JP2023132292A - Switching power supply device, method for manufacturing switching power supply device, and manufacturing device - Google Patents

Abstract

To provide a switching power supply device, a method for manufacturing the switching power supply device, and a manufacturing device to reduce processing load on a control unit that generates a PWM signal.SOLUTION: A switching power supply device (1A) includes a storage unit (102) for storing adjustment information regarding adjustment of duty ratios of first to fourth PWM signals and a connection unit for receiving input of adjustment information from an external device (2A) to the storage unit, and a PWM signal generation unit (110) generates first to fourth PWM signals based on the adjustment information stored in the storage unit.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a switching power supply device, a method for manufacturing the same, and a manufacturing device.

2. Description of the Related Art Conventionally, measures have been taken to prevent magnetic bias in a transformer in a DC-DC converter having a full bridge circuit. The DC-DC converter described in Patent Document 1 includes a first switch means driven by a first PWM signal and a second switch means driven by a second PWM signal, and the first switch means is driven by a first PWM signal, and the first switch means is driven by a second PWM signal. A first on time during which the switch means is on and a second on time during which the second switch means is on are measured. Then, the duty ratio of the first PWM signal or the second PWM signal is corrected based on the difference between the first on time and the second on time.

Japanese Patent Application Publication No. 2014-124029

However, in the correction method as disclosed in Patent Document 1, the bias in the current flowing through the transformer is dynamically detected during the operation of the DC-DC converter and the duty ratio is corrected, so the processing load of the control unit that generates the PWM signal increases. is large.

One aspect of the present disclosure aims to provide a switching power supply device with a small processing load on a control unit that generates a PWM signal.

In order to solve the above problems, a switching power supply device according to one aspect of the present disclosure is a switching power supply device that converts an input voltage input from a power source into a predetermined voltage and supplies the converted voltage to a load. a transformer that converts an input voltage input from the power source; first and second switching elements that turn on and off a first current flowing in a first direction to the primary side of the transformer; third and fourth switching elements that turn on and off a second current flowing to the side in a second direction opposite to the first direction; and when the first current flows to the primary side of the transformer, the a first rectifying element that guides a current flowing through the secondary side of the transformer to the load; and a first rectifying element that guides the current flowing through the secondary side of the transformer to the load when the second current flows to the primary side of the transformer. a second rectifying element; transmitting a first PWM signal to the first switching element; transmitting a second PWM signal to the second switching element; transmitting a third PWM signal to the third switching element; a PWM signal generating section that controls the on/off operations of each of the first to fourth switching elements by transmitting a fourth PWM signal to the storage device; and a connection unit that receives input of the adjustment information from an external device to the storage unit, and the PWM signal generation unit generates the adjustment information based on the adjustment information stored in the storage unit. 1 to generate a fourth PWM signal.

According to the above configuration, the PWM signal generation section generates the first to fourth PWM signals based on the adjustment information stored in the storage section. Therefore, since the bias in the current flowing through the transformer is not dynamically detected during the operation of the DC-DC converter, the processing load on the control section that generates the PWM signal can be reduced.

Further, in the switching power supply device according to one aspect of the present disclosure, the adjustment information may include at least one of the first and second PWM signals when the current value of the first current is larger than the current value of the second current. is determined such that the duty ratio of the third and fourth PWM signals is smaller than that of the third and fourth PWM signals, and when the current value of the first current is smaller than the current value of the second current, the third and fourth PWM signals The duty ratio of at least one of the signals is determined to be smaller than the duty ratios of the first and second PWM signals.

According to the above configuration, the adjustment information stored in the storage unit is such that when the first current is larger than the second current, the duty ratio of at least one of the first and second PWM signals is equal to the duty ratio of the third and fourth PWM signals. It is designed to be smaller than the ratio. On the other hand, the adjustment information indicates that when the current value of the first current is smaller than the current value of the second current, the duty ratio of at least one of the third and fourth PWM signals is greater than the duty ratio of the first and second PWM signals. It's getting smaller. Therefore, the difference between the current value of the first current and the current value of the second current can be reduced by the PWM signal generation section generating the first to fourth PWM signals based on the adjustment information.

Further, the switching power supply device according to one aspect of the present disclosure further includes a current measurement unit that measures the current values of the first current and the second current, and the current measurement unit measures the current values of the first current and the second current through the connection unit. Each current value of the first current and the second current is output to the external device, and the adjustment information determined based on the current values of the first current and the second current is output from the external device. The input is received and stored in the storage unit.

