Embodiments of this application relate to power circuit technologies, and in particular, to an online voltage adjustment circuit for a board power supply.
With rapid development of computer technologies and network technologies, a signal transmission rate becomes increasingly higher, and requirements on output accuracy and reliability of a board power supply also become increasingly higher. In addition, increasingly more electronic components are integrated on the board power supply, and therefore a processing technique is complex. In a board power supply development or production phase, board power supplies that undergo a strict test by a manufacturer still have a specific failure rate. Even though some board power supplies pass an automatic test equipment (ATE) check, a specific percentage of the board power supplies become faulty soon.
In a whole-machine test phase of an electronic device, an online voltage adjustment circuit for a board power supply is used to adjust an output voltage of the board power supply to implement secondary filtering of the board power supply, thereby ensuring relatively strong stability of the board power supply when a range of the output voltage of the board power supply is relatively large, to be specific, ensuring that a design of the board power supply has a specific margin. In an adjustment process, a bias resistor is welded on a feedback (FB) pin of the board power supply. A resistance value of the bias resistor is adjusted such that the FB pin obtains different FB values, and further the board power supply outputs different voltages.
In the foregoing board power supply adjustment process, the bias resistor needs to be manually welded. This is time- and labor-consuming, poor welding easily occurs, and an operation process is complex.
Embodiments of this application provide an online voltage adjustment circuit for a board power supply. An output voltage of the board power supply is adjusted online to reduce complexity of adjustment of the board power supply.
According to a first aspect, an embodiment of this application provides an online voltage adjustment circuit for a board power supply, including a detection chip, a control chip, a first voltage division element, a second voltage division element, a first switch, a second switch, a first bias resistor, and a second bias resistor. A first voltage division circuit is connected in parallel to the first bias resistor, a second voltage division circuit is connected in parallel to the second bias resistor, the detection chip obtains an initial output voltage of the board power supply, and finally, based on the initial output voltage and a preset voltage, the control chip controls on/off of the first switch on the first voltage division circuit, and on/off of the second switch on the second voltage division circuit such that an FB value of an FB pin of the board power supply changes, and then an output voltage of the board power supply changes, thereby adjusting the output voltage of the board power supply.
In the foregoing circuit, during online voltage adjustment, instead of manually welding the bias resistors, the control chip automatically controls on/off of the first switch and the second switch such that the output voltage of the board power supply changes, thereby reducing complexity of adjustment of the output voltage of the board power supply.
With reference to the first aspect, in a possible implementation of the first aspect, the first voltage division element includes a first voltage division resistor, and the second voltage division element includes a second voltage division resistor. When the control chip controls the first switch to be off and the second switch to be off, the initial output voltage is used as a target voltage. Alternatively, when the control chip controls the first switch to be on and the second switch to be off, the initial output voltage is increased to a first voltage, and the first voltage is used as a target voltage. Alternatively, when the control chip controls the first switch to be off and the second switch to be on, the initial output voltage is reduced to a second voltage, and the second voltage is used as a target voltage.
In the foregoing circuit, in the online voltage adjustment process for the board power supply, the detection chip samples the output voltage of the output pin to obtain the initial output voltage, and sends the initial output voltage to the control chip. The control chip controls on/off of the first voltage division resistor and the second voltage division resistor based on the preset voltage and the initial output voltage to adjust the initial output voltage to the target voltage, thereby implementing online voltage adjustment of a fixed bias of the output voltage.
With reference to the first aspect and the foregoing possible implementation of the first aspect, in another possible implementation of the first aspect, the first voltage division element includes a first digital potentiometer, the second voltage division element includes a second digital potentiometer, and the control chip is further connected to the first digital potentiometer and the second digital potentiometer. When the control chip controls the first switch to be off and the second switch to be off, the initial voltage is used as the target voltage. Alternatively, when the control chip controls the first switch to be on and the second switch to be off, the initial voltage is increased to the first voltage, and the first voltage is used as the target voltage. Alternatively, when the control chip controls the first switch to be off and the second switch to be on, the output voltage is reduced to the second voltage, and the second voltage is used as the target voltage. Alternatively, when the control chip controls the first switch to be on and the second switch to be off, and adjusts the first digital potentiometer, the target voltage is between the initial voltage and the first voltage. Alternatively, when the control chip controls the first switch to be off and the second switch to be on, and adjusts the second digital potentiometer, the target voltage is between the second voltage and the initial voltage. Alternatively, when the control chip controls the first switch to be on and the second switch to be on, and adjusts the first digital potentiometer and the second digital potentiometer, the target voltage is between the second voltage and the first voltage.
