Driving voltage adjusting circuit and power supply system
By sensing the temperature of the voltage converter switching element and dynamically adjusting the driving voltage, the power loss problem of the DC-DC voltage converter at different loads and temperatures is solved, achieving more efficient energy conversion and cost savings.
Patent Information
- Application Number
- CN202510438697.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-08
- Publication Date
- 2025-07-11
AI Technical Summary
Existing DC-DC voltage converters have high power loss under different load and temperature conditions, especially the losses caused by changes in internal resistance of switching elements are difficult to effectively manage.
The temperature of the switching element of the voltage converter is sensed by the sensing unit, and the driving voltage is dynamically adjusted by the voltage divider and adjustment unit to match the temperature changes of the switching element and reduce power loss.
It effectively reduces the power loss of the voltage converter, improves the conversion efficiency, and saves the cost of the heat dissipation element.
Smart Images
Figure CN120301166A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a driving voltage adjustment circuit and a power supply system, and more particularly to a driving voltage adjustment circuit and a power supply system for a voltage converter. Background Art
[0002] In existing DC-DC voltage converters, when the load is light, the main power loss is the switching of the switching elements of the voltage converter. When the load is heavy, the main power loss is the conduction loss of the switching elements. Since the internal resistance of the switching elements varies with the driving voltage, the power loss of the voltage converter can be effectively reduced by appropriately adjusting the driving voltage of the switching elements of the voltage converter.
[0003] In addition, since the impedance of the switching elements of the voltage converter changes with temperature, the power loss of the voltage converter is also positively correlated with temperature. In view of this, developing a driving voltage adjustment circuit and a power supply system that can adjust the driving voltage according to the temperature of the switching elements has become an objective worthy of research and development for relevant industries. Summary of the Invention
[0004] Therefore, an object of the present invention is to provide a driving voltage adjustment circuit and a power supply system that sense the temperature of the switching elements of a voltage converter through a sensing unit to adjust the driving voltage of the voltage converter. Thus, the driving voltage adjustment circuit and the power supply system of the present invention can adjust the driving voltage according to the temperature of the voltage converter, thereby reducing power loss.
[0005] According to an embodiment of the structural aspect of the present invention, a driving voltage adjustment circuit is provided, including a sensing unit, a voltage dividing unit, and an adjustment unit. The sensing unit is disposed around a switching element of a voltage converter and is used to sense a temperature of the switching element of the voltage converter. The voltage dividing unit is electrically connected to the sensing unit and the voltage converter and receives a driving voltage. The voltage dividing unit divides the driving voltage according to the temperature of the switching element to generate a divided voltage. The adjustment unit is electrically connected to the voltage dividing unit and receives an input voltage and the divided voltage. The adjustment unit adjusts the input voltage according to the divided voltage and outputs a driving voltage, and the driving voltage is transmitted to the voltage converter. The temperature is positively correlated with the driving voltage.
[0006] Another embodiment according to the structural aspect of the present invention provides a power supply system, including a voltage converter and a driving voltage adjustment circuit. The voltage converter is driven by a driving voltage and includes a switching element group. The switching element group includes two switching elements. The driving voltage adjustment circuit includes a sensing unit, a voltage dividing unit, and an adjustment unit. The sensing unit is disposed around one of the two switching elements and is used to sense a temperature of this one of the two switching elements. The voltage dividing unit is electrically connected to the sensing unit and the voltage converter and receives the driving voltage. The voltage dividing unit divides the driving voltage according to the temperature of this one of the two switching elements to generate a divided voltage. The adjustment unit is electrically connected to the voltage dividing unit and receives an input voltage and the divided voltage. The adjustment unit adjusts the input voltage according to the divided voltage to output the driving voltage, and the driving voltage is transmitted to the voltage converter. The temperature is positively correlated with the driving voltage. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 FIG. is a block diagram showing the driving voltage adjustment circuit according to the first embodiment of the present invention;
[0008] Figure 2 FIG. shows the connection according to Figure 1 the circuit diagram of the voltage converter of the driving voltage adjustment circuit;
[0009] Figure 3 FIG. shows the connection according to Figure 2 the voltage diagram of the voltage converter of the driving voltage adjustment circuit;
