LDO, BUCK and Load Switch adaptive hybrid power management method

Abstract

According to the LDO, BUCK and Load Switch adaptive hybrid power supply management method, an appropriate power supply mode is judged by detecting output voltage and load current in real time, and then a corresponding control circuit is automatically switched through internal logic, so that expansion of an electrical load application scene and optimization of efficiency are realized; an LDO (Low Dropout Regulator) module, a Charge Pump module, a Load Switch LOGIC (Low Dropout Regulator) module, an LDO LOGIC module, a BUCKLOGIC module, a Level Shift module, a logic control module, a signal gating module, a power tube, a current source, a current mirror circuit and a voltage comparison circuit which are connected through wires are adopted as equipment adapting to the hybrid power supply management method. According to the invention, the technical characteristics of LDO, BUCK and Load Switch are mainly utilized to carry out complementarity hybrid design, the self-adaptability is better, a proper power supply mode is judged by detecting output voltage and load current, dynamic switching can be carried out according to load conditions by automatically switching to a corresponding control circuit through logic, the output range is wide, the efficiency is optimal, and the self-adaptive power supply circuit is suitable for large-scale popularization and application. And the application range of the single power supply management chip is greatly expanded.

Description

Technical Field

[0001] The invention relates to the technical field of power supply, and in particular to an LDO, BUCK and Load Switch adaptive hybrid power supply management method. Background Art

[0002] In the application of integrated circuits, power management chips are widely used, and the development of power management technology is of great significance to improving the overall performance of products. Common power management chips include LDO, BUCK and LoadSwitch. Among them, LDO has good noise and PSRR performance. It is suitable for situations where the load current is small and the input-output voltage difference is not large. The smaller the voltage difference, the higher the efficiency. However, LDO is not suitable for application scenarios with large load currents. In this working scenario, BUCK has a good performance. Under high current load conditions, BUCK efficiency is very high; however, under low load current conditions, BUCK efficiency is not ideal. In addition, both LDO and BUCK are step-down circuits, and the output voltage is less than the input voltage, so their application has limitations. LoadSwitch has the advantages of equal output and input voltages, and extremely low power consumption inside the chip, but it has the disadvantage of low efficiency. Therefore, in actual production applications, it is often necessary to select power management chips separately according to the usage scenario. A single power management chip cannot achieve the optimal choice of output and efficiency. Summary of the invention

[0003] In order to overcome the drawbacks of existing LDO, BUCK and Load Switch circuit management chips due to technical limitations as described in the background, the present invention provides a LDO, BUCK and Load Switch adaptive hybrid power management method that utilizes the respective technical characteristics of LDO, BUCK and Load Switch to perform a complementary hybrid design, has better adaptability, can be dynamically switched according to the load (output voltage and current to the load) conditions, has a wide output range, optimal efficiency, is suitable for more application scenarios, and greatly expands the scope of use of a single power management chip.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A LDO, BUCK and Load Switch adaptive hybrid power management method, characterized in that the appropriate power mode is judged by real-time detection of output voltage and load current, and then the corresponding control circuit is automatically switched through internal logic to achieve expansion of power load application scenarios and optimization of efficiency, and an LDO module, a Charge Pump module, a LoadSwitch LOGIC module, an LDO LOGIC module, a BUCK LOGIC module, a Level Shift module, a logic control module, a signal gating module, a power tube, a current source, a current mirror circuit, and a voltage comparison circuit are used as devices adapted to the hybrid power management method; the current mirror circuit has two paths and the voltage comparison circuit has three paths; the LDO module, the Charge Pump module, the Load Switch LOGIC module, the LDO LOGIC module, the BUCK LOGIC module, the Level Shift module, the logic control module, the signal gating module, the power tube, the current source, the current mirror circuit, and the voltage comparison circuit are connected via wires; the power output end of the power tube is electrically connected to the power input end of the power load; the LDO module is used to provide power for the operation of the entire device, and the Charge Pump ... The function of the Pump module is to boost the power supply voltage and provide the voltage required for turning on the power tube; the function of the Load Switch LOGIC module, the LDO LOGIC module, and the BUCK LOGIC module is to provide the logic function in the corresponding working mode; the function of the Level Shift module is to convert the low-voltage domain signal into a high-voltage domain signal, and the function of the logic control module is to select the corresponding working mode according to the corresponding criterion; the function of the signal selection module is to select the corresponding working channel, and the function of the power tube is to provide a charging and discharging channel; the function of the current source is to provide a reference current, the function of the current mirror circuit is to copy the current in proportion, and the function of the comparison circuit is to compare the voltage.

