JP7609992B2 - Voltage calibration circuit and method - Google Patents

Description

Examples of the present application relate to the field of integrated circuit design, and more particularly, but not exclusively, to voltage calibration circuits and methods.

LDO (Low Dropout Regulator) is a linear DC (Direct Current) voltage regulator. That is, LDO is a linear voltage drop type power management chip, and has advantages such as low cost, low noise, and small static current. Therefore, how to easily and effectively calibrate the voltage of an LDO circuit system has become an issue that needs to be solved urgently.

The main technical problem that the voltage calibration circuit and method provided by the embodiments of the present application aim to solve is how to simplify the voltage self-calibration process.

In a first aspect, according to an embodiment of the present application, there is provided a voltage calibration circuit including a reference voltage generation module that acquires a reference voltage based on temperature data and transmits it to a comparator, a comparator that includes a first voltage receiving terminal connected to the reference voltage generation module and a second voltage terminal that receives a voltage to be calibrated, compares the reference voltage with the voltage to be calibrated and obtains a voltage comparison result, and a calibration controller that is connected to a result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage.

The voltage calibration circuit may also include a main circuit connected to the comparator, which acquires the voltage to be calibrated and transmits it to the comparator.

The voltage calibration circuit further includes a counter having a first connection terminal connected to the calibration controller and a second connection terminal connected to the main circuit, receiving a lift control signal transmitted from the calibration controller, and acquiring a count value based on the lift control signal.

The main circuit may also include a calibration determination module connected to the counter, receiving the count value transmitted from the counter, and determining whether or not the calibration operation is to be completed based on the count value; an error amplifier connected to the calibration determination module, which sets the target voltage within a predetermined voltage range when the calibration determination module determines that the calibration operation is completed; and a drive module connected to the error amplifier and generating a current required for the operation of the main circuit.

The reference voltage generation module may include a temperature sensor, an A/D converter, and a reference voltage acquisition unit, the temperature sensor being connected to the A/D converter and collecting and transmitting temperature data to the A/D converter, the A/D converter having a first connection terminal connected to the temperature sensor and a second connection terminal connected to the reference voltage acquisition unit, converting the temperature data into a temperature digital signal and transmitting it to the reference voltage acquisition unit, and the reference voltage acquisition unit having a first connection terminal connected to the A/D converter and a second connection terminal connected to the comparator, acquiring a voltage corresponding to the temperature digital signal as a reference voltage and transmitting it to the comparator.

The voltage calibration circuit may also include a calibration signal generation module connected to the calibration controller and configured to generate a calibration signal for causing the calibration controller to perform a voltage calibration operation.

The calibration signal generation module may also include a first signal generation module, and the calibration controller may have a first signal receiving terminal connected to the first signal generation module and receiving a first signal transmitted from the first signal generation module, the first signal being a calibration signal input by a user.

The calibration signal generation module may also include a second signal generation module, and the calibration controller may further have a second signal receiving terminal connected to the second signal generation module and receiving a second signal transmitted from the second signal generation module when the reference voltage changes.

The calibration signal generation module may further include a third signal generation module, and the calibration controller may further include a third signal receiving terminal connected to the third signal generation module and configured to receive a third signal as a clock signal transmitted from the third signal generation module.

In a second aspect, according to an embodiment of the present application, there is further provided a voltage calibration method applied to the voltage calibration circuit of the first aspect. The method includes obtaining a voltage to be calibrated and a reference voltage, comparing the voltage to be calibrated with the reference voltage to obtain a voltage comparison result, and calibrating the voltage to be calibrated based on the voltage comparison result, the reference voltage being obtained by the reference voltage generation module based on temperature data.

According to the voltage calibration circuit and method provided by the embodiment of the present application, the voltage calibration circuit includes a reference voltage generation module that obtains a reference voltage based on temperature data and transmits it to a comparator, a first voltage receiving terminal connected to the reference voltage generation module, and a second voltage terminal that receives the voltage to be calibrated, and includes a comparator that compares the reference voltage with the voltage to be calibrated to obtain a voltage comparison result, and a calibration controller that is connected to the result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage. The present invention can realize self-calibration of voltage more simply and effectively by combining a reference voltage generation module, a comparator, and a calibration controller.