In the foregoing circuit, in the online voltage adjustment process for the board power supply, the detection chip samples the output voltage of the output pin to obtain the initial output voltage, and sends the initial output voltage to the control chip. The control chip controls the first digital potentiometer and the second digital potentiometer based on the preset voltage and the initial output voltage to change an FB value, and adjust the initial output voltage to the target voltage, thereby implementing online voltage adjustment of a dynamic bias of the output voltage.
With reference to the first aspect and the possible implementations of the first aspect, in another possible implementation of the first aspect, the first switch is a switching transistor or a metal-oxide semiconductor field-effect transistor, and the second switch is a switching transistor or a metal-oxide semiconductor field-effect transistor.
With reference to the first aspect and the possible implementations of the first aspect, in another possible implementation of the first aspect, the control chip is further configured to obtain the preset voltage.
In the online voltage adjustment circuit for the board power supply that is provided in the embodiments of the present disclosure, the first voltage division circuit is connected in parallel to the first bias resistor, the second voltage division circuit is connected in parallel to the second bias resistor, the detection chip obtains the initial output voltage of the board power supply, and finally, based on the initial output voltage and the preset voltage, the control chip controls on/off of the first switch on the first voltage division circuit, and on/off of the second switch on the second voltage division circuit such that the FB value of the FB pin of the board power supply changes, and then the output voltage of the board power supply changes, thereby adjusting the output voltage of the board power supply. In the adjustment process, instead of manually welding the bias resistors, the control chip automatically controls on/off of the first switch and the second switch such that the output voltage of the board power supply changes, thereby reducing the complexity of adjustment of the output voltage of the board power supply.
Generally, a specific margin needs to be designed for a board power supply of an electronic device to ensure strong stability when a range of an output voltage of the board power supply is relatively large. In an adjustment process, a bias resistor is welded on an FB pin of the board power supply. A resistance value of the bias resistor is adjusted such that the FB pin obtains different FB values, and further the board power supply outputs different voltages. Further, referring to
Referring to
In the foregoing online voltage adjustment circuit for the board power supply, the bias resistors R1 and R2 need to be manually welded. This is time- and labor-consuming, poor welding easily occurs, and an operation process is complex.
In view of the above, embodiments of this application provide an online voltage adjustment circuit for a board power supply. An output voltage of the board power supply is adjusted online to reduce complexity of adjustment of the board power supply. Further, referring to
Referring to
In the foregoing circuit, the detection chip 1 is a voltage detection chip that can sample an output voltage of the board power supply. For example, the detection chip 1 is a multi-channel voltage detection chip. The control chip 2 is, for example, advanced reduced instruction set computing (RISC) machines (ARM), a micro control unit (MCU), or a complex programmable logical device (CPLD). A connection between the detection chip 1 and the control chip 2 is established using an inter-integrated circuit (I2C) or a low pin count (LPC) interface. In an output voltage adjustment process, the detection chip 1 samples an output (Vout) of the output pin of the board power supply to obtain the initial output voltage, and then sends the obtained initial output voltage to the control chip 2. The control chip 2 controls, based on a preset voltage and the initial output voltage, on/off of the first voltage division circuit that is in a parallel connection to the first bias resistor 7, and/or controls, based on a preset voltage and the initial output voltage, on/off of the second voltage division circuit that is in a parallel connection to the second bias resistor 8 in order to adjust the initial output voltage to the target voltage. The preset voltage is, for example, a voltage employed for load that is supplied by the board power supply. The preset voltage may be preset, or may be obtained by the control chip 2 using an external input/output (I/O) interface. For example, when the initial output voltage is relatively small and the output voltage of the board power supply needs to be increased, the control chip 2 controls the first switch 5 to be on and the second switch 6 to be off. In this case, a voltage at the second connection point increases, an input value of the FB pin of the board power supply increases, and the output voltage of the output pin of the board power supply increases accordingly. For another example, when the initial output voltage is relatively large and the output voltage of the board power supply needs to be reduced, the control chip 2 controls the first switch 5 to be off and the second switch 6 to be on. In this case, a voltage at the second connection point decreases, an input value of the FB pin of the board power supply decreases, and the output voltage of the output pin of the board power supply decreases accordingly.
