Power conditioning circuit, adjustable power supply system and method

Abstract

This invention provides a power adjustment circuit, an adjustable power supply system, and a method thereof. The adjustable power supply system includes a power module, a device power supply unit, and a control circuit. The device power supply unit operates according to its operating voltage and provides power to a device under test (DUT). The control circuit outputs an adjustment signal to the power module based on the power consumption of the DUT. The power module generates an operating voltage based on the adjustment signal and ensures that the initial power consumption generated by the device power supply unit is less than a preset power. Therefore, this invention enables the device power supply unit to provide high voltage and high current output to the DUT.

Description

Technical Field

[0001] This invention relates to a power supply device, and more particularly to a power adjustment circuit, an adjustable power supply system, and a method thereof. Background Technology

[0002] Please see Figure 1 This is a power supply diagram for the device under test. Figure 1 Most existing device power supplies (DPS) 10 can withstand a maximum power consumption of approximately 10W. However, to meet the high current requirements of the device under test (DUT) 12, the operating voltage VDD of the DPS 10 can be set to 10V, enabling it to stably provide a supply voltage of -1V to 7V and a supply current of 0.7A to the DUT 12. Although the DPS 10 can withstand a certain power consumption, its temperature will rise as the power consumption increases. Therefore, a heat dissipation structure is necessary to cool the DPS 10.

[0003] However, with the increasing demand for high current from the device under test (DUT) 12, for example, the device power supply 10 provides a supply current of 1A to the DUT 12, and the supply voltage provided by the device power supply 10 to the DUT 12 is reduced to 0V to 3.7V so that the device power supply 10 can be effectively cooled by the existing heat dissipation structure. However, due to the limitations of the heat dissipation structure, the existing device power supply 10 obviously cannot simultaneously meet the high voltage or high current requirements of different DUTs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a power adjustment circuit, an adjustable power supply system and method that can automatically control the power supply status of the device power supply according to the power consumption status of the device under test.

[0005] This invention provides an adjustable power supply system, including a power module, a device power supply unit, and a control circuit. The device power supply unit is electrically connected to the power module and operates according to the working voltage, providing power to a device under test (DUT). The control circuit outputs an adjustment signal according to the power consumption of the DUT, causing the power module to generate a working voltage based on the adjustment signal, and ensuring that the first power consumption generated by the device power supply unit is less than a preset power.

[0006] This invention provides a power adjustment circuit suitable for power control of a power module and a device power supply. The power module provides an operating voltage to the device power supply, which then operates according to the operating voltage and provides power to a device under test. The power adjustment circuit includes a detection circuit and a control circuit. The detection circuit detects the power consumption of the device under test and outputs a power detection result. The control circuit is electrically connected to the detection circuit and outputs an adjustment signal based on the power detection result to control the power module, causing the power module to generate an operating voltage according to the adjustment signal and ensuring that a first power consumption generated by the device power supply is less than a preset power. The control circuit calculates a second power consumption of the device under test and the first power consumption of the device power supply based on the power detection result. When the first power consumption is greater than the preset power, the control circuit outputs an adjustment signal.

[0007] This invention provides an adjustable power supply method, which uses a control circuit to control the power supply of a power module and a device power supply. The method includes detecting the power consumption of the device under test when the device power supply provides power to the device under test, wherein the device power supply performs power supply operation according to the operating voltage provided by the power module; and the control circuit outputs an adjustment signal according to the detection result, so that the power module generates an operating voltage according to the adjustment signal, and the first power consumption generated by the device power supply is less than a preset power.

[0008] In summary, the power adjustment circuit, adjustable power supply system and method provided in the embodiments of the present invention can automatically adjust the power consumption of the device power supply according to the power consumption status of the device under test, so that the device power supply can stably provide high voltage and high current to meet the power needs of different devices under test, and can effectively reduce the heat dissipation burden.

[0009] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention. Attached Figure Description

[0010] Figure 1 A schematic diagram of the power supply for the device under test.

[0011] Figure 2 A functional block diagram of an adjustable power supply system is provided for embodiments of the present invention.

[0012] Figure 3 A flowchart is provided for an adjustable power supply method according to an embodiment of the present invention.