Other features and corresponding advantages of the present invention will be described later in the specification, but it should be understood that at least some of the advantages will be apparent from the description of the present invention in the specification.

FIG. 2 is a schematic diagram of a voltage calibration circuit provided according to an embodiment of the present application. FIG. 2 is a schematic diagram of a calibration controller in a voltage calibration circuit provided according to an embodiment of the present application. FIG. 2 is a schematic diagram of a voltage calibration circuit provided according to another embodiment of the present application. FIG. 2 is a schematic diagram of a main circuit in a voltage calibration circuit provided by another embodiment of the present application. FIG. 2 is a schematic diagram of a specific voltage calibration circuit provided by another embodiment of the present application. FIG. 13 is a schematic diagram of different signal acquisitions in an exemplary voltage calibration circuit provided by another embodiment of the present application. FIG. 2 is a schematic diagram of a specific voltage calibration circuit provided according to yet another embodiment of the present application. 4 is a method flow chart of a voltage calibration method provided by an embodiment of the present application.

In order to more clearly explain the technical solutions of the embodiments of the present application, the following will briefly explain the accompanying drawings required for the description of the embodiments. It is obvious that the accompanying drawings described below are merely some embodiments of the present application, and those skilled in the art can obtain other accompanying drawings from these accompanying drawings without performing creative labor.

In conventional FPGAs (Field Programmable Gate Arrays), there are various means for adjusting voltages. However, in conventional voltage trimming methods, it is necessary to input predetermined trimming information according to test results during calibration, and then voltage trimming can be realized according to the number of bits that can be trimmed. However, these trimming methods complicate the test vector, which increases the cost required for testing to a certain extent. In other words, in conventional voltage trimming methods, different trimming needs to be performed according to environmental factors such as temperature, and when more precise adjustment and control are required, they are usually affected by the circuit process. That is, conventional voltage trimming methods have design limitations and cannot achieve better self-calibration.

In response to the above problems, the present inventors have proposed a voltage calibration circuit and method provided by the embodiments of the present application. According to the embodiments of the present application, the reference voltage generation module, the comparator, and the calibration controller simplify the conditions for achieving voltage self-calibration, and reduce the requirements for voltage self-calibration to a certain extent.

Referring to FIG. 1, a voltage calibration circuit provided by an embodiment of the present application is shown. The voltage calibration circuit 100 may include a reference voltage generation module 110, a comparator 120, and a calibration controller 130.

In an embodiment, the reference voltage generation module 110 obtains a reference voltage based on the temperature data and transmits it to the comparator 120. The voltage calibration circuit 100 in an embodiment of the present invention may be a linear low-voltage differential regulator (LDO).

In one embodiment, the comparator 120 includes a first voltage receiving terminal 121 connected to the reference voltage generating module 110 and a second voltage receiving terminal 122 for receiving a voltage to be calibrated. At the same time, the comparator 120 may compare the reference voltage with the voltage to be calibrated to obtain a voltage comparison result. The voltage to be calibrated is also referred to as an LDO actual voltage.

In an embodiment, when the comparator 120 receives the reference voltage and the voltage to be calibrated transmitted from the first voltage receiving terminal 121 and the second voltage receiving terminal 122, the comparator 120 may compare the reference voltage with the voltage to be calibrated to obtain a voltage comparison result. Specifically, the comparator 120 may determine whether the voltage to be calibrated is greater than the reference voltage. If the comparator 120 determines that the voltage to be calibrated is greater than the reference voltage, the comparator 120 outputs a voltage comparison result that is 1. According to an embodiment of the present invention, the voltage comparison result that is 1 may be transmitted to the calibration controller 130 as an elevation control signal to instruct the calibration controller 130 to lower the voltage to be calibrated.

In another aspect, the comparator 120 outputs a voltage comparison result of 0 when it is determined that the voltage to be calibrated is smaller than the reference voltage. According to an embodiment of the present invention, the voltage comparison result of 0 can be sent to the calibration controller 130 as an increase/decrease control signal to instruct the calibration controller 130 to increase the voltage to be calibrated. When calibrating the voltage to be calibrated, the calibration controller 130 can perform calibration according to a predetermined voltage. For example, when it is determined that the voltage to be calibrated V _out is smaller than the reference voltage V _ref , the calibration controller 130 can increase the voltage to be calibrated V _out by a predetermined voltage value O during calibration. Each time calibration is performed, the value of the voltage to be calibrated V _out increases, and the voltage after calibration is equal to the voltage to be calibrated V _out +O. Also, when it is determined that the voltage to be calibrated is equal to the reference voltage, the voltage calibration circuit may stop the voltage calibration operation.