[0010] Figure 4 FIG. is a schematic diagram showing the driving voltage adjustment circuit according to the second embodiment of the present invention;
[0011] Figure 5 FIG. is a schematic diagram showing the driving voltage adjustment circuit according to the third embodiment of the present invention;
[0012] Figure 6 FIG. is a schematic diagram showing the power supply system according to the fourth embodiment of the present invention; and
[0013] Figure 7 FIG. shows the connection according to Figure 6 the circuit diagram of the power supply system;
[0014] Among them, the reference numerals are explained as follows:
[0015] 10, 20: voltage converter
[0016] 11: pulse generation circuit
[0017] 100, 100a, 100b: driving voltage adjustment circuit
[0018] 120, 220: sensing unit
[0019] 130, 230: Voltage dividing unit
[0020] 140, 140a, 140b, 240: Adjusting unit
[0021] 141: Power amplifier
[0022] 142: Pulse width modulation controller
[0023] 200: Power supply system
[0024] BST, LX: Endpoints
[0025] C: Capacitor
[0026] L: Inductor
[0027] RD1, RD2: Resistors
[0028] RL: Load
[0029] GND, Vin, VLX, Vout: Voltages
[0030] Sco: Comparison signal
[0031] Ta, Tb, T1, T2: Switching elements
[0032] VBST (max) : Maximum value
[0033] VBST (min) : Minimum value
[0034] Vdi: Divided voltage
[0035] Vdr: Driving voltage
[0036] Vi: Input voltage
[0037] Vref: Reference voltage Detailed implementation manners
[0038] Please refer to Figure 1 and Figure 2 , Figure 1 is a block diagram showing a driving voltage adjustment circuit 100 according to the first embodiment of the present invention, Figure 2 is a circuit diagram showing a voltage converter 10 connected to the driving voltage adjustment circuit 100 according to Figure 1 . The driving voltage adjustment circuit 100 includes a sensing unit 120, a voltage dividing unit 130, and an adjusting unit 140. The sensing unit 120 is disposed on a switching element (i.e., Figure 2around one of the switching elements Ta and Tb, and is used to sense the temperature of one of the switching elements Ta and Tb of the voltage converter 10. The voltage dividing unit 130 is electrically connected to the sensing unit 120 and the voltage converter 10, and receives a driving voltage Vdr. The voltage dividing unit 130 divides the driving voltage Vdr according to the temperature of the switching elements Ta and Tb to generate a divided voltage Vdi. The adjusting unit 140 is electrically connected to the voltage dividing unit 130, and receives an input voltage Vi and the divided voltage Vdi. The adjusting unit 140 adjusts the input voltage Vi according to the divided voltage Vdi and outputs the driving voltage Vdr, and the driving voltage Vdr is transmitted to the voltage converter 10. The temperature is positively correlated with the driving voltage Vdr.
[0039] Specifically, the sensing unit 120 can be a thermistor with a negative temperature coefficient, the voltage dividing unit 130 can be a voltage dividing circuit composed of resistors in series, and the adjusting unit 140 can be a DC-DC converter or a low dropout regulator (LDO), but the present invention is not limited thereto.
[0040] In Figure 2 , the voltage converter 10 can be a DC-DC converter, which includes a pulse generating circuit 11, two switching elements Ta and Tb, a capacitor C, an inductor L, and a load RL. The pulse generating circuit 11 is used to input a pulse to the switching elements Ta and Tb. The switching elements Ta and Tb are driven by the driving voltage Vdr and alternately switch on according to the voltage level of the pulse. The switching elements Ta and Tb can be metal-oxide-semiconductor field-effect transistors (MOSFETs), and the resistance value of their internal resistance becomes smaller as the driving voltage Vdr of the gate rises. The voltage Vout is the output voltage of the voltage converter 10.
[0041] Please refer to Figure 2 and Figure 3 , Figure 3 is a voltage schematic diagram of the voltage converter 10 connected to the driving voltage adjustment circuit 100 according to Figure 2 . Among them, the ground voltage GND, the voltage VLX at the end point LX, the voltage range interval at the end point BST, and the voltage Vin in the voltage converter 10 shown in Figure 2 are shown. The end point BST is connected to the drain of the switching element Ta, and the end point LX is connected to the source of the switching element Ta and the drain of the switching element Tb. The voltage VLX at the end point LX is the same as the voltage Vin, and the voltage at the end point BST is the voltage Vin plus the driving voltage Vdr. When the driving voltage Vdr changes with temperature, the voltage at the end point BST is between the maximum value VBST (max) and the minimum value VBST(min) Between them, the voltage difference between the voltage of the end point BST and the voltage VLX is also variable.
[0042] Furthermore, during the operation of the voltage converter 10, the switching elements Ta and Tb are alternately turned on and generate heat loss. When the temperatures of the switching elements Ta and Tb in the voltage converter 10 rise, the sensing unit 120 senses the temperature of one of the switching elements Ta and Tb, and divides the driving voltage Vdr through the voltage dividing unit 130 according to the temperature, and adjusts the driving voltage Vdr to the adjusted driving voltage Vdr according to the aforementioned temperature through the adjustment unit 140. Thus, the driving voltage adjustment circuit 100 of the present invention dynamically adjusts the driving voltage Vdr according to the temperatures of the switching elements Ta and Tb in the voltage converter 10, and can avoid the power loss of the voltage converter 10 from rising with the temperature.