[0013] Figure 4 A functional block diagram of an adjustable power supply system is provided for embodiments of the present invention.

[0014] Figure 5 A flowchart is provided for an adjustable power supply method according to an embodiment of the present invention. Detailed Implementation

[0015] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content provided in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Furthermore, the accompanying drawings of the present invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the content provided is not intended to limit the scope of protection of the present invention.

[0016] It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein should be interpreted to include, as appropriate, any combination of one or more of the related listed items.

[0017] This invention provides a power adjustment circuit, an adjustable power supply system, and a method thereof. By detecting the power consumption at the load end, the power consumption of the device power supply (DPS) currently supplied to the load end can be determined based on the detection results. An adjustment mechanism can be actively used to reduce the power consumption of the device power supply, thereby stabilizing the operation of the device power supply, reducing the heat dissipation burden, and enabling the device power supply to provide high voltage and high current output to meet the power requirements of various devices under test.

[0018] [Example of an Adjustable Power Supply System]

[0019] Please refer to the following respectively Figure 2 , Figure 2This is a functional block diagram of an adjustable power supply system provided in an embodiment of the present invention. The adjustable power supply system 2 described in this embodiment includes, but is not limited to, a power module 20, a device power supply 22, a control circuit 24, and a detection circuit 26. The power supply object of the adjustable power supply system 2 described herein is illustrated using a device under test (DUT) in a test system as an example, but is not limited thereto. The power module 20 is electrically connected to the device power supply 22, the device power supply 22 is electrically connected to the DUT 3, the detection circuit 26 is electrically connected to the DUT 3, and the control circuit 24 is electrically connected to the detection circuit 26 and the power module 20.

[0020] Furthermore, the power module 20 can provide an operating voltage VDD to the device power supply 22, which then operates based on this operating voltage VDD. The device power supply 22 can provide different power supplies according to the power requirements of different devices under test 3. For example, the power supply provided by the device power supply 22 can provide different supply voltages Vo or supply currents Io to the device under test 3 according to settings or operation. The specific power supply architecture of the device power supply 22 is well known to those skilled in the art and will not be described in detail here.

[0021] The control circuit 24 outputs an adjustment signal to the power module 20 based on the power consumption of the device under test (DUT) 3. This adjustment signal is used to adjust the operating voltage VDD of the power module 20 to the device power supply 22. For example, assuming the power consumption of the device power supply 22 is the first power consumption and the power consumption of the DUT 3 is the second power consumption, the sum of the first and second power consumption equals the total power consumption, which is the operating voltage of the device power supply 22 multiplied by VDD and the supply current Io provided by the device power supply 22 to the DUT 3. Therefore, when the total power consumption is a fixed value, when the second power consumption decreases, i.e., when the DUT 3 is under light load, the first power consumption increases relatively. However, excessive first power consumption may cause the device power supply 22 to heat up too quickly or exceed its power tolerance, resulting in unstable operation. Therefore, in this embodiment, the control circuit 24 mainly adjusts the power consumption of the device power supply 22 to a reasonable and safe range below a preset power through the adjustment signal. The preset power is, for example, the power that allows the device power supply 22 to operate stably, but this invention is not limited to this.

[0022] Specifically, when the control circuit 24 determines, based on the power consumption of the device under test 3, that the power consumption of the device power supply 22 is greater than the preset power, the control circuit 24 outputs an adjustment signal to the power module 20. This causes the power module 20 to adjust the operating voltage VDD supplied to the device power supply 22 accordingly, thereby ensuring that the adjusted operating voltage VDD makes the power consumption of the device power supply 22 less than the preset power. Conversely, when the control circuit 24 determines, based on the power consumption of the device under test 3, that the power consumption of the device power supply 22 is less than the preset power, the control circuit 24 will not output an adjustment signal; that is, the device power supply 22 can operate normally in this state.

[0023] In one embodiment, the control circuit 24 can determine the power consumption status of the device under test (DUT) 3 through the detection circuit 26. Here, the power consumption status refers to the power consumption, voltage, or current of the DUT 3 itself. For example, the control circuit 24 can determine the power supply to the DUT 3 through the detection circuit 26, and then calculate the power consumption of the DUT 3 based on this power supply. The detection circuit 26 can be, for example, various combinations of voltage detectors or current detectors.