During calibration, the predetermined voltage value can be kept constant, i.e., the voltage value increased or decreased each time calibration is performed can be the same. For example, if the voltage to be calibrated _Vout is 3V and the reference voltage _Vref is 4V, the predetermined voltage value O can be set to 0.2. That is, each time the voltage to be calibrated Vout is calibrated, the voltage to be calibrated _Vout is increased by 0.2V. During calibration, the predetermined voltage value O is kept constant. At this time, the voltages to be calibrated _Vout obtained are 3.2V, 3.4V, 3.6V, 3.8V, and 4.0V.

In other embodiments, the predetermined voltage value may be variable, i.e., the predetermined voltage value may be decremented during voltage calibration. For example, the predetermined voltage value O may be 0.5 V during the first calibration, 0.4 V during the second calibration, and 0.3 V during the third calibration.

Also, according to the embodiment of the present invention, when calibrating the voltage to be calibrated, it is also possible to calibrate the voltage to be calibrated with the maximum predetermined voltage value O at the start of calibration. If the relationship between the voltage to be calibrated and the reference voltage does not match the predetermined relationship, the predetermined voltage value can be reduced. For example, if the voltage to be calibrated V _out is 3V and the reference voltage V _ref is 4V, the maximum predetermined voltage value O can be set to 0.4V. Since the voltage to be calibrated V _out is smaller than the reference voltage V _ref , the voltage to be calibrated V _out obtained at this time is 3.4V and 3.8V, respectively, and in the third calibration, it becomes 3.8V + 0.4 = 4.2, which is obviously larger than 4V. In this case, instead of performing calibration using the maximum predetermined voltage value, the maximum predetermined voltage value can be reduced. For example, the maximum predetermined voltage value O can be halved to 0.2V. At this time, by adding the predetermined voltage value to the latest voltage to be calibrated, a value that is exactly 4V can be obtained. In this manner, the calibration controller 130 can improve the speed of voltage calibration.

In another aspect, the calibration controller 130 is connected to the result output terminal 123 of the comparator 120, and can calibrate the voltage to be calibrated based on the voltage comparison result transmitted from the comparator 120 to obtain the target voltage.

In another embodiment, in order to more clearly understand the structure of the calibration controller 130, the embodiment of the present invention provides a schematic diagram shown in FIG. 2. As can be seen from FIG. 2, in addition to the reference voltage generation module 110, the comparator 120, and the calibration controller 130, the voltage calibration circuit 100 may further include a calibration signal generation module 140 connected to the calibration controller 130 and generating a calibration signal for causing the calibration controller 130 to perform a voltage calibration operation.

In an embodiment, the calibration signal generating module 140 may include a first signal generating module 141. The calibration controller 130 has a first signal receiving terminal connected to the first signal generating module 141 and receiving a first signal transmitted from the first signal generating module 141, the first signal being a calibration signal input by a user. The first signal is also referred to as a forced calibration signal. Note that the first signal may be a forced calibration command transmitted by a chip without being restricted by the voltage calibration circuit. That is, the first signal generating module 141 may be a part of the voltage calibration circuit 100, or may be a chip independent of the voltage calibration circuit 100.

As another aspect, the calibration signal generation module 140 may include a second signal generation module 142. The calibration controller 130 further has a second signal receiving terminal connected to the second signal generation module 142 and receiving a second signal transmitted from the second signal generation module 142 when the reference voltage changes. The second signal is also referred to as a state change signal, which mainly refers to a reference voltage change signal. That is, when the reference voltage signal changes, the second signal is transmitted as 1 to the calibration controller 130, instructing the calibration controller 130 to perform a voltage calibration operation.

Furthermore, the reference voltage typically changes with temperature. That is, when the temperature changes, the second signal generating module 142 generates and transmits a second signal to the calibration controller 130 to instruct the calibration controller 130 to calibrate the output voltage of the voltage calibration circuit 100 according to the latest reference voltage. In other words, the second signal may be responsive to the calibration controller 130 monitoring the change in the reference voltage, and when the reference voltage changes, the second signal is activated, causing the calibration controller 130 to perform a calibration operation.