[0043] Please refer to Figure 1 and Figure 4 where Figure 4 is a schematic diagram showing the driving voltage adjustment circuit 100a of the second embodiment of the present invention. The driving voltage adjustment circuit 100a includes a sensing unit 120, a voltage dividing unit 130, and an adjustment unit 140a. In the second embodiment, the sensing unit 120 and the voltage dividing unit 130 act in the same manner as the sensing unit 120 and the voltage dividing unit 130 of the driving voltage adjustment circuit 100 of the first embodiment, and will not be described in detail. Particularly, the adjustment unit 140a is a DC-DC converter, which may include a power amplifier 141, a pulse width modulation controller 142, and a switching element group. The power amplifier 141 is electrically connected to the voltage dividing unit 130 and generates a comparison signal Sco according to the divided voltage Vdi. The pulse width modulation controller 142 is electrically connected to the power amplifier 141 and generates a pulse signal according to the comparison signal Sco. The switching element group is electrically connected to the pulse width modulation controller 142 and adjusts the input voltage Vi to output the driving voltage Vdr according to the pulse signal. The switching element group may include switching elements T1 and T2. Furthermore, the adjustment unit 140a may further include a filtering unit (not shown in the figure), and the filtering unit is electrically connected between the switching element group and the voltage converter (not shown in the figure) to reduce the noise of the driving voltage Vdr. Wherein the voltage converter may have the same structure as the Figure 2 voltage converter 10, and the filtering unit includes an inductor L and a capacitor C.
[0044] Specifically, the sensing unit 120 is a thermistor. The voltage dividing unit 130 may include two resistors RD1 and RD2, where the two resistors RD1 and RD2 are connected in series and connected in parallel with the sensing unit 120. When the sensing unit 120 senses an increase in the temperature of the switching elements Ta and Tb, the resistance value of the sensing unit 120 decreases, causing the divided voltage Vdi to decrease accordingly. The power amplifier 141 compares the divided voltage Vdi with the reference voltage Vref to generate a comparison signal Sco. The pulse width modulation controller 142 adjusts the switching frequency of the generated pulse according to the comparison signal Sco, thereby increasing the driving voltage Vdr, and inputs the adjusted driving voltage Vdr to the voltage converter.
[0045] For example, when the resistor RD1 is 12 KΩ (ohms) and the resistor RD2 is 1.8 KΩ, the driving voltage Vdr required by the voltage converter can be as shown in Table 1. It can be seen from Table 1 that when the temperature around the sensing unit 120 rises, the resistance value of the sensing unit 120 decreases, and the driving voltage Vdr generated by the adjustment unit 140a increases accordingly. Thus, the driving voltage adjustment circuit 100a of the present invention senses the temperature of the switching elements Ta and Tb with the highest temperature in the voltage converter through the sensing unit 120, and feeds back to the adjustment unit 140a according to the temperature through the voltage dividing unit 130, so as to increase the driving voltage Vdr through the adjustment unit 140a, drive the voltage converter with a higher voltage, and improve the conversion efficiency of the voltage converter.
[0046] Table 1
[0047]
[0048]
[0049] Please refer to Figure 1 and Figure 5 where Figure 5 is a schematic diagram showing the driving voltage adjustment circuit 100b of the third embodiment of the present invention. The driving voltage adjustment circuit 100b includes a sensing unit 120, a voltage dividing unit 130, and an adjustment unit 140b. In the third embodiment, the sensing unit 120 and the voltage dividing unit 130 of the driving voltage adjustment circuit 100b act in the same manner as the sensing unit 120 and the voltage dividing unit 130 of the driving voltage adjustment circuit 100 of the first embodiment, and will not be elaborated here. In particular, the adjustment unit 140b can be a linear voltage regulator, which may include a power amplifier 141 and a switching element T1. The power amplifier 141 is electrically connected to the voltage dividing unit 130 and generates a comparison signal Sco based on the divided voltage Vdi. The switching element T1 is electrically connected to the power amplifier 141 and adjusts the input voltage Vi according to the comparison signal Sco to output the driving voltage Vdr.
[0050] Furthermore, the power amplifier 141 compares the divided voltage Vdi and the reference voltage Vref to generate a comparison signal Sco, and adjusts the input voltage Vi to the driving voltage Vdr according to the comparison signal Sco. Thus, the driving voltage adjustment circuit 100b of the present invention dynamically adjusts the driving voltage Vdr according to the temperature of the voltage converter (not shown in the figure), saving the cost of the heat dissipation element in the voltage converter.