[0024] For example, control circuit 24 may determine the power supply to device under test 3 in several ways. When control circuit 24 knows the supply current Io provided by device power supply 22 to device under test 3, control circuit 24 can detect the supply voltage Vo provided by device power supply 22 to device under test 3 through the voltage detector in detection circuit 26. Alternatively, when control circuit 24 knows the supply voltage Vo provided by device power supply 22 to device under test 3, control circuit 24 can detect the supply current Io provided by device power supply 22 to device under test 3 through the current detector in detection circuit 26. Alternatively, control circuit 24 can detect the supply voltage Vo and supply current Io provided by device power supply 22 to device under test 3 through both the voltage detector and current detector in detection circuit 26. Finally, control circuit 24 can determine the power consumption of device under test 3 based on the product of supply voltage Vo and supply current Io.

[0025] Therefore, once the control circuit 24 receives the power supply detection result of the device under test 3, it can calculate the first power consumption of the power supply 22 and the second power consumption of the device under test 3. The first power consumption is calculated, for example, by subtracting the supply voltage Vo provided by the power supply 22 to the device under test 3 from the operating voltage VDD supplied to the power supply 22, obtaining a voltage difference. This voltage difference is then multiplied by the supply current Io provided by the power supply 22 to the device under test 3 to obtain the first power consumption. In practice, this operating voltage VDD is greater than the supply voltage Vo. The second power consumption is calculated, for example, by multiplying the supply voltage Vo provided by the power supply 22 to the device under test 3 by the supply current Io. The calculation of the first and second power consumption in this invention is not limited to the examples described above.

[0026] In another embodiment, the control circuit 24 and the detection circuit 26 can be used as the power adjustment circuit for the power module 20 and the device power supply 22. The control circuit 24 adjusts the power supplied by the power module 20 to the device power supply 22 based on the detection result of the detection circuit 26, so that the power consumption of the device power supply 22 can be maintained within a preset power that can be used normally according to the power consumption of the device under test 3.

[0027] [Example of Adjustable Power Supply Method]

[0028] Please refer to Figure 3 . Figure 3 This is a flowchart of an adjustable power supply method according to an embodiment of the present invention. Figure 3 The flowchart shown is based on Figure 2 The architecture is illustrated by example, but is not limited to this. Figure 3 The process shown includes the following steps.

[0029] In step S301, the device under test 3 is detected. Here, the control circuit 24 controls the detection circuit 26 to detect the power consumption status of the device under test 3, so as to know the supply voltage Vo or supply current provided by the device power supply 22 to the device under test 3.

[0030] In step S303, the power consumption of the device under test 3 is calculated. The control circuit 24 can calculate the current power consumption of the device under test 3 based on the detection result of step S301.

[0031] In step S305, it is determined whether the power consumption of the device power supply 22 is less than the preset power. After the control circuit 24 knows the power consumption status of the device under test 3, it can further calculate the power consumption of the device power supply 22 based on the power consumption of the device under test, and compare the power consumption of the device power supply 22 with the preset power to determine whether the power consumption of the device power supply 22 is less than the preset power.

[0032] In step S307, an adjustment signal is output. If step S305 determines "no," it means that the power consumption of the device power supply 22 is greater than the preset power. At this time, the control circuit 24 outputs an adjustment signal to the power module 20, so that the power module 20 can adjust the operating voltage VDD supplied to the device power supply 22 according to this adjustment signal. The adjustment method is, for example, to increase or decrease the operating voltage, so that the power consumption of the device power supply 22 at the adjusted operating voltage VDD is less than the preset power. If step S305 determines "yes," then the process returns to step S301 to continue execution.

[0033] As described in the above embodiments, the control circuit 24 can determine whether the power consumption of the device power supply 22 is less than the preset power based on the detection result of the detection circuit 26. When the power consumption of the device power supply 22 is greater than the preset power, the control circuit 24 will output an adjustment signal to reduce the power consumption of the device power supply 22 to less than the preset power through the power module 20.