In another embodiment, the calibration signal generation module 140 may include a third signal generation module 143. The calibration controller 130 further has a third signal receiving terminal connected to the third signal generation module 143 and receiving the third signal as a clock signal transmitted from the third signal generation module 143. According to an embodiment of the present invention, a recalibration command is automatically transmitted every M+1 clock cycles after the calibration by the voltage calibration circuit is completed. That is, the third signal generation module 143 transmits a third signal every M+1 clock cycles, and the third signal can instruct the calibration controller to perform a voltage calibration operation.

In an embodiment, the calibration controller 130 performs a voltage calibration operation when it receives any one of the first signal, the second signal, and the third signal. That is, when a certain clock period elapses, when a calibration command is forcibly input from the outside, or when a calibration reference condition changes, the calibration controller 130 performs a voltage calibration operation. The calibration reference condition may be whether or not the reference voltage has changed, whether or not the comparison condition has changed, whether or not the current environment has changed, and the like. It can be clearly understood from FIG. 2 that the first signal, the second signal, and the third signal satisfy a logical relationship of "OR".

The reference voltage in the embodiment of the present invention may be fixed or may constantly change. That is, when the temperature of the environment in which the voltage calibration circuit is placed changes, the reference voltage changes accordingly. The reference voltage may also be acquired while being constantly calibrated based on the reference voltage that is actually output. That is, the reference voltage may also be acquired while being constantly calibrated. The calibration process of the reference voltage is similar to the calibration process of the voltage to be calibrated, so a detailed description will be omitted here.

According to the voltage calibration circuit provided by the embodiment of the present application, the voltage calibration circuit includes a reference voltage generation module that acquires a reference voltage based on temperature data and transmits it to a comparator, a first voltage receiving terminal connected to the reference voltage generation module, and a second voltage terminal that receives a voltage to be calibrated. The voltage calibration circuit includes a comparator that compares the reference voltage with the voltage to be calibrated to obtain a voltage comparison result, and a calibration controller that is connected to the result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage. The present invention can realize self-calibration of voltage more simply and effectively by combining a reference voltage generation module, a comparator, and a calibration controller. In addition, since the calibration controller in the embodiment of the present application can receive multiple signals, it not only facilitates background calibration of the LDO system to a certain extent, but also allows foreground calibration by different control commands (signals). In this way, calibration and control of logic clock resources can be performed more simply and effectively by FPGA.

Referring to FIG. 3, a voltage calibration circuit provided according to another embodiment of the present application is shown. The voltage calibration circuit 200 may include a reference voltage generation module 210, a main circuit 220, a comparator 230, and a calibration controller 240.

In an embodiment, the main circuit 220 may be connected to a comparator 230 to obtain a voltage to be calibrated and send it to the comparator 230. The main circuit 220 in the embodiment of the present invention is also referred to as an LDO. The main circuit 220 mainly performs some basic operations of the voltage calibration circuit, such as voltage stabilization and driving operations.

In another embodiment, the main circuit 220 may include a calibration determination module 221, an error amplifier 222, and a driving module 223. The relationship between the calibration determination module 221, the error amplifier 222, and the driving module 223 is shown in FIG. 4. As can be seen from FIG. 4, the calibration determination module 221 is connected to the counter 250, receives the count value transmitted from the counter 250, and determines whether the calibration operation is terminated based on the count value.

The error amplifier 222 may be connected to the calibration determination module 221, and when the calibration determination module 221 determines that the calibration operation is completed, the target voltage may be set to within a predetermined voltage range. The drive module 223 is connected to the error amplifier 222 and generates a current required for the operation of the main circuit 220.

The reference voltage generation module 210 may be installed outside the main circuit 220 or directly in the main circuit. Alternatively, the reference voltage generation module 210 may not be installed in the voltage calibration circuit 200. In this case, the calibration controller 340 may also function as the reference voltage generation module 310. When it is simply necessary to input a reference voltage code value from the outside, a test vector is usually created externally, and the code value is scanned to select and store an appropriate reference voltage code value. In other words, the embodiment of the present invention can directly receive the reference voltage by the calibration controller 340. That is, the reference voltage can be directly input by the user through an interface. The calibration controller 340 can perform operations such as comparison and calibration on the received voltage to be calibrated and the reference voltage. In this way, the design of the test vector can be simplified, and the cost of testing can be reduced to a certain extent.