According to the above configuration, the current measurement unit further includes a current measurement unit that measures the current values of the first current and the second current, and outputs each current value of the first current and the second current measured by the current measurement unit to an external device. . Then, input from an external device is received regarding adjustment information determined based on the current values of the first current and the second current, and the input is stored in the storage unit. Since the switching power supply device includes a current measuring section and can easily measure the current value, it becomes easy to store the adjustment information in the storage section.

Further, in the switching power supply device according to one aspect of the present disclosure, the adjustment information includes a plurality of patterns in which targets for duty ratio adjustment and adjustment amounts are predetermined from among the first to fourth PWM signals. , the variation within the rated tolerance between the on-resistance values of the first to fourth switching elements, and the forward voltage and on-resistance values of the first and second rectifying elements is the same as the current value of the first current and the on-resistance value of the first current. The adjustment information is unified into the difference between the current value of the second current and one pattern of the adjustment information corresponding to the difference between the current value of the first current and the current value of the second current is stored in the storage unit.

According to the above configuration, the variation within the rated tolerance between the on-resistance values of the first to fourth switching elements and the forward voltages of the first and second rectifying elements is determined by the current value of the first current and the second current. The adjustment information of one pattern corresponding to the difference between the current value of the first current and the current value of the second current is stored in the storage unit. Therefore, the switching power supply device can be easily adjusted without measuring the on-resistance values of the first to fourth switching elements and the forward voltage and on-resistance values of the first and second rectifying elements.

A method for manufacturing a switching power supply device according to an aspect of the present disclosure includes an input step of inputting the results of measuring the current values of the first current and the second current into an external device; a determining step of determining the adjustment information based on the difference between the current value of the second current and the current value of the second current; and transmitting the adjustment information determined in the determining step to the storage section via the connection section. and a writing step of storing the information in the memory.

According to the above configuration, adjustment information is determined based on the difference between the current value of the first current and the current value of the second current, and the adjustment information is stored in the storage section of the switching power supply device. Since the adjustment information is determined at the manufacturing stage and stored in the storage unit, there is no need to dynamically detect deviations in the current flowing through the transformer while the DC-DC converter is operating. The processing load can be reduced.

A method for manufacturing a switching power supply device according to an aspect of the present disclosure includes an input for inputting measurement results of current values of the first current and the second current by the current measurement unit to the external device via the connection unit. a determining step in which the external device determines the adjustment information based on the difference between the current values of the first current and the second current; and a writing step of storing data in the storage section via the connection section.

According to the above configuration, the current value of the first current and the current value of the second current are measured using the current measuring section, and the adjustment information is determined based on the measurement results. Therefore, the first current and the second current can be easily measured and adjustment information can be determined.

A manufacturing apparatus according to an aspect of the present disclosure includes an input receiving unit that receives input of current values of the first current and the second current, and a current value of the first current input from the switching power supply device and the second current. The power supply device includes a determination unit that determines the adjustment information based on a difference between two current values, and an output unit that outputs the adjustment information determined by the determination unit to the switching power supply device.

According to the above configuration, the manufacturing device determines the adjustment information based on the difference between the current value of the first current and the current value of the second current, and outputs the adjustment information to the switching power supply device. Since the adjustment information is determined at the manufacturing stage and stored in the storage unit, there is no need to dynamically detect deviations in the current flowing through the transformer while the DC-DC converter is operating. The processing load can be reduced.

Further, the manufacturing apparatus according to one aspect of the present disclosure includes an input that receives an input of measurement results of the current values of the first current and the second current by the current measurement unit via the connection unit of the switching power supply device. a receiving unit, a determining unit that determines the adjustment information based on a difference between the current value of the first current and the current value of the second current input from the switching power supply device; and an output unit that outputs the adjusted adjustment information to the switching power supply device.

According to the above configuration, the current value of the first current and the current value of the second current are measured using the current measuring section, and the adjustment information is determined based on the measurement results. Therefore, the first current and the second current can be easily measured and adjustment information can be determined.

According to one aspect of the present disclosure, the processing load on a control unit that generates a PWM signal can be reduced.

FIG. 1 is a circuit diagram of a switching power supply device according to Embodiment 1 of the present disclosure. FIG. 3 is a diagram showing the direction of current flowing through a DC-DC converter included in the switching power supply device according to Embodiment 1 of the present disclosure. FIG. 2 is a diagram for explaining a PWM signal input to a switching element constituting a DC-DC converter and a duty ratio. FIG. 3 is a diagram for explaining the relationship between a pattern of biased magnetism in a DC-DC converter and adjustment of a duty ratio. FIG. 3 is a diagram illustrating an example of a method for adjusting the duty ratio of a PWM signal. FIG. 3 is a diagram illustrating an example of a method for adjusting the duty ratio of a PWM signal. 1 is a flowchart illustrating a method for manufacturing a switching power supply device according to Embodiment 1 of the present disclosure. FIG. 2 is a circuit diagram of a switching power supply device according to Embodiment 2 of the present disclosure. 7 is a flowchart illustrating a method for manufacturing a switching power supply device according to Embodiment 2 of the present disclosure. FIG. 3 is a diagram for explaining the relationship between a pattern of biased magnetism in a DC-DC converter and adjustment of a duty ratio.