[0034] It is worth noting that, in another embodiment, the control circuit 24 can also adjust the power consumption of the device power supply 22 by looking up a table. An example is given below.

[0035] The table below shows the correspondence between the detection voltage Vd and the operating voltage VDD. The detection voltage Vd is the detection result of the detection circuit 26 detecting the supply voltage Vo of the device under test 3. The operating voltage VDD is the voltage used by the device power supply 22. It is also assumed that the device power supply 22 provides a fixed 1.2A as the supply current Io to the device under test 3.

[0036] Vd 0V 1V 2V 3V 4V 5V 6V 7V VDD 3V 4V 5V 6V 7V 8V 9V 10V Vd 8V 9V 10V 11V 12V 13V 14V 15V VDD 11V 12V 13V 14V 15V 16V 17V 18V

[0037] Table 1

[0038] In Table 1 above, when Vd is 0V, the corresponding VDD is 3V; when Vd is 1V, the corresponding VDD is 4V... and when Vd is 15V, the corresponding VDD is 18V. This Table 1 can be stored in the control circuit 24 for lookup purposes.

[0039] For example, when the control circuit 24 detects that the detection voltage Vd is 0V through the detection circuit 26, the control circuit 24 outputs an adjustment signal to the power module 20 after looking up the table. This adjustment signal is used to control the power module 20 to adjust the supply voltage VDD to the device power supply unit 22 to 3V.

[0040] When the control circuit 24 detects that the detection voltage Vd is 1V through the detection circuit 26, the control circuit 24 outputs an adjustment signal to the power module 20 after looking up the table. This adjustment signal is used to control the power module 20 to adjust the supply voltage VDD to the device power supply unit 22 to 4V.

[0041] The detection results for other detection voltages Vd are deduced in the same way. In other words, the control circuit 24 can effectively control the power consumption of the device power supply 22 to be less than the preset power by looking up a table. This preset power is, for example, 3W. At the same time, with the heat dissipation design on the device power supply 22, the device power supply 22 can work normally and stably when meeting the requirements of high voltage and high current output.

[0042] Therefore, according to the design method in Table 1, when the supply voltage provided by the power supply unit 22 to the device under test 3 changes from a first supply voltage to a second supply voltage, the corresponding adjustment signal output by the control circuit 24 is to control the operating voltage provided by the power module 20 to the power supply unit 24 to change from a first operating voltage to a second operating voltage. And when the supply voltage provided by the power supply unit 22 to the device under test 3 changes from a second supply voltage to a first supply voltage, the corresponding adjustment signal output by the control circuit 24 is to control the operating voltage provided by the power module 20 to the power supply unit 22 to change from a second operating voltage to a first operating voltage. The second supply voltage is greater than the first supply voltage, and the second operating voltage is greater than the first operating voltage. Furthermore, the difference between the first supply voltage and the first operating voltage is the same as the difference between the second supply voltage and the second operating voltage. Table 1 is used here to illustrate how the control circuit 24 controls the operating voltage VDD output by the power module 20 by looking up the table. However, the voltages in Table 1 are merely illustrative examples, and the present invention is not limited thereto.

[0043] [Another embodiment of an adjustable power supply system with temperature detection]

[0044] Please refer to Figure 4 . Figure 4 A functional block diagram of an adjustable power supply system is provided for embodiments of the present invention. Figure 4 The adjustable power supply system 4 shown is compared to Figure 2The adjustable power supply system 2 shown is further equipped with a temperature detector 28. The temperature detector 28 will be described here, while the operation of the other components can be referred to the above description.

[0045] Temperature detector 28 is electrically connected to device power supply 22 and control circuit 24. Temperature detector 28 is used to detect the operating temperature of device power supply 22 and outputs a temperature detection result to control circuit 24. When control circuit 24 receives the temperature detection result from temperature detector 28, control circuit 24 can know the operating temperature of device power supply 22 and further determine whether the operating temperature of device power supply 22 exceeds the default temperature.