As can be seen from the above description, the reference voltage generation module 210 mainly generates a reference voltage. The reference voltage is an LDO reference voltage value required in the current environment. This reference voltage value is input from the outside and stored in the circuit, and is required to be preserved in the circuit even if the chip runs out of battery. In different environments, the sensing and monitoring module in the voltage calibration circuit can monitor the current environment and feed back the monitored information to the reference voltage generation module 210, and sample the corresponding LDO reference voltage value as a reference amount for LDO calibration in the current environment. The current environment may include the physical environment and the specific application of the chip, etc.

In addition, the reference voltage generation module in the embodiment of the present invention may be installed in the main circuit 220 or may be installed independently of the main circuit 220. In addition, a voltage trimming unit that is used in a tester to realize voltage trimming before a product corresponding to the voltage calibration circuit 200 is completed may be installed separately in the main circuit 220. That is, the voltage trimming unit is a circuit that mainly calibrates the voltage to be calibrated in the test stage, and the calibration controller is a circuit that calibrates the voltage to be calibrated after a product corresponding to the voltage calibration circuit 200 is completed.

In another embodiment, the voltage calibration circuit 200 further includes a counter having a first connection terminal 251 connected to the calibration controller 240 and a second connection terminal 252 connected to the main circuit 220, receiving a lift control signal transmitted from the calibration controller 240, and acquiring a count value based on the lift control signal. The counter 250 may also be connected to the calibration determination module 221 of the main circuit 220, acquiring a count value, transmitting the count value to the calibration determination module 221, and instructing the calibration determination module 221 to determine whether or not to stop the voltage calibration operation based on the count value.

In order to more clearly understand the relationship between the reference voltage generation module 210, the main circuit 220, the comparator 230, the calibration controller 240 and the counter 250, the embodiment of the present invention provides a configuration block diagram shown in FIG. 5. As can be seen from FIG. 5, the voltage calibration circuit 200 may not include the reference voltage generation module 210. If the reference voltage generation module 210 is not included, the embodiment of the present invention can directly receive the reference voltage input from the outside through the first voltage receiving terminal of the comparator 230. When the selection switch 260 is connected to the first voltage receiving terminal, the calibration controller 240 can calibrate the reference voltage. On the other hand, when the selection switch 260 is connected to the second voltage receiving terminal, the calibration controller 240 can calibrate the voltage to be calibrated.

In addition, when the selection switch 260 receives a step control signal that is 1, it can calibrate the voltage to be calibrated, and when it receives a step control signal that is 0, it can calibrate the reference voltage. The step control signal may be input by a user or may be output by the voltage calibration circuit according to the actual situation, and the specific way of inputting it is not explicitly limited here and can be selected according to the actual situation. Therefore, an embodiment of the present invention can realize both the calibration of the reference voltage to be calibrated and the calibration of the reference voltage.

In another embodiment, the calibration controller 240 can receive a clock signal, which can be a clock 1, and an external control signal, which can be at least one of the first signal, the second signal, and the third signal mentioned in the above embodiment. The calibration controller 240 can obtain a lift control signal when calibrating the voltage according to the voltage comparison result output by the comparator 230. Then, the calibration controller 240 can send the lift control signal to the counter 250. At the same time, the calibration controller 240 can also send a pause/start count signal, a reset signal, an input signal, etc., to the counter 250, which have a relationship as shown in FIG. 6.

In one specific embodiment, when the voltage to be calibrated is higher than the reference voltage, the output of the comparator 230 is 1, and the up/down control signal is 1, so that the counter is controlled to count down, thereby lowering the reference voltage. When the voltage to be calibrated is lower than the reference voltage, the output of the comparator 230 is 0, and the up/down control signal is 0, so that the counter is controlled to count up, thereby raising the reference voltage. For example, if the voltage to be calibrated V _out is 3V, the reference voltage V _ref is 4V, and the predetermined voltage value O is 0.2, the voltage to be calibrated needs to be calibrated five times, and during the calibration, the values of the counter are 1, 2, 3, 4, 5, and 6, respectively, and it can be seen that the value of the counter is incremented. Note that, the counter can receive an initial count inputted according to a predetermined or actual situation by the user during counting. For example, if the initial count value inputted by the user is 7, the obtained count values are 7, 8, 9, 10, 11, and 12, respectively.