[Embodiment 1]
FIG. 1 is a circuit diagram of a switching power supply device according to Embodiment 1 of the present disclosure. The switching power supply device 1A shown in FIG. 1 includes a DC-DC converter 100A, a control section 101A, a storage section 102, and a connection section 103. The DC-DC converter 100A includes four switching elements Q1 to Q4 forming a full bridge circuit, a transformer TR, and a first rectifying element D1 and a second rectifying element D2. In the DC-DC converter 100A, an input voltage input from a power source (not shown) is converted into a predetermined voltage by a transformer TR, and the converted voltage is supplied to a load (not shown).

The switching element Q1 is an example of a first switching element, and is composed of an FET. The switching element Q4 is an example of a second switching element, and is composed of an FET. The switching element Q2 is an example of a third switching element, and is composed of an FET. The switching element Q3 is an example of a fourth switching element, and is composed of an FET. Switching elements Q1-Q4 may be configured with IGBTs or bipolar transistors.

The first rectifying element D1 and the second rectifying element D2 are composed of diodes. The first rectifying element D1 and the second rectifying element D2 guide the current flowing through the secondary side of the transformer TR to the load side of the DC-DC converter 100A. The first rectifying element D1 and the second rectifying element D2 may be configured with switching elements such as FETs, and may perform synchronous rectification.

The control unit 101A is composed of, for example, a microcomputer, and functions as the PWM signal generation unit 110 by executing a program stored in the storage unit 102. PWM signal generation section 110 generates PWM signals to be input to the gates of four switching elements Q1-Q4 of DC-DC converter 100A. Switching elements Q1-Q4 perform on/off operations based on PWM signals generated by PWM signal generation section 110.

The connecting portion 103 of the switching power supply device 1A is connected to the manufacturing device 2A during the manufacturing stage of the switching power supply device 1A. The manufacturing stage includes not only the stage of assembling the switching power supply device 1A, but also the stage of testing the operation of the switching power supply device 1A or its parts. The connection unit 103 is, for example, a connector or pigtail provided in the housing of the switching power supply device 1A, or a communication module for performing wireless communication with the manufacturing device 2A. The manufacturing device 2A is an external device that is connected to the switching power supply device 1A from the outside through the connection part 103, and is used for manufacturing the switching power supply device 1A. The manufacturing device 2A may be a dedicated device used only for manufacturing the switching power supply device 1A, or may be a computer in which a manufacturing application is installed.

The switching operation by switching elements Q1-Q4 will be explained using FIGS. 2 and 3. FIG. 2 shows the direction of current flowing through the transformer TR due to the switching operation. FIG. 3 is a timing chart showing an example of PWM signals input to the gates of switching elements Q1-Q4.

The top row of FIG. 3 shows an example of the first PWM signal input to the gate of the switching element Q1. The second stage shows an example of the second PWM signal input to the gate of the switching element Q2. The third stage shows an example of the third PWM signal input to the gate of the switching element Q3. The fourth stage shows an example of the fourth PWM signal input to the gate of the switching element Q4. The fifth row indicates whether or not current is flowing through the transformer TR.

The first PWM signal and the second PWM signal are in a complementary relationship. That is, when switching element Q1 is on, switching element Q2 is turned off, and when switching element Q2 is on, switching element Q1 is turned off. Further, the third PWM signal and the fourth PWM signal are in a complementary relationship. That is, when switching element Q3 is on, switching element Q4 is turned off, and when switching element Q3 is on, switching element Q4 is turned off. In FIG. 3, the fourth PWM signal is delayed in phase by 1/4 period from the first PWM signal. The third PWM signal is delayed in phase by 1/4 period from the second PWM signal.

When the first PWM signal and the fourth PWM signal are turned on and the switching elements Q1 and Q4 are turned on, a current C11 flows to the primary side of the transformer TR, as shown in FIG. 2(A). At this time, on the secondary side of the transformer TR, a current C12 flows through the first rectifying element D1. Hereinafter, the direction in which the currents C11 and C12 flow will be referred to as a first direction, and the current flowing in the first direction will be referred to as a first current.