[0046] When the operating temperature of the device power supply 22 exceeds the default temperature, the control circuit 24 performs a cooling operation on the device power supply 22 through the power module 20. For example, the control circuit 24 can control the power module 20 to reduce the operating voltage output to the device power supply 22, thereby achieving a cooling effect when the operating voltage of the device power supply 22 is reduced. The method of reducing the operating voltage described here is, for example, reducing it by 1V each time, but the present invention is not limited to this.

[0047] [Another embodiment of the adjustable power supply method]

[0048] Please refer to Figure 5 . Figure 5 This is a flowchart of an adjustable power supply method according to an embodiment of the present invention. Figure 5 The flowchart shown is based on Figure 4 The architecture is illustrated by example, but is not limited to this. Figure 5 The process shown includes the following steps.

[0049] In step S501, the device under test 3 is tested.

[0050] In step S503, the power consumption of the device under test 3 is calculated.

[0051] In step S505, it is determined whether the power consumption of the device power supply 22 is less than the preset power.

[0052] In step S507, an adjustment signal is output. If step S505 determines no, the control circuit 24 outputs an adjustment signal to the power module 20, which then adjusts the operating voltage supplied to the device power supply 22 according to this signal. If step S505 determines yes, then step S509 is executed.

[0053] In step S509, the temperature of the device power supply 22 is detected. The control circuit 24 detects the temperature of the device power supply 22 via the temperature detector 28.

[0054] In step S511, it is determined whether the operating temperature of the device power supply 22 is lower than the default temperature. Based on the detection result of step S509, the control circuit 24 can determine the operating temperature of the device power supply 22 and compare this operating temperature with the default temperature.

[0055] In step S513, the operating voltage is reduced. If step S511 determines no, it means that the current operating temperature of the device power supply 22 exceeds the default temperature. Therefore, the control circuit 24 will perform a cooling operation on the device power supply 22. For example, the control circuit 24 controls the power module 20 to reduce the operating voltage VDDD, so that the operating temperature of the device power supply 22 can be reduced accordingly.

[0056] If step S511 is determined to be yes, then step S501 is executed.

[0057] In one embodiment, the control circuit 101 may be one or any combination of an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a system-on-a-chip (SOC), and may work with other related circuit components and firmware to achieve the above-described functional operation.

[0058] [Beneficial Effects of the Examples]

[0059] The adjustable power supply system and method provided by this invention actively detects the power consumption of the device under test and adjusts the operating voltage of the power module accordingly, so that the power consumption of the device power supply itself can be controlled within a preset power. This allows the device power supply to provide high voltage output, high current output or other power outputs according to the power needs of different devices under test, and can ensure that the device power supply can work stably and normally, and also reduce the heat dissipation burden.

[0060] The above-described content is merely a preferred embodiment of the present invention and is not intended to limit the scope of the claims of the present invention. Therefore, any equivalent technical changes made based on the description and drawings of the present invention are included within the scope of the claims of the present invention.

Claims

1. An adjustable power supply system, characterized in that, include: A power module provides a working voltage; A device power supply is electrically connected to the power module and performs power supply operation according to the operating voltage, and provides a power supply to a device under test; as well as A control circuit outputs an adjustment signal to control the power supply module according to the power consumption status of the device under test, so that the power supply module adjusts the operating voltage according to the adjustment signal, and makes the first power consumption generated by the power supply of the device according to the adjusted operating voltage less than a preset power. The control circuit calculates the second power consumption of the device under test and the first power consumption of the device's power supply based on the power consumption status. When the first power consumption is greater than the preset power, the control circuit outputs the adjustment signal.

2. The adjustable power supply system as described in claim 1, characterized in that, It also includes a detection circuit that is electrically connected to the control circuit. The detection circuit detects the power consumption of the device under test and outputs a power detection result to the control circuit.

3. The adjustable power supply system as described in claim 2, characterized in that, The detection circuit is either a voltage detector or a current detector.

4. The adjustable power supply system as described in claim 2, characterized in that, The adjustment signal is used to increase or decrease the operating voltage of the power supply module for the device power supply so that the first power consumption is less than the preset power. The power supply provided by the device power supply includes a supply voltage and a supply current.