In an embodiment, when the voltage to be calibrated is adjusted close to the reference voltage, the output of the comparator 230 becomes a square wave that changes between 0 and 1 at approximately the same frequency as the clock 1. At this time, the comparator 230 generates at least N or N+1 0 and 1 changes in succession, triggering a calibration completion signal. Also, according to an embodiment of the present invention, the voltage to be calibrated can be made slightly higher than the reference voltage after the calibration is completed.

In another embodiment, when the calibration operation is completed, the counter 250 stops counting, holds the current count value, and calibrates the voltage to be calibrated according to the count value. Also, as shown in FIG. 2, the calibration controller 240 can release the reset signal 1 during the calibration and perform a reset operation with the reset signal 2. During the calibration operation, the calibration controller 240 can automatically lower the calibration signal without disturbing the calibration process. When the calibration is completed, a reset operation is performed with the reset signal 1, the automatic calibration operation is completed, the reset signal 2 is released, and the circuit starts preparing for M+1 clock cycles and generates an automatic calibration command. This allows the automatic calibration to be repeated.

According to the voltage calibration circuit provided by the embodiment of the present application, the voltage calibration circuit includes a reference voltage generation module that acquires a reference voltage based on temperature data and transmits it to a comparator, a first voltage receiving terminal connected to the reference voltage generation module, and a second voltage terminal that receives the voltage to be calibrated. The voltage calibration circuit includes a comparator that compares the reference voltage with the voltage to be calibrated to acquire a voltage comparison result, and a calibration controller that is connected to the result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to acquire a target voltage. The present invention can realize self-calibration of voltage more simply and effectively by combining the reference voltage generation module, the comparator, and the calibration controller. Also, according to the embodiment of the present application, by providing a main circuit, the voltage to be calibrated can be supplied to the voltage calibration circuit. Also, by providing a counter, not only can the voltage calibration circuit be simplified, but also timing confusion can be avoided and clock frequency restrictions can be relaxed.

Referring to FIG. 7, a voltage calibration circuit provided by yet another embodiment of the present application is shown. The voltage calibration circuit 300 can include a reference voltage generation module 310, a main circuit 320, a comparator 330, a calibration controller 340, and a counter 350. The reference voltage generation module 310 includes a temperature sensor 311, an A/D converter 312, and a reference voltage acquisition unit 313.

In an embodiment, the temperature sensor 311 is connected to the A/D converter 312, and collects and transmits temperature data to the A/D converter 312. In addition, the A/D converter 312 may have a first connection terminal 3121 connected to the temperature sensor 311 and a second connection terminal 3122 connected to the reference voltage acquisition unit 313, and may convert the temperature data into a temperature digital signal and transmit it to the reference voltage acquisition unit 313.

According to an embodiment of the present invention, a digital code value representing the current chip temperature can be obtained using a temperature sensor 311 and an A/D converter 312 (ADC) in the FPGA. This digital code value functions as a pointer to a non-volatile memory, and can be written with a control code value corresponding to the LDO voltage required at that temperature according to the memory location it points to. When calibrating the voltage to be calibrated, LDO standard reference voltages at different temperatures can be called and the LDO standard reference voltage corresponding to the current temperature can be used as the reference voltage. In other words, the reference voltage generation module 310 can generate a digital code representing the current temperature using the temperature sensor 311 and the A/D converter 312. Then, the reference voltage acquisition unit 313 can perform addressing using the acquired temperature digital code to acquire a digital code value corresponding to the reference voltage, and use the voltage corresponding to this digital code value as the reference voltage.

In one embodiment, the reference voltage acquisition unit 313 has a first connection terminal 3131 connected to the A/D converter and a second connection terminal 3132 connected to the comparator 330, and acquires a voltage corresponding to the temperature digital signal as a reference voltage and transmits it to the comparator 330.