[0006] Furthermore, there are two power tubes, and the two power tubes are connected via wires.

[0007] Furthermore, the first current mirror circuit is composed of two MOS tubes, which are connected via wires, and the second current mirror circuit is composed of three MOS tubes and three resistors, which are connected via wires.

[0008] Furthermore, the signal gating module is composed of five transmission tubes, and the five transmission tubes are connected via wires.

[0009] Furthermore, the third voltage comparison circuit is composed of three comparator modules, and the three comparator modules are connected via wires.

[0010] Furthermore, the logic function module includes ten logic gate module circuits, and the ten logic gate module circuits are connected via wires.

[0011] Compared with the prior art, the present invention has the following beneficial effects: the present invention mainly utilizes the respective technical characteristics of LDO, BUCK and Load Switch to perform a complementary hybrid design, has better adaptability, determines the appropriate power supply mode by real-time detection of output voltage and load current, and then automatically switches to the corresponding control circuit through internal logic. It can be dynamically switched according to the load (output voltage and current to load) conditions, has a wide output range, and optimal efficiency, which greatly expands the use scope of a single power management chip, realizes the expansion of application scenarios and the optimization of efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 It is an invented DO, BUCK and Load Switch hybrid power management application circuit diagram.

[0014] Figure 2 , 3 The invention discloses a hybrid power management circuit diagram of LDO, BUCK and Load Switch.

[0015] Figure 4 It is a schematic diagram of the working principle and meaning of the logic judgment module of the present invention. DETAILED DESCRIPTION

[0016] Figure 1 , 2As shown in , an LDO, BUCK and Load Switch adaptive hybrid power management method determines the appropriate power mode by real-time detection of output voltage and load current, and then automatically switches to the corresponding control circuit through internal logic to achieve the expansion of power load application scenarios and optimization of efficiency. LDO module, Charge Pump module, Load Switch LOGIC module, LDO LOGIC module, BUCK LOGIC module, Level Shift module, logic control module, signal gating module, power tube, current source, current mirror circuit, voltage comparison circuit are used as devices adapted to the hybrid power management method; the current mirror circuit has two paths and the voltage comparison circuit has three paths; the LDO module, Charge Pump module, Load Switch LOGIC module, LDO LOGIC module, BUCK LOGIC module, Level Shift module, logic control module, signal gating module, power tube, current source, current mirror circuit, and voltage comparison circuit are connected via wires; the power output end of the power tube is electrically connected to the power input end of the power load; the LDO module is used to provide power for the overall device to work, and the Charge The function of the Pump module is to boost the power supply voltage and provide the voltage required for turning on the power tube; the function of the Load Switch LOGIC module, the LDO LOGIC module, and the BUCK LOGIC module is to provide the logic function in the corresponding working mode; the function of the Level Shift module is to convert the low-voltage domain signal into a high-voltage domain signal, and the function of the logic control module is to select the corresponding working mode according to the corresponding criterion; the function of the signal selection module is to select the corresponding working channel, and the function of the power tube is to provide a charging and discharging channel; the function of the current source is to provide a reference current, the function of the current mirror circuit is to copy the current in proportion, and the function of the comparison circuit is to compare the voltage.