When the second PWM signal and the third PWM signal are turned on and the switching elements Q2 and Q3 are turned on, a current C21 in the second direction flows to the primary side of the transformer TR, as shown in FIG. 2(B). At this time, on the secondary side of the transformer TR, a current C22 flows through the second rectifying element D2. Hereinafter, the direction in which the currents C21 and C22 flow will be referred to as a second direction, and the current that flows in the second direction will be referred to as a second current.

The switching power supply device 1A is ideally designed so that the current value of the first current C11 and the current value of the second current C21 are equal. However, in reality, due to variations in the characteristic values that indicate the ease with which current flows in the components of the DC-DC converter 100A, a difference occurs between the current value of the first current C11 and the current value of the second current C21, and the transformer A magnetic bias phenomenon may occur in the TR. The characteristic values indicating ease of current flow include, for example, the on-resistance value of switching elements Q1-Q4, the forward voltage and on-resistance value of the first rectifying element D1, and the forward voltage and on-resistance value of the second rectifying element D2. It is a value. These characteristic values may vary within the rated tolerance defined as the product specifications for each component.

However, it is difficult to measure characteristic values indicating the ease with which current flows for all the components of the DC-DC converter 100A. Therefore, in the switching power supply device 1A, the variation within the rated tolerance between the on-resistance values of the switching elements Q1-Q4 and the forward voltage and on-resistance values of the first rectifying element D1 and the second rectifying element D2 is The information is unified into the difference between the current value of the current C11 and the current value of the second current C21. That is, variations within the rated tolerance among the on-resistance values of switching elements Q1-Q4, the forward voltage and on-resistance value of the first rectifying element D1, and the forward voltage and on-resistance value of the second rectifying element D2, etc. , high-dimensional information including a plurality of parameters can be processed using one-dimensional information of the difference between the current value of the first current C11 and the current value of the second current C21. At the manufacturing stage of the switching power supply device 1A, the current values of the first current C11 and the second current C21 are measured, and the differences in the current values are classified into a plurality of patterns. Then, adjustment is performed using a method determined for each pattern so that the difference between the current value of the first current C11 and the current value of the second current C21 becomes small.

Adjustment to reduce the difference in current values is performed by reducing the duty ratio of any one of the first to fourth PWM signals. Specifically, when decreasing the first current C11, the duty ratio of the first PWM signal or the fourth PWM signal is decreased. When reducing the second current C21, the duty ratio of the second PWM signal or the third PWM signal is reduced.

Adjustment information regarding adjustment performed for each pattern is stored in the storage unit 102 during the manufacturing stage of the switching power supply device 1A. The adjustment information includes information regarding the adjustment target indicating whether to adjust the duty ratio of the PWM signal on the first current C11 side or the duty ratio of the PWM signal on the second current C21 side, and information indicating the amount of adjustment. is included. The PWM signal generation section 110 generates the first to fourth PWM signals by referring to the adjustment information stored in the storage section 102.

FIG. 4 shows an example of adjustment information. In the adjustment table 300 shown in FIG. 4, the difference between the current value of the first current C11 and the current value of the second current C21 is classified into seven patterns, and adjustment information for each pattern is illustrated.

The first pattern is a pattern in which the difference between the current value of the first current C11 and the current value of the second current C21 is close to zero, and no adjustment is performed. For example, if the absolute value of the difference between the current value of the first current C11 and the current value of the second current C21 is less than 2 A, it is classified as the first pattern.

The second to fourth patterns are patterns in which the first current C11 is larger than the second current C21, and are classified based on the magnitude of the difference in current values. For example, if the difference in current value is 2 A or more and less than 4 A, it is classified as the second pattern. If the difference in current value is 4 A or more and less than 6 A, it is classified as the third pattern. If the difference in current value is 6 A or more, it is classified into the fourth pattern. In the second to fourth patterns, the duty ratio of the first PWM signal or the fourth PWM signal is reduced in order to reduce the first currents C11 and C12.

FIG. 5 shows an example of adjusting the duty ratio of the first PWM signal or the fourth PWM signal, which is executed in the second pattern to the fourth pattern. In the adjustment shown in FIG. 5A, the rising timing of the first PWM signal is delayed by a predetermined time A1, and the duty ratio of the first PWM signal is reduced. In the adjustment shown in FIG. 5B, the falling timing of the fourth PWM signal is advanced by a predetermined time A2, and the duty ratio of the fourth PWM signal is decreased. The predetermined times A1 and A2 are determined based on adjustment information stored in the storage unit 102.

