0009] The fourth PMOS transistor, whose source is connected to the first reference point through a fourth resistor, gate is connected to the gate of the first PMOS transistor, and drain is connected to the output terminal through an inverter;

[0010] The first NMOS transistor, whose source is connected to the second reference point through a fifth resistor;

[0011] The second NMOS transistor, whose source is connected to the second reference point through a sixth resistor, and gate is connected to the gate of the first NMOS transistor;

[0012] The third NMOS transistor, whose source is connected to the drain of the fourth PMOS transistor, and drain and gate are connected to the drain of the second NMOS transistor;

[0013] The fourth NMOS transistor, whose source is connected to the second reference point, and gate is connected to the drain of the second NMOS transistor;

[0014] The Zener diode, whose positive electrode is connected to the drain of the second NMOS transistor, and negative electrode is connected to the first reference point.

[0015] The present invention designs the entire circuit in an isolation layer through an isolation process, enabling it to be applied to the working environment under the floating voltage of the high-voltage side; secondly, it reduces a relatively high-precision comparator structure, increases the circuit stability by adding a hysteresis circuit, simplifies the circuit and increases the response speed of the circuit, and requires less overall power consumption; the present invention limits the high-voltage side power supply voltage through the breakdown of a specific device, the Zener diode. Brief Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of a high-voltage DC-DC.

[0017] Figure 2 is a circuit diagram of the control module of the prior art.

[0018] Figure 3 is the low-power high-voltage side voltage regulator proposed by the present invention; Detailed Embodiments

[0019] The voltage regulator includes a DC-DC level conversion module and a control module. Figure 1 Shows the structure of the high-voltage DC-DC level conversion module, including a first switch K1, a second switch K2, a third switch K3, a first capacitor Cboost, a second capacitor C, a first diode D, a first inductor L, and a resistor R. Figure 2 is the control module of the prior art, which requires a comparator.

[0020] See Figure 3 , the control module of the present invention is a voltage detection circuit, and the voltage detection circuit is used to detect the voltage across the first capacitor and switch the state of the first switch K1 when it reaches a preset threshold.

[0021] Specifically, the control module of the present invention includes:

[0022] The first PMOS transistor MP1, whose source is connected to the first reference point through the first resistor R1, and whose gate and drain are connected to the second reference point through a current source;

[0023] The second PMOS transistor MP2, whose source is connected to the first reference point through the second resistor R2, whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain and gate of the first NMOS transistor;

[0024] The third PMOS transistor MP3, whose source is connected to the first reference point through the third resistor R3, whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain of the second NMOS transistor MN2;

[0025] The fourth PMOS transistor MP4, whose source is connected to the first reference point through the fourth resistor R4, whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the output terminal through an inverter;

[0026] The first NMOS transistor MN1, whose source is connected to the second reference point through the fifth resistor R5;

[0027] The second NMOS transistor MN2, whose source is connected to the second reference point through the sixth resistor R6, and whose gate is connected to the gate of the first NMOS transistor;

[0028] The third NMOS transistor MN3, whose source is connected to the drain of the fourth PMOS transistor, and whose drain and gate are connected to the drain of the second NMOS transistor;

[0029] The fourth NMOS transistor MN4, whose source is connected to the second reference point, and whose gate is connected to the drain of the second NMOS transistor;

[0030] The Zener diode DW, whose positive electrode is connected to the drain of the second NMOS transistor, and whose negative electrode is connected to the first reference point.

[0031] When the circuit works, the current source I provides a bias current for the circuit, and the current mirror starts to work. At this time, the CB voltage has not reached the magnitude to break down the Zener diode, the first switch K1 is closed, and the first capacitor Cboost is in the charging state, and the CB voltage increases continuously. When the CB voltage rises to the magnitude to break down the Zener diode, the Zener diode is broken down, the output signal of the circuit is reversed, the first switch K1 is disconnected, and the charging of the first capacitor Cboost is stopped, and the CB voltage no longer increases. The current source I can control the overall circuit current magnitude and reduce the overall circuit power consumption. The third NMOS transistor MN3 can accelerate the circuit response speed.

[0032] ]The main optimization directions of the present invention for the circuit are low power consumption, high voltage, and response speed. A current source is borrowed to control the overall circuit power consumption problem; through an isolation process, the overall circuit design is in an isolation layer and can be applied to the working environment under the floating voltage on the high-voltage side; compared with the traditional voltage regulator, a high-precision comparator structure is reduced. The present invention increases the circuit stability by adding a hysteresis circuit, simplifies the circuit, and increases the response speed of the circuit; the breakdown voltage characteristic of the specific device Zener diode structure is borrowed to limit the power supply voltage on the high-voltage side.

Claims

1. Low-power high-side voltage regulator, comprising a DC-DC level conversion module and a control module. A first capacitor (Cboost) is provided between a first reference point (CB) and a second reference point (SW) of the DC-DC level conversion module. A first switch (K1) is provided between the first capacitor and the high-level terminal. The control terminal of the first switch (K1) is connected to the control module, characterized in that, The control module is a voltage detection circuit, and the voltage detection circuit is used to detect the voltage across the first capacitor and switch the state of the first switch (K1) when it reaches a preset threshold value; The control module includes: A first PMOS transistor (MP1), whose source is connected to a first reference point through a first resistor (R1), and whose gate and drain are connected to a second reference point through a current source; A second PMOS transistor (MP2), whose source is connected to the first reference point through a second resistor (R2), whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain and gate of the first NMOS transistor; A third PMOS transistor (MP3), whose source is connected to the first reference point through a third resistor (R3), whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the drain of the second NMOS transistor (MN2); A fourth PMOS transistor (MP4), whose source is connected to the first reference point through a fourth resistor (R4), whose gate is connected to the gate of the first PMOS transistor, and whose drain is connected to the output terminal through an inverter; A first NMOS transistor (MN1), whose source is connected to the second reference point through a fifth resistor (R5); A second NMOS transistor (MN2), whose source is connected to the second reference point through a sixth resistor (R6), and whose gate is connected to the gate of the first NMOS transistor; A third NMOS transistor (MN3), whose source is connected to the drain of the fourth PMOS transistor, and whose drain and gate are connected to the drain of the second NMOS transistor; A fourth NMOS transistor (MN4), whose source is connected to the second reference point, whose gate is connected to the drain of the second NMOS transistor, and whose drain is connected to the drain of the fourth PMOS transistor; A Zener diode, whose positive electrode is connected to the drain of the second NMOS transistor, and whose negative electrode is connected to the first reference point.

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