[0017] Figure 1 , 2 As shown in Figure 3, NM1 and NM2 are power tubes, and NM1 and NM2 are connected by wires. Current Source is a reference current source, and the current size of the current source is I 0 MOS tubes NM1 and NM3 form a first mirror circuit. MOS tubes NM1 and NM3 are connected by wires. The currents flowing through MOS tubes NM1 and NM3 are I 1 ,I 2 , and the size parameters of NM1 and NM3 satisfy the relationship Then there is I 1 =kI 2 , if k is large enough, the load current is approximately I 1MOS tubes NM4, NM5, NM6 and resistors R1, R2, R3 form a second current mirror circuit. MOS tubes NM4, NM5, NM6 and resistors R1, R2, R3 are connected via wires. The currents flowing through MOS tubes NM4, NM5, NM6 are I 3 ,I 4 ,I 5 , and the size parameters satisfy the relationship Then there is I 3 =I 4 =I 5 =I 0 ; The current flowing through resistors R1, R2, and R3 is I 2 ,I 4 ,I 5 , the resistance values ​​of resistors R1, R2, and R3 are R 1 , R 2 , R 3 , then the voltage across R1, R2, and R3 is I 4 *R 2 =I 0 *R 2 ,I 5 *R 3 =I 0 *R 3 , the potentials of A, B, and C are VDD1-I 0 *R 2 、VDD1-I 0 *R 3 U1 is the first voltage comparison circuit, which compares the potentials of points A and B. U3 is an inverting circuit. When the potential of point B is greater than that of point A, the output OUT3 is high and OUT3_N is low. When OUT3 is high level and OUT3_N is low level, select appropriate k, I 0 , R 1 , R 2 , satisfying the relation That is, when the current flowing through NM1 is greater than 100mA, the output OUT3 is high and OUT3_N is low. U2 is the second voltage comparison circuit, which compares the potentials of points A and C. When the potential of point C is greater than that of point A, the output OC is high. When OC is high, take appropriate k, I 0 , R 1 , R 3 , satisfying the relation That is, when the current flowing through NM1 is greater than 3A, the output OC is high, indicating that the output current is abnormally overcurrent. The current overcurrent value can be adjusted according to the actual application. The input of the LDO module is the voltage source SVIN, and the output is VDD, which supplies power to the entire system. ChargePump is a boost circuit that increases the power supply voltage PVIN to VDD1.

[0018] Figure 1 , 2As shown in Figure 3, LoadSwitchLOGIC completes the logic function in LoadSwitch mode. LS_EN is the module enable signal. When it is at a high level, the circuit system enters LoadSwitch mode, LoadSwitchLOGIC starts working, and generates a control signal LS_ctr. LDO LOGIC completes the logic function in LDO mode. LDO_EN is the module enable signal. When it is at a high level, the circuit system enters LDO mode, LDOLOGIC starts working, and generates a control signal LDO_ctr. FB is the feedback voltage input, which is used to adjust the output voltage. BUCKLOGIC completes the logic function in BUCK mode. BUCK_EN is the module enable signal. When it is at a high level, the circuit system enters BUCK mode, BUCK LOGIC starts working, and generates control signals BUCK_TG and BUCK_BG. FB is the feedback voltage input, which is used to adjust the output voltage. The LevelShift circuit converts the signal in the VDD voltage domain to the VDD1 voltage domain, converts the signals LS_EN, LDO_EN, and BUCK_EN to SEL_LS, SEL_LDO, and SEL_BUCK, and the signals SEL_LS_N, SEL_LDO_N, and SEL_BUCK_N are inverted signals of SEL_LS, SEL_LDO, and SEL_BUCK. Transmission tubes TG1, TG2, TG3, TG4, and TG5 constitute a gating circuit. Transmission tubes TG1, TG2, TG3, TG4, and TG5 are connected via wires. The control signals of TG1 are SEL_LS and SEL_LS_N. When SEL_LS is high and SEL_LS_N is low, the transmission tube TG1 circuit is turned on. When SEL_LS is low and SEL_LS_N is high, the transmission tube TG1 circuit is turned off. The control signals of TG2 are SEL_LDO and SEL_LDO_N. When SEL_LDO is high and SEL_LDO_N is low, the transmission tube TG2 circuit is turned on. When SEL_LDO is low and SEL_LDO_N is high, the transmission tube TG2 circuit is turned on. The circuit of transmission tube TG2 is turned off; the control signals of TG3 and TG4 are SEL_BUCK and SEL_BUCK_N. When SEL_BUCK is high and SEL_BUCK_N is low, the circuits of transmission tubes TG3 and TG4 are turned on; when SEL_BUCK is low and SEL_BUCK_N is high, the circuits of transmission tubes TG3 and TG4 are turned off; the control signals of TG5 are SEL_LS_LDO and SEL_LS_LDO_N. When SEL_LS_LDO is high and SEL_LS_LDO_N is low, the circuit of transmission tube TG5 is turned on; when SEL_LS_LDO is low and SEL_LS_LDO_N is high, the circuit of transmission tube TG5 is turned off.U4, U5, and U6 are the third voltage comparison circuit. U4, U5, and U6 are connected by mirror wires. VON is the output voltage, which is equal to VOUT. PVIN is the input voltage. When 0.1*VON>0.105*PVIN, U4 outputs OV as a high level, indicating that the output voltage is abnormally over-voltage; when 0.1*VON>0.095*PVIN, U5 outputs OUT1 as a high level, indicating that the output voltage reaches more than 95% of the input voltage; U7 is an inverting circuit, and the output is OUT1_N. When 0.1*VON>0.08*PVIN, U6 outputs OUT2 as a high level, indicating that the output voltage reaches more than 80% of the input voltage; U8 is an inverting circuit, and the output is OUT2_N. The logic control module includes an OR-NO logic circuit U9, and an AND logic circuit U10, U11, U12, U13, U14, U15, U16, or a logic circuit U17, U18. The non-logic circuit U9, and the AND logic circuit U10, U11, U12, U13, U14, U15, U16, or the logic circuit U17, U18 are connected via wires. The logic function performed by the module is shown. Figure 4 In Load Switch mode, LS_EN and SEL_LS_LDO are high level, in LDO mode, LDO_EN and SEL_LS_LDO are high level, and in BUCK mode, BUCK_EN is high level.