As can be seen from the above description, when the comparator 330 obtains the voltage to be calibrated and the reference voltage, it compares the voltage to be calibrated with the reference voltage. If the voltage to be calibrated is greater than the reference voltage, the calibration controller 340 lowers the voltage to be calibrated according to the process, and then compares again whether the lowered voltage to be calibrated is greater than the calibration reference voltage. If the voltage to be calibrated is greater than the calibration reference voltage, the voltage to be calibrated can be further lowered according to the process. Also, if the voltage to be calibrated is lower than the reference voltage, the calibration controller 340 can increase the voltage to be calibrated.

Note that if the voltage to be calibrated is successively increased and decreased in successive adjustment steps during calibration of the voltage to be calibrated, this indicates that the current calibration has reached a state closest to the reference voltage, and at this point it can be determined that the current voltage calibration operation is complete. This allows background calibration of the LDO system to be realized, while at the same time allowing foreground calibration, which can be easily controlled by the abundant logic clock resources of the FPGA, to be performed by a control command.

According to the voltage calibration circuit provided by the embodiment of the present application, the voltage calibration circuit includes a reference voltage generation module that obtains a reference voltage based on temperature data and transmits it to a comparator, a first voltage receiving terminal connected to the reference voltage generation module, and a second voltage terminal that receives the voltage to be calibrated, and includes a comparator that compares the reference voltage with the voltage to be calibrated to obtain a voltage comparison result, and a calibration controller that is connected to the result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage. The present invention can realize self-calibration of voltage more simply and effectively by combining the reference voltage generation module, the comparator, and the calibration controller. Furthermore, according to the embodiment of the present invention, not only can the voltage to be calibrated be flexibly calibrated using the abundant logic clock resources of the FPGA, but also the hardware cost can be reduced to a certain extent.

Refer to FIG. 8, which is a method flowchart of a voltage calibration method provided by an embodiment of the present application, which is applied to the voltage calibration circuit described above. As can be seen from FIG. 8, the method includes steps S410 to S430.

In step S410, the voltage to be calibrated and a reference voltage are obtained, and the reference voltage is obtained by the reference voltage generation module based on the temperature data.

In step S420, the voltage to be calibrated is compared with the reference voltage to obtain a voltage comparison result.

In step S430, the voltage to be calibrated is calibrated based on the voltage comparison result.

According to the embodiment of the present invention, there is no need to rely too heavily on the temperature characteristic curve of the reference voltage itself during voltage calibration, allowing some freedom in design margin. This means can be used in various applications where the LDO voltage needs to be changed according to the environment settings, and can achieve relatively accurate control of the LDO voltage during background and foreground voltage calibration, not only mitigating the overshoot of the LDO voltage, but also improving the voltage recovery speed and optimizing the load adjustment rate. By using an FPGA, the voltage calibration circuit does not require excessive hardware design costs, and can implement built-in self testing (BIST) for the chip.

As described above, according to the voltage calibration circuit and method provided by the embodiment of the present application, the voltage calibration circuit can be used to more simply and efficiently calibrate the voltage. The voltage calibration circuit includes a reference voltage generation module that acquires a reference voltage based on temperature data and transmits it to a comparator, a first voltage receiving terminal connected to the reference voltage generation module, and a second voltage terminal that receives the voltage to be calibrated, and includes a comparator that compares the reference voltage with the voltage to be calibrated to obtain a voltage comparison result, and a calibration controller that is connected to the result output terminal of the comparator and calibrates the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage. The present invention can more simply and effectively achieve self-calibration of voltage by combining a reference voltage generation module, a comparator, and a calibration controller. Furthermore, according to the embodiment of the present application, the function of the reference voltage generation module can be also achieved by simply introducing a reference voltage from outside, thereby improving the flexibility of voltage calibration.

As can be seen, those skilled in the art will appreciate that all or some of the steps of the methods, systems, and functional modules/units in the systems disclosed above may be implemented as software (which may be implemented by computer program code executable by a computing system), firmware, hardware, and appropriate combinations thereof. In hardware embodiments, the division between the functional modules/units mentioned in the above description does not necessarily correspond to the division of physical assemblies, for example, one physical assembly may have multiple functions, or one function or step may be performed by several physical assemblies in cooperation. Some or all of the physical assemblies may be implemented as software executed by a processor such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit such as an application specific integrated circuit.

Furthermore, those skilled in the art will appreciate that communication media typically include computer-readable instructions, data structures, computer program modules, or other data in a modulated data signal, such as a carrier wave or other transmission mechanism, and may include any information transmission medium. Thus, the present application is not limited to any particular combination of hardware and software.