The PWM signal generation section 110 refers to the adjustment information stored in the storage section 102 and performs the adjustment as shown in FIG. 5(A) or (B) based on the adjustment information. When either of the adjustments shown in FIGS. 5A and 5B is performed, the period during which switching elements Q1 and Q4 are simultaneously turned on becomes shorter, and the first currents C11 and C12 become smaller.

Note that the PWM signal generation unit 110 may adjust the duty ratio of the first PWM signal shown in FIG. 5(A) and adjust the duty ratio of the fourth PWM signal shown in FIG. 5(B) at the same time. good.

On the other hand, the fifth to seventh patterns are patterns in which the second current C21 is larger than the first current C11, and are classified based on the magnitude of the difference in current value. For example, if the difference in current value is 2 A or more and less than 4 A, it is classified as the fifth pattern. If the difference in current value is 4 A or more and less than 6 A, it is classified as the sixth pattern. If the difference in current value is 6 A or more, it is classified into the seventh pattern. In the fifth to seventh patterns, the duty ratio of the second PWM signal or the third PWM signal is reduced in order to reduce the second currents C21 and C22.

FIG. 6 shows an example of adjusting the duty ratio of the second PWM signal or the third PWM signal, which is executed in the fifth pattern to the seventh pattern. In the adjustment shown in FIG. 6A, the rising timing of the second PWM signal is delayed by a predetermined time A3, and the duty ratio of the second PWM signal is reduced. In the adjustment shown in FIG. 6(B), the timing of the fall of the third PWM signal is advanced by a predetermined time A4, and the duty ratio of the third PWM signal is decreased. The predetermined times A3 and A4 are determined based on adjustment information stored in the storage unit 102.

The PWM signal generation section 110 refers to the adjustment information stored in the storage section 102 and performs the adjustment as shown in FIG. 6(A) or (B) based on the adjustment information. When either of the adjustments shown in FIGS. 6A and 6B is performed, the period during which switching elements Q2 and Q3 are simultaneously turned on becomes shorter, and the second currents C21 and C22 become smaller.

Note that the PWM signal generation unit 110 may adjust the duty ratio of the second PWM signal shown in FIG. 6(A) and adjust the duty ratio of the third PWM signal shown in FIG. 6(B) at the same time. good.

A method of manufacturing the switching power supply device 1A will be described with reference to FIGS. 1 and 7. FIG. 7 is a flowchart illustrating an example of a method for manufacturing the switching power supply device 1A. In the method for manufacturing the switching power supply device 1A, a manufacturing device 2A is used. As shown in FIG. 1, the manufacturing apparatus 2A includes an input receiving section 201, a determining section 202, and an output section 203.

In the method for manufacturing the switching power supply device 1A shown in FIG. 7, first, the current values of the first current C11 and the second current C21 are measured, and the measured values are input to the manufacturing device 2A (S100). The current value is measured by a worker at the manufacturing site of the switching power supply device 1 using a well-known method such as a method using a shunt resistor. The manufacturing apparatus 2A functions as an input reception unit 201 and receives input of measurement results of current values. The input reception unit 201 receives, for example, information input by a worker using a keyboard or the like.

Next, the manufacturing apparatus 2A functions as the determination unit 202 and determines adjustment information based on the current values of the first current C11 and the second current C21 input in step S100 (S101). For example, the manufacturing apparatus 2A calculates the difference between the current value of the first current C11 and the current value of the second current C21, and determines to which of the seven patterns shown in FIG. 4 the difference applies. The manufacturing apparatus 2A then determines adjustment information determined for each pattern.

Next, the manufacturing apparatus 2A functions as an output unit 203, outputs the adjustment information determined in step S101 to the switching power supply 1A through the connection unit 103, and stores the adjustment information in the storage unit 102 of the switching power supply 1. to save.

(Operations and effects of Embodiment 1)
The switching power supply device 1A described above receives input of adjustment information regarding adjustment of the duty ratio of the first to fourth PWM signals from the external manufacturing device 2A via the connection section 103, and stores it in the storage section 102. Then, the PWM signal generation section 110 generates the first to fourth PWM signals based on the adjustment information stored in the storage section 102. Therefore, since there is no need to dynamically detect the deviation of the current flowing through the transformer during operation of the DC-DC converter, the processing load of the PWM signal generation section 110 applied to the control section 101A can be reduced.