[0019] Through the above, the present invention mainly utilizes the respective technical characteristics of LDO, BUCK and Load Switch to perform complementary hybrid design, has better adaptability, judges the appropriate power mode by real-time detection of output voltage and load current, and then automatically switches to the corresponding control circuit through internal logic. It can be dynamically switched according to the load (output voltage and current to load) conditions, has a wide output range and optimal efficiency, greatly expands the use scope of a single power management chip, and realizes the expansion of application scenarios and optimization of efficiency.

[0020] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claim involved.

[0021] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A LDO, BUCK and Load Switch adaptive hybrid power management method, characterized in that: The output voltage and load current are detected in real time to determine the appropriate power mode, and then the internal logic is automatically switched to the corresponding control circuit to achieve the expansion of the application scenario of the power load and the optimization of efficiency. The LDO module, Charge Pump module, LoadSwitch LOGIC module, LDO LOGIC module, BUCKLOGIC module, Level Shift module, logic control module, signal gating module, power tube, current source, current mirror circuit, and voltage comparison circuit are used as devices adapted to the hybrid power management method; the current mirror circuit has two paths and the voltage comparison circuit has three paths; the LDO module, Charge Pump module, Load Switch LOGIC module, LDO LOGIC module, BUCKLOGIC module, Level Shift module, logic control module, signal gating module, power tube, current source, current mirror circuit, and voltage comparison circuit are connected through wires; the power output end of the power tube is electrically connected to the power input end of the power load; the LDO module is used to provide power for the overall device to work, and the Charge Pump module is used to boost the power supply voltage to provide the voltage required for turning on the power tube; the Load Switch LOGIC module, LDO The LOGIC module and the BUCK LOGIC module are used to provide logic functions in corresponding working modes; the Level Shift module is used to convert low-voltage domain signals into high-voltage domain signals, and the logic control module is used to select the corresponding working mode according to the corresponding criteria; the signal selection module is used to select the corresponding working channel, and the power tube is used to provide a charging and discharging channel; the current source is used to provide a reference current, the current mirror circuit is used to copy the current in proportion, and the comparison circuit is used to compare the voltage.

2. The LDO, BUCK and Load Switch adaptive hybrid power management method according to claim 1, characterized in that: There are two power tubes, and the two power tubes are connected by wires.

3. The LDO, BUCK and Load Switch adaptive hybrid power management method according to claim 1, characterized in that: The first current mirror circuit is composed of two MOS tubes, which are connected via wires. The second current mirror circuit is composed of three MOS tubes and three resistors, which are connected via wires.

4. The LDO, BUCK and Load Switch adaptive hybrid power management method according to claim 1, characterized in that: The signal selection module is composed of five transmission tubes, and the five transmission tubes are connected by wires.

5. The LDO, BUCK and Load Switch adaptive hybrid power management method according to claim 1, characterized in that: The third voltage comparison circuit is composed of three comparator modules, and the three comparator modules are connected via wires.

6. The LDO, BUCK and Load Switch adaptive hybrid power management method according to claim 1, characterized in that: The logic function module comprises ten logic gate module circuits, and the ten logic gate module circuits are connected via wires.

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