The above is a more detailed explanation of the examples of the present application together with specific embodiments, and it should not be recognized that the specific implementation of the present application is limited to these descriptions. A person skilled in the art to which the present application pertains may make some simple deductions or substitutions without departing from the inventive concept of the present application, and all of them should be considered to fall within the scope of protection of the present application.

This application claims priority to a prior Chinese application entitled "Voltage Calibration Circuit and Method" filed on December 31, 2020, with application number 202011627543.8, the contents of which are incorporated herein by reference.

Claims (4)

1. A voltage calibration circuit, comprising:
a reference voltage generating module for obtaining a reference voltage based on temperature data and sending the reference voltage to a comparator;
a comparator including a first voltage receiving terminal connected to the reference voltage generating module and a second voltage receiving terminal for receiving a voltage to be calibrated, the comparator being configured to compare the reference voltage with the voltage to be calibrated to obtain a voltage comparison result;
a calibration controller connected to a result output terminal of the comparator, for calibrating the voltage to be calibrated based on the voltage comparison result transmitted from the comparator to obtain a target voltage;
a calibration signal generating module coupled to the calibration controller, the calibration signal generating module generating a calibration signal for causing the calibration controller to perform a voltage calibration operation;
a main circuit connected to the comparator, for acquiring a voltage to be calibrated and sending it to the comparator;
a counter having a first connection terminal connected to the calibration controller and a second connection terminal connected to the main circuit, for receiving a lift control signal sent from the calibration controller and obtaining a count value based on the lift control signal;
Including,
the calibration controller transmits a first reset signal or a second reset signal which is an inverted signal of the first reset signal to the counter, releases the first reset signal while calibrating the voltage to be calibrated, and executes a reset operation with the second reset signal, and when the calibration is completed, releases the second reset signal, and executes a reset operation with the first reset signal;
The calibration signal generation module includes a second signal generation module;
the calibration controller has a second signal receiving terminal connected to the second signal generating module and configured to receive a second signal, which is a calibration signal transmitted from the second signal generating module when the reference voltage is changed;
The calibration signal generating module includes a third signal generating module;
The calibration controller further includes a third signal receiving terminal connected to the third signal generating module and configured to receive a third signal as a clock signal that is a calibration signal transmitted from the third signal generating module;
The third signal generating module generates the third signal when the first reset signal performs a reset operation and the first reset signal is released.
Including,
1. A voltage calibration circuit comprising: The reference voltage generating module includes a temperature sensor, an A/D converter, and a reference voltage acquiring unit;
The temperature sensor is connected to the A/D converter to collect and transmit temperature data to the A/D converter;
the A/D converter has a first connection terminal connected to the temperature sensor and a second connection terminal connected to the reference voltage acquisition unit, converts the temperature data into a temperature digital signal, and transmits the temperature digital signal to the reference voltage acquisition unit;
the reference voltage acquisition unit has a first connection terminal connected to the A/D converter and a second connection terminal connected to the comparator, and acquires a voltage corresponding to the temperature digital signal as a reference voltage and transmits it to the comparator;
2. The voltage calibration circuit according to claim 1 . The calibration signal generation module includes a first signal generation module;
the calibration controller has a first signal receiving terminal connected to the first signal generating module and configured to receive a first signal transmitted from the first signal generating module, the first signal being a calibration signal input by a user;
2. The voltage calibration circuit according to claim 1 . A voltage calibration method applied to the voltage calibration circuit according to any one of claims 1 to 3 , comprising:
Obtaining a voltage to be calibrated and a reference voltage;
comparing the voltage to be calibrated with the reference voltage to obtain a voltage comparison result;
calibrating the voltage to be calibrated based on a result of the voltage comparison;
During the calibration of the voltage to be calibrated, a first reset signal is released and a reset operation is performed with a second reset signal, and when the calibration is completed, the second reset signal is released and a reset operation is performed with the first reset signal;
When the reference voltage is changed, a voltage calibration is performed using a second signal that is a calibration signal;
When the first reset signal performs a reset operation and the first reset signal is released, a third signal is generated as a clock signal that is a calibration signal, and a voltage calibration operation is performed by the third signal;
Including,
The reference voltage is obtained by the reference voltage generating module based on temperature data.
A voltage calibration method comprising:

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