When the current value of the first current C11 is larger than the current value of the second current C21, the adjustment information includes the adjustment information of at least one of the first PWM signal and the fourth PWM signal, as shown in FIG. 5(A) or (B). The duty ratio is smaller than the duty ratios of the second PWM signal and the third PWM signal. Further, when the current value of the first current C11 is smaller than the current value of the second current C21, the adjustment information includes at least one of the second PWM signal and the third PWM signal, as shown in FIG. 6(A) or (B). The duty ratio of one of the signals is smaller than the duty ratios of the first PWM signal and the fourth PWM signal. Therefore, by the PWM signal generating section 110 generating the first to fourth PWM signals based on the adjustment information, it is possible to reduce the difference between the current values of the first current C11 and the second current C21.

As illustrated in FIG. 4, the adjustment information includes a plurality of patterns in which targets of duty ratio adjustment from among the first to fourth PWM signals and adjustment amounts are predetermined. Then, the variation within the rated tolerance between the on-resistance values of the switching elements Q1-Q4 and the forward voltage and on-resistance values of the first rectifying element D1 and the second rectifying element D2 is determined as the current value of the first current C11. The difference from the current value of the second current C21 is unified, and one pattern of adjustment information corresponding to the difference in current value is stored in the storage unit 102. Therefore, the switching power supply device 1A can be easily adjusted without measuring the on-resistance values of the switching elements Q1 to Q4 and the forward voltages of the first rectifying element D1 and the second rectifying element D2 at the manufacturing stage of the switching power supply device 1A. be able to.

As shown in FIG. 7, the manufacturing method of the switching power supply device 1A includes a step in which the manufacturing device 2A determines adjustment information based on the difference between the current value of the first current and the current value of the second current (S101). ), and a step (S102) of storing the adjustment information in the storage section of the switching power supply device 1A. Since the adjustment information is determined at the manufacturing stage and stored in the storage unit, there is no need to dynamically detect deviations in the current flowing through the transformer during operation of the DC-DC converter, and PWM signal generation to be applied to the control unit 101A is possible. The processing load on the unit 110 can be reduced.
[Embodiment 2]
Other embodiments of the present disclosure will be described below. For convenience of explanation, members having the same functions as the members described in the above embodiment are given the same reference numerals, and the description thereof will not be repeated.

FIG. 8 is a circuit diagram of a switching power supply device according to Embodiment 2 of the present disclosure. A switching power supply device 1B shown in FIG. 8 includes a DC-DC converter 100B, a control section 101B, a storage section 102, and a connection section 103. DC-DC converter 100B differs from DC-DC converter 100A in that it includes a current detection section 104 therein. Current detection section 104 detects the current flowing through transformer TR, and outputs information regarding the detected current value to control section 101B.

The control section 101B is made up of a microcomputer similarly to the control section 101A. The control unit 101B differs from the control unit 101A in that it also functions as a current measurement unit 111 by executing a program stored in the storage unit 102. The current measurement unit 111 measures the current flowing to the primary side of the transformer TR, that is, the first current C11 and the second current C21, based on the detection result of the current detection unit 104.

With reference to FIG. 9, a method for manufacturing the switching power supply device 1B will be described. FIG. 9 is a flowchart illustrating an example of a method for manufacturing the switching power supply device 1B. In the method for manufacturing the switching power supply device 1B, a manufacturing device 2B is used. The manufacturing device 2B may be a dedicated device used only for manufacturing the switching power supply device 1B, or may be a computer in which a manufacturing application is installed.

The method for manufacturing the switching power supply device 1B shown in FIG. 9 differs from the method for manufacturing the switching power supply device 1A in the method of inputting the current values of the first current C11 and the second current C21 to the manufacturing device 2B. In the method for manufacturing the switching power supply device 1B, the control unit 101B functions as the current measurement unit 111, acquires information regarding the current flowing to the primary side of the transformer TR from the current detection unit 104, and adjusts the first current C11 and the current C11 based on the information. The current value of the second current C21 is measured (S200). Then, the control unit 101B inputs the current values of the first current C11 and the second current C21 measured in step S200 to the manufacturing apparatus 2B via the connection unit 103 (S201). The subsequent steps are similar to the method for manufacturing the switching power supply device 1A described using FIG.

(Operations and effects of Embodiment 2)
The switching power supply device 1B described above further includes a current measuring section 111 that measures the current values of the first current C11 and the second current C21. Then, during the manufacturing stage of the switching power supply device, the current values of the first current C11 and the second current C21 measured by the current measuring section are output to the manufacturing apparatus 2B. Then, the adjustment information determined by the manufacturing apparatus 2B based on the current values of the first current C11 and the second current C21 is stored in the storage unit 102. Since the switching power supply device 1B includes the current measuring section 111 and can easily measure the current value, it becomes easy to store the adjustment information in the storage section.