When the online voltage adjustment circuit for the board power supply is applied to verification in a board power supply development phase, the control chip 2 dynamically adjusts the output voltage of the output pin of the board power supply using an external input interface, such as a management network port, a Universal Serial Bus (USB) port, or a serial port in order to implement a high-low bias test on the output voltage of the board power supply, reduce workload of manually welding the bias resistors, and improve test efficiency in verification.
Generally, in the case of mass production of board power supplies, output voltages of the board power supplies should be adjusted. If R1 and R2 are installed in a manner shown in
When the board power supply is abnormal or the output voltage fluctuates or drifts because of poor welding of peripheral components, online detection is performed and the input value of the FB pin of the board power supply is adjusted to correct the output voltage of the output pin, thereby restoring the output voltage online and reducing a failure of the board power supply caused by a power supply.
In addition, when a voltage range of load that is supplied by the board power supply is relatively large, the output pin may be controlled, based on a size of the load to output different voltage values such that the board power supply works in a load interval with highest conversion efficiency, and power consumption of the load is minimized in a standby mode. For example, it is assumed that a power of the load is P. When P≥70%, it is considered that the board power supply is in a heavy load state, and the output voltage is dynamically adjusted to increase the output voltage, and reduce a current value. When 70%>P≥30%, it is considered that the board power supply is in a half-load state, and the output voltage is dynamically adjusted such that the board power supply outputs a normal voltage value. When 30≥P>5%, it is considered that the board power supply is in a light load state, and the output voltage is dynamically adjusted to reduce the output voltage, and increase a current value, thereby increasing conversion efficiency of the board power supply. When P≤5%, it is considered that the board power supply is in an idle state, and the output voltage is dynamically adjusted to reduce the output voltage such that a current value is close to 0, thereby reducing power consumption of the load in a standby mode.
In the online voltage adjustment circuit for the board power supply that is provided in this embodiment of this application, the first voltage division circuit is connected in parallel to the first bias resistor, the second voltage division circuit is connected in parallel to the second bias resistor, the detection chip obtains the initial output voltage of the board power supply, and finally, based on the initial output voltage and the preset voltage, the control chip controls on/off of the first switch on the first voltage division circuit, and on/off of the second switch on the second voltage division circuit such that an FB value of the FB pin of the board power supply changes, and then the output voltage of the board power supply changes, thereby adjusting the output voltage of the board power supply. In the adjustment process, instead of manually welding the bias resistors, the control chip automatically controls on/off of the first switch and the second switch such that the output voltage of the board power supply changes, thereby reducing complexity of adjustment of the output voltage of the board power supply.
In a feasible implementation, the first voltage division element 3 includes a first voltage division resistor, and the second voltage division element 4 includes a second voltage division resistor. Further, referring to
Referring to
Referring to Table 1, a first switch 5 is denoted as {circle around (1)}, a second switch 6 is denoted as {circle around (2)}, an input value of an FB pin is denoted as an FB value, and the initial output voltage is denoted as Vo. In this case, when the control chip 2 controls the first switch 5 to be off and the second switch 6 to be off, the output voltage of the board power supply remains unchanged, to be specific, the initial voltage is used as the target voltage. When the control chip 2 controls the first switch 5 to be on and the second switch 6 to be off, the FB value of the board power supply increases, and the output voltage also increases. For example, the initial output voltage increases to a first voltage Vo1, and Vo1 is used as the target voltage, and a value of Vo1 is related to the resistance values of R1, R2 and R3. When the control chip 2 controls the first switch 5 to be off and the second switch 6 to be on, the FB value of the board power supply decreases, and the output voltage also decreases. For example, the initial output voltage decreases to a second voltage Vo2, Vo2 is used as the target voltage, and a value of Vo2 is related to the resistance values of R1, R2 and R4.