5. The adjustable power supply system as described in claim 4, characterized in that, When the power supply of the device provides a fixed supply current to the device under test, when the supply voltage provided by the power supply to the device under test changes from a first supply voltage to a second supply voltage, the adjustment signal output by the control circuit controls the operating voltage provided by the power module to the power supply to change from a first operating voltage to a second operating voltage. When the supply voltage provided by the power supply to the device under test changes from the second supply voltage to the first supply voltage, the adjustment signal output by the control circuit controls the operating voltage provided by the power module to the power supply to change from the second operating voltage to the first operating voltage, wherein the second supply voltage is greater than the first supply voltage and the second operating voltage is greater than the first operating voltage.

6. The adjustable power supply system as described in claim 5, characterized in that, The difference between the first supply voltage and the first operating voltage is the same as the difference between the second supply voltage and the second operating voltage.

7. The adjustable power supply system as described in claim 1, characterized in that, It also includes a temperature detector electrically connected to the control circuit, which controls the power module to reduce the operating voltage when the temperature detector detects that the temperature of the device's power supply exceeds a default temperature.

8. A power regulation circuit, suitable for power control of a power module and a device power supply, wherein the power module provides an operating voltage to the device power supply, and the device power supply performs power supply operation according to the operating voltage and provides power to a device under test, characterized in that, include: A detection circuit detects the power consumption of the device under test and outputs a power detection result; as well as A control circuit is electrically connected to the detection circuit. Based on the power detection result, it outputs an adjustment signal to control the power module, so that the power module adjusts the working voltage according to the adjustment signal, and makes the first power consumption generated by the power supply of the device based on the adjusted working voltage less than a preset power. The control circuit calculates the second power consumption of the device under test and the first power consumption of the device's power supply based on the power detection result. When the first power consumption is greater than the preset power, the control circuit outputs the adjustment signal.

9. The power adjustment circuit as described in claim 8, characterized in that, The adjustment signal is used to increase or decrease the operating voltage of the power supply module that supplies power to the device, so that the first power consumption is less than the preset power.

10. The power adjustment circuit as described in claim 8, characterized in that, It also includes a temperature detector electrically connected to the control circuit, which controls the power module to reduce the operating voltage when the temperature detector detects that the temperature of the device's power supply exceeds a default temperature.

11. An adjustable power supply method, applicable to a control circuit for power control of a power module and a device power supply, characterized in that, include: When the power supply of the device provides power to a device under test (DUT), the control circuit detects the power consumption status of the DUT, wherein the power supply operates according to a working voltage provided by the power module; and The control circuit outputs an adjustment signal based on the detection result to control the power module, so that the power module adjusts the working voltage according to the adjustment signal, and the power supply of the device generates a first power consumption less than a preset power based on the adjusted working voltage. The control circuit calculates the second power consumption of the device under test and the first power consumption of the device's power supply based on the power consumption status. When the first power consumption is greater than the preset power, the control circuit outputs the adjustment signal.

12. The adjustable power supply method as described in claim 11, characterized in that, The adjustment signal is used to increase or decrease the operating voltage of the power supply module to the device power supply, so that the first power consumption is less than the preset power. The power supply provided by the device power supply includes a supply voltage and a supply current.

13. The adjustable power supply method as described in claim 12, characterized in that, When the power supply of the device provides a fixed supply current to the device under test, when the supply voltage provided by the power supply to the device under test changes from a first supply voltage to a second supply voltage, the adjustment signal output by the control circuit controls the operating voltage provided by the power module to the power supply to change from a first operating voltage to a second operating voltage. When the supply voltage provided by the power supply to the device under test changes from the second supply voltage to the first supply voltage, the adjustment signal output by the control circuit controls the operating voltage provided by the power module to the power supply to change from the second operating voltage to the first operating voltage, wherein the second supply voltage is greater than the first supply voltage and the second operating voltage is greater than the first operating voltage.

14. The adjustable power supply method as described in claim 13, characterized in that, The difference between the first supply voltage and the first operating voltage is the same as the difference between the second supply voltage and the second operating voltage.

15. The adjustable power supply method as described in claim 11, characterized in that, Also includes: Detect the temperature of the device's power supply; When the temperature of the power supply unit exceeds a default temperature, the control circuit controls the power module to reduce the operating voltage.

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