As shown in FIG. 9, the method for manufacturing the switching power supply device 1B includes a step (S200) of measuring the current values of the first current C11 and the second current C21 using the current measuring section 111, and manufacturing the measured values. and a step of inputting to the device 2B (S201). Since it was decided to measure the first current C11 and the second current C21 using the current measuring section 111, manufacturing of the switching power supply device 1B becomes easy.

(Modified example)
In the first and second embodiments described above, the difference between the current value of the first current C11 and the current value of the second current C21 is classified into one of the seven patterns shown in FIG. The duty ratio of any one of the first to fourth PWM signals was adjusted based on the adjustment information obtained. However, the method of classifying the difference between the current value of the first current C11 and the current value of the second current C21 is not limited to the method of classifying into any of the seven patterns illustrated in FIG. 4 . For example, if the difference between the current value of the first current C11 and the current value of the second current C21 is close to zero, if the current value of the first current C11 is larger, then the current value of the second current C21 is larger. The situation may be classified into three patterns. Alternatively, the patterns may be classified into seven or more patterns.

Further, the adjustment information may be determined based on information other than the difference between the current value of the first current C11 and the current value of the second current C21. For example, as in the adjustment table 301 illustrated in FIG. 10, the pattern of biased magnetism in the DC-DC converter 100A may be classified to determine the adjustment information.

In the adjustment table 301 shown in FIG. 10, the DC-DC converter is adjusted using six parameters: the on-resistance value of the switching elements Q1-Q4, the forward voltage of the first rectifying element D1, and the forward voltage of the second rectifying element D2. The patterns of biased magnetism at 100A are classified. If the switching element Q1 of the 100A DC-DC converter has characteristics that allow current to easily flow, that is, if the on-resistance value of the switching element Q1 is close to the minimum value of the rated tolerance, a plus sign is added to the Q1 column. It is classified into one of the following patterns. Conversely, if the switching element Q1 has characteristics that make it difficult for current to flow, that is, if the on-resistance value of the switching element Q1 is close to the maximum value of the rated tolerance, then either of the patterns with a minus sign in the Q1 column It is classified as crab. Similarly, if each of the switching elements Q2-Q4 has a characteristic that allows current to flow easily, it is classified into one of the patterns in which a plus sign is attached to each column of Q2-Q4. If each of the switching elements Q2-Q4 has a characteristic that makes it difficult for current to flow, it is classified into one of the patterns in which a minus sign is attached to each column of Q2-Q4.

If the first rectifying element D1 has a characteristic that allows current to easily flow, that is, if the forward voltage of the first rectifying element D1 is close to the minimum value within the product specifications, a pattern with a plus sign in the D1 column is used. It is classified as one of the following. Conversely, if the first rectifying element D1 has a characteristic that makes it difficult for current to flow, that is, if the forward voltage of the first rectifying element D1 is close to the maximum value within the product specifications, a minus sign is added to the D1 column. It is classified into one of the following patterns. When the second rectifying element D2 has a characteristic that allows current to flow easily, it is classified into one of the patterns with a plus sign attached to the D2 column. Conversely, when the second rectifying element D2 has a characteristic that makes it difficult for current to flow, it is classified into one of the patterns with a minus sign attached to the D2 column.

Using six parameters: on-resistance values of switching elements Q1-Q4, forward voltage of first rectifying element D1, and forward voltage of second rectifying element D2, adjust the row close to the state of DC-DC converter 100A in the table. 301 to determine adjustment information. For example, if the switching elements Q1 to Q4, the first rectifying element D1, and the second rectifying element D2 of the DC-DC converter 100A all have characteristics that allow current to flow easily, pattern 1 adjustment information is determined. If all of the switching elements Q1-Q4, the first rectifying element D1, and the second rectifying element D2 of the DC-DC converter 100A have characteristics that allow current to flow easily, both the first current C11 and the second current C21 are set at the design stage. Therefore, it is highly likely that there is no difference between the current value of the first current C11 and the current value of the second current C21. Therefore, in the adjustment amount column and the adjustment target column of pattern 1 in FIG. 10, adjustment information indicating that there is no need to adjust the duty ratios of any of the first to fourth PWM signals is shown. Note that the adjustment table 301 in FIG. 10 shows that at least one of the on-resistance values of the switching elements Q1 to Q4, the forward voltage of the first rectifying element D1, and the forward voltage of the second rectifying element D2 is at the rated value. Pattern is omitted. If at least one of the on-resistance values of the switching elements Q1 to Q4, the forward voltage of the first rectifying element D1, and the forward voltage of the second rectifying element D2 is the rated value, the first to fourth PWM This is because it is determined that there is no need to adjust the duty ratio of any signal.