Referring to
It should be noted that the circuit in
In another feasible implementation, the first voltage division element 3 includes a first digital potentiometer, the second voltage division element 4 includes a second digital potentiometer, and the control chip 2 is further connected to the first digital potentiometer and the second digital potentiometer. Further, referring to
Referring to
Referring to Table 2, a first switch 5 is denoted as {circle around (1)}, a second switch 6 is denoted as {circle around (2)}, Rp1 is denoted as {circle around (3)}, Rp2 is denoted as {circle around (4)}, an input value of an FB pin is denoted as an FB value, and the initial output voltage is denoted as Vo. In this case, when the control chip 2 controls the first switch 5 to be off and the second switch 6 to be off, the output voltage of the board power supply remains unchanged, to be specific, the initial voltage is used as the target voltage. When the control chip 2 controls the first switch 5 to be on and the second switch 6 to be off, the FB value of the board power supply increases, and the output voltage also increases. For example, the initial output voltage increases to a first voltage Vo1, and Vo1 is used as the target voltage, and a value of Vo1 is related to resistance values of Rp1. When the control chip 2 controls the first switch 5 to be off and the second switch 6 to be on, the FB value of the board power supply decreases, and the output voltage also decreases. For example, the initial output voltage decreases to a second voltage Vo2, Vo2 is used as the target voltage, and a value of Vo2 is related to resistance values of Rp2. When the control chip 2 controls the first switch 5 to be on and the second switch 6 to be off, and adjusts Rp1, the FB value of the board power supply dynamically changes, and the output voltage also dynamically changes. For example, the output voltage gradually increases from the initial output voltage to a first voltage Vo1, or gradually decreases from Vo1 to the initial output voltage to obtain a target voltage that is represented as Vo3. Vo3 is between the initial voltage and Vo1, and a value of Vo1 is related to resistance values of Rp1. When the control chip 2 controls the first switch 5 to be off and the second switch 6 to be on, and adjusts Rp2, the FB value of the board power supply dynamically changes, and the output voltage also dynamically changes. For example, the output voltage gradually decreases from the initial output voltage to a second voltage Vo2, or gradually increases from Vo2 to the initial output voltage to obtain a target voltage that is represented as Vo4. Vo4 is between the initial voltage and Vo2, and a value of Vo2 is related to resistance values of Rp2. When the control chip 2 controls the first switch 5 to be on and the second switch 6 to be on, and adjusts Rp1 and Rp2, the FB value of the board power supply dynamically changes, and the output voltage also dynamically changes. For example, the output voltage gradually increases from the initial output voltage to a first voltage Vo1, and gradually decreases from Vo1 to Vo2, and then gradually increases from Vo2 to Vo1 to obtain a target voltage that is represented as Vo5. Vo5 is between Vo2 and Vo1, and values of Vo2 and Vo1 are related to resistance values of Rp1 and Rp2.
Referring to
It should be noted that the circuit in
In the foregoing embodiments, the first switch is a switching transistor or a metal-oxide semiconductor field-effect transistor (MOSFET), and the second switch is a switching transistor or a MOSFET.
Persons of ordinary skill in the art may understand that all or some of the steps of the method embodiments may be implemented by a program instructing related hardware. The program may be stored in a computer-readable storage medium. When the program runs, the steps of the method embodiments are performed. The storage medium includes any medium that can store program code, such as a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), or a flash memory.
Finally, it should be noted that the foregoing embodiments are merely intended for describing the technical solutions of this application, not limiting this application. Although this application is described in detail with reference to the foregoing embodiments, persons of ordinary skill in the art should understand that they may still make modifications to the technical solutions described in the foregoing embodiments or make equivalent replacements to some or all technical features thereof, without departing from the scope of the technical solutions of the embodiments of this application.
Number | Date | Country | Kind |
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201611011162.0 | Nov 2016 | CN | national |
This application is a continuation of International Patent Application No. PCT/CN2017/110878 filed on Nov. 14, 2017, which claims priority to Chinese Patent Application No. 201611011162.0 filed on Nov. 17, 2016. The disclosures of the aforementioned applications are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/CN2017/110878 | Nov 2017 | US |
Child | 16415527 | US |