[0051] Please refer to Figure 6 and Figure 7 , Figure 6 which is a schematic diagram showing the power supply system 200 of the fourth embodiment of the present invention. Figure 7 which is a circuit schematic diagram showing the power supply system 200 according to Figure 6 . The power supply system 200 includes a voltage converter 20 and a driving voltage adjustment circuit (not labeled in the figure). The voltage converter 20 is driven by a driving voltage Vdr and includes a switching element group. The switching element group includes two switching elements Ta and Tb. The driving voltage adjustment circuit includes a sensing unit 220, a voltage dividing unit 230, and an adjustment unit 240. The sensing unit 220 is disposed around one of the two switching elements Ta and Tb and is used to sense the temperature of this switching element. Figure 7 In Figure 2 , taking the sensing unit 220 being disposed around the switching element Tb as an example, it is used to sense the temperature of the switching element Tb. In the fourth embodiment, the voltage dividing unit 230 and the adjustment unit 240 can operate in the same manner as the voltage dividing unit 130 and the adjustment unit 140 of the first embodiment, and the voltage converter 20 can be
[0052] Although the present invention has been disclosed as above in embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be defined by the appended claims.
Claims
1. A driving voltage adjustment circuit, characterized in that, Comprising: A sensing unit, disposed around a switching element of a voltage converter, and configured to sense a temperature of the switching element of the voltage converter; A voltage dividing unit, electrically connected to the sensing unit and the voltage converter, and receiving a driving voltage, the voltage dividing unit divides the driving voltage according to the temperature of the switching element to generate a divided voltage; and An adjusting unit, electrically connected to the voltage dividing unit, and receiving an input voltage and the divided voltage, the adjusting unit adjusts the input voltage according to the divided voltage to output the driving voltage, and the driving voltage is transmitted to the voltage converter; Wherein, the temperature is positively correlated with the driving voltage.
2. The drive voltage adjustment circuit according to claim 1, wherein The adjusting unit is a DC-DC converter or a linear voltage regulator.
3. The driving voltage adjustment circuit according to claim 1, wherein The adjusting unit comprises: A power amplifier, electrically connected to the voltage dividing unit, and generating a comparison signal according to the divided voltage; A pulse width modulation controller, electrically connected to the power amplifier, and generating a pulse signal according to the comparison signal; and A switching element group, electrically connected to the pulse width modulation controller, and adjusting the input voltage according to the pulse signal to output the driving voltage.
4. The drive voltage adjustment circuit according to claim 3, wherein The adjusting unit further comprises: A filtering unit, electrically connected between the switching element group and the voltage converter.
5. The driving voltage adjustment circuit according to claim 1, wherein The adjusting unit comprises: A power amplifier, electrically connected to the voltage dividing unit, and generating a comparison signal according to the divided voltage; and Another switching element, electrically connected to the power amplifier, and adjusting the input voltage according to the comparison signal to output the driving voltage.
6. A power supply system, characterized in that, Comprising: A voltage converter, driven by a driving voltage, and comprising: A switching element group, including two switching elements; and A driving voltage adjusting circuit, including; A sensing unit, disposed around one of the two switching elements, and configured to sense a temperature of the one of the two switching elements; A voltage dividing unit, electrically connected to the sensing unit and the voltage converter, and receiving the driving voltage, the voltage dividing unit divides the driving voltage according to the temperature of the one of the two switching elements to generate a divided voltage; and An adjusting unit, electrically connected to the voltage dividing unit, and receiving an input voltage and the divided voltage, the adjusting unit adjusts the input voltage according to the divided voltage to output the driving voltage, and the driving voltage is transmitted to the voltage converter; Wherein, the temperature is positively correlated with the driving voltage.
7. The power supply system according to claim 6, characterized in that, The adjusting unit is a DC-DC converter or a linear voltage regulator.
8. The power supply system according to claim 6, wherein, The adjusting unit comprises: A power amplifier, electrically connected to the voltage dividing unit, and generating a comparison signal according to the divided voltage; A pulse width modulation controller, electrically connected to the power amplifier, and generating a pulse signal according to the comparison signal; and Another switching element group, electrically connected to the pulse width modulation controller, and adjusting the input voltage according to the pulse signal to output the driving voltage.
9. The power supply system according to claim 8, characterized in that, The adjusting unit further comprises: A filtering unit, electrically connected between the another switching element group and the voltage converter.
10. The power supply system according to claim 6, wherein The adjusting unit comprises: A power amplifier, electrically connected to the voltage dividing unit, and generating a comparison signal according to the divided voltage; and Another switching element is electrically connected to the power amplifier and adjusts the input voltage according to the comparison signal to output the driving voltage.