The present disclosure is not limited to the embodiments described above, and various changes can be made within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. are also included within the technical scope of the present disclosure.

1A, 1B Switching power supply device 2A, 2B Manufacturing equipment 100A, 100B DC-DC converter 102 Storage section 103 Connection section 104 Current detection section 110 PWM signal generation section 111 Current measurement section 201 Input reception section 202 Determination section 203 Output section 300, 301 Adjustment table C11, C12 1st current C21, C22 2nd current

Claims (8)

A switching power supply device that converts an input voltage input from a power supply into a predetermined voltage and supplies the converted voltage to a load,
a transformer that converts an input voltage input from the power source;
first and second switching elements that turn on and off a first current flowing in a first direction to the primary side of the transformer;
third and fourth switching elements that turn on and off a second current flowing in a second direction opposite to the first direction to the primary side of the transformer;
a first rectifying element that guides the current flowing to the secondary side of the transformer to the load when the first current flows to the primary side of the transformer;
a second rectifying element that guides the current flowing to the secondary side of the transformer to the load when the second current flows to the primary side of the transformer;
Sending a first PWM signal to the first switching element, sending a second PWM signal to the second switching element, sending a third PWM signal to the third switching element, and sending a fourth PWM signal to the fourth switching element. a PWM signal generation unit that controls the on/off operation of each of the first to fourth switching elements;
a storage unit that stores adjustment information regarding adjustment of duty ratios of the first to fourth PWM signals;
a connection part that receives input of the adjustment information from an external device to the storage part,
The switching power supply device, wherein the PWM signal generation section generates the first to fourth PWM signals based on the adjustment information stored in the storage section. The adjustment information is
When the current value of the first current is larger than the current value of the second current, the duty ratio of at least one of the first and second PWM signals is smaller than the duty ratio of the third and fourth PWM signals. It was decided that
When the current value of the first current is smaller than the current value of the second current, the duty ratio of at least one of the third and fourth PWM signals is set to be smaller than the duty ratio of the first and second PWM signals. The switching power supply device according to claim 1, characterized in that the switching power supply device is determined as follows. further comprising a current measurement unit that measures current values of the first current and the second current,
Via the connection,
outputting each current value of the first current and the second current measured by the current measurement unit to the external device;
3. The adjustment information determined based on the current values of the first current and the second current receives an input from the external device and stores the adjustment information in the storage unit. switching power supply. The adjustment information includes a plurality of patterns in which targets for duty ratio adjustment from among the first to fourth PWM signals and adjustment amounts are predetermined;
The variation within the rated tolerance between the on-resistance values of the first to fourth switching elements and the forward voltage and on-resistance values of the first and second rectifying elements is determined by the current value of the first current and the on-resistance value of the first to fourth switching elements. It is unified into the difference between the current value of two currents,
Any one of claims 1 to 3, wherein one pattern of the adjustment information corresponding to a difference between the current value of the first current and the current value of the second current is stored in the storage unit. Switching power supplies as described in Section. A method for manufacturing a switching power supply device, comprising: manufacturing the switching power supply device according to any one of claims 1 to 4.
an input step of inputting the results of measuring the current values of the first current and the second current into the external device;
a determining step in which the external device determines the adjustment information based on a difference between the current value of the first current and the current value of the second current;
a writing step of storing the adjustment information determined in the determining step in the storage section via the connection section;
A method of manufacturing a switching power supply device, comprising: A method for manufacturing a switching power supply device, comprising: manufacturing the switching power supply device according to claim 3 or 4.
an input step of inputting the measurement results of the current values of the first current and the second current by the current measurement unit to the external device via the connection unit;
a determining step in which the external device determines the adjustment information based on a difference in current value between the first current and the second current;
a writing step of storing the adjustment information determined in the determining step in the storage section via the connection section;
A method of manufacturing a switching power supply device, comprising: A manufacturing apparatus used for manufacturing the switching power supply device according to any one of claims 1 to 4,
an input reception unit that receives input of current values of the first current and the second current;
a determining unit that determines the adjustment information based on a difference between the current value of the first current and the current value of the second current input from the switching power supply device;
A manufacturing apparatus comprising: an output section that outputs the adjustment information determined by the determination section to the switching power supply device. A manufacturing apparatus used for manufacturing the switching power supply device according to claim 3 or 4, comprising:
an input reception unit that receives input of measurement results of the first current and the second current by the current measurement unit via the connection unit of the switching power supply;
a determining unit that determines the adjustment information based on a difference between the current value of the first current and the current value of the second current input from the switching power supply device;
A manufacturing apparatus comprising: an output section that outputs the adjustment information determined by the determination section to the switching power supply device.

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