TW201909557A - Voltage monitoring circuit and voltage monitoring method - Google Patents

Abstract

A voltage monitoring circuit includes a first multiplexer, a controller, a resistor-network circuit and a first comparison circuit. The first multiplexer receives a plurality of first subject voltages. The controller controls the first multiplexer to output one of the plurality of first subject voltages and generates a testing signal. The testing signal includes a plurality of potentials. The controller is configured to output the plurality of potentials switching according to a switch command. The resistor-network circuit is configured to sequentially generate a plurality of first reference voltages according to switching of the plurality of potentials. The first comparison circuit is configured to sequentially compare each of the plurality of first reference voltages to the first subject voltage for sequentially outputting a plurality of first comparing results and sending the plurality of first comparing results to the controller so that a voltage value of the first subject voltage is determined.

Description

Voltage monitoring circuit and voltage monitoring method

The invention relates to a voltage monitoring circuit and a voltage monitoring method, in particular to a voltage monitoring circuit and a voltage monitoring method for applying a power group network.

Analog Digital Converter (ADC) is a commonly used circuit used to convert analog signals into digital signals. In the design of the server, the ADC circuit is often used to monitor the voltage of each channel in the server, or to identify different board ID voltages. In the case of an existing ADC circuit, an integrated circuit bus (I2C) type ADC chip is usually used, and a CPLD differential port can also be used to design an ADC-equipped conversion circuit using the RC integration principle.

However, if an I2C type ADC chip is used, the cost is higher, and if the CPLD differential port is used, the conversion circuit designed according to the ADC's integral comparator principle is limited by the nonlinear characteristics of the RC circuit and the CPLD. The error of the port potential comparator results in a greatly reduced practical accuracy.

The invention provides a voltage monitoring circuit and a voltage monitoring method, which combines a resistance weight network and a voltage comparator, and is matched with a multi-switching architecture, thereby forming a low cost, good stability and occupying only a small amount of output/input port resources. Voltage monitoring circuit.

According to an embodiment of the invention, a voltage monitoring circuit includes a first multiplexer, a controller, a resistor network circuit, and a first comparison circuit. The first multiplexer has a plurality of inputs, outputs and controls. Each input of the first multiplexer receives a corresponding one of the plurality of first measured voltages. The controller is electrically connected to the control end of the first multiplexer. The controller controls the first multiplexer to output one of the first measured voltages at an output end of the first multiplexer through a control end of the first multiplexer, and the controller generates a detection signal. The detection signal includes a plurality of potentials, and the controller has a component for outputting the potentials that are switched in accordance with a switching instruction of the controller. The resistor network circuit includes a plurality of first resistors, and one end of the first resistors is connected to the controller for respectively receiving the potentials of the detection signals. The resistor network circuit is configured to sequentially generate the plurality of first reference voltages according to the switching of the potentials. The first comparison circuit has a first input, a second input, and an output. The first input end of the first comparison circuit is electrically connected to the output end of the first multiplexer, and the second input end of the first comparison circuit is electrically connected to the resistance network circuit. The first comparison circuit is configured to compare the first reference voltages with the outputted first measured voltages in sequence, to sequentially generate a plurality of first comparison results, and sequentially pass the first comparison results The output of the first comparison circuit is transmitted to the controller to determine a voltage value of the first measured voltage, wherein each of the first comparison results has potential information.

According to an embodiment of the invention, a voltage monitoring method is disclosed, which is suitable for a voltage monitoring circuit. The voltage monitoring method includes the steps of controlling the multiplexer to output one of a plurality of measured voltages according to a control command from the controller. Then, according to the switching instruction from the controller, the plurality of potentials included in the detection signal generated by the controller are switched, and the comparison program is repeatedly executed in order to generate a plurality of comparison results, and the number of repeated executions is k times. The receiver determines the voltage value of the measured voltage based on the comparison results. The comparison program includes the following steps: when the potentials are switched for the ith, the reference voltage is generated according to the potentials of the i-th switching, k is an integer greater than 3, and i is less than k and greater than or equal to 0. The integer. Next, the reference voltage and the measured voltage are compared. The switching of the potentials includes switching at least one of the potentials from a high level to a low level or from a low level to a high level.

In summary, in the voltage monitoring circuit and the voltage monitoring method proposed by the present invention, the multi-switching architecture of the multiplexer is matched with the combination of the resistance weight network and the voltage comparison circuit to enable multiple potential switching. The generated plurality of reference voltages can be compared with the measured voltage through the voltage comparison circuit, so that the controller of the voltage monitoring circuit can sequentially measure the voltage values of the plurality of channels in the server, thereby realizing the voltage of each channel of the server. Measure the stability of the process and reduce the resources that occupy the controller's output/input ports.

Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

The detailed features and advantages of the present invention are set forth in the Detailed Description of the Detailed Description of the <RTIgt; </ RTI> <RTIgt; </ RTI> </ RTI> </ RTI> <RTIgt; The objects and advantages associated with the present invention can be readily understood by those skilled in the art. The following examples are intended to describe the present invention in further detail, but are not intended to limit the scope of the invention.

Please refer to FIG. 1. FIG. 1 is a circuit diagram of a voltage monitoring circuit according to an embodiment of the invention. As shown in FIG. 1, the voltage monitoring circuit 1 includes a first multiplexer 10, a controller 12, a resistor network circuit 14, and a first comparison circuit 16. The first multiplexer 10 has a plurality of input terminals I101 to I108, an output terminal R1 and a control terminal C1. Each input end of the first multiplexer 10 receives a corresponding one of the plurality of first measured voltages V1 V V8. For example, the input terminal I101 receives the first measured voltage V1, the input terminal I102 receives the first measured voltage V2, the input terminal I103 receives the first measured voltage V3, and the like, and so on. In practice, the plurality of first measured voltages V1 V V8 are derived from voltages of a plurality of channels to be tested in the server. The controller 12 is electrically connected to the control terminal C1 of the first multiplexer 10. The controller 12 controls the first multiplexer 10 to output one of the first measured voltages V1 VV8 at the output terminal R1 through the control terminal C1 of the first multiplexer 10. The controller 12 can generate a detection signal VT, and the detection signal VT includes a plurality of potentials. In this embodiment, the controller 12 has a component 121 for outputting the potentials that are switched in accordance with the switching command of the controller 12. In practice, the plurality of potentials are presented at high and low potentials (high potential: 1; low potential: 0). In one embodiment, the switching of the plurality of potentials includes switching at least one of the potentials from a high potential to a low potential or from a low potential to a high potential. For example, the switching instruction of the controller 12 can sequentially switch multiple potentials from 00000000 to 11111111. In one example, the controller 12 can be a Complex Programmable Logic Device (CPLD), but the invention is not limited thereto.

Please refer to FIG. 2, which is a detailed circuit diagram of the voltage monitoring circuit according to the embodiment of FIG. 1 of the present invention. The resistor network circuit 14 includes a plurality of first resistors 141-148. One ends of the first resistors 141 148 148 are connected to the controller 12 for respectively receiving the potentials P1 pp P8 included in the detection signal VT. The resistor network circuit 14 is configured to sequentially generate a plurality of first reference voltages according to the switching of the potentials. Further, as shown in FIG. 2, the first comparison circuit 16 has a comparator 161, a resistor 163, and a capacitor 165. The first comparison circuit 16 has a first input terminal I161, a second input terminal I162 and an output terminal R163. The first input terminal I161 of the first comparison circuit 16 is electrically connected to the output terminal R1 of the first multiplexer 10, and the second input terminal I162 of the first comparison circuit 16 is electrically connected to the resistor network circuit 14. The first comparison circuit 16 is configured to sequentially compare the plurality of first reference voltages with the first measured voltage outputted by the output terminal R1, to sequentially generate a plurality of first comparison results, and sequentially The first comparison result is transmitted to the controller 12 through the output terminal R163 of the first comparison circuit 16, and the voltage value of the first measured voltage outputted by the output terminal R1 is determined, wherein each first comparison result has a potential News.

In an embodiment, as shown in FIG. 2, the resistor network circuit 14 further includes a second resistor 149 and an operator 140. The second resistor 149 has a first end T1 and a second end T2. The arithmetic unit 140 has a first end I141, a second end I142, and a third end R143. The first end I141 of the computing device 140 is electrically connected to the other ends of the first resistors 141-148. The second end of the computing device 140 is electrically connected to the first end T1 of the second resistor 149 and the third end of the computing unit 140. R143, the plurality of first reference voltages are output by the second end of the second resistor 149, wherein the resistances of the first resistors 141-148 are greater than the resistance of the second resistor 149. In a practical example, the resistance of the second resistor 149 can be 300 ohms, and the resistance of the first resistors 141 148 is substantially doubled. For example, the resistance values of the first resistors 141 to 148 may be 1.27 kilo ohms, 2.49 kilo ohms, 4.99 kilo ohms, 10 kilo ohms, 20 kilo ohms, 40.2 kilo ohms, 80.6 kilo ohms, and 162 kilo ohms, respectively. The foregoing resistance values are for illustrative purposes only, and the invention is not limited thereto. In one embodiment, the resistance values of the first resistors 141-148 are substantially in the range of 1.27 kilo ohms to 162 kilo ohms.

A practical example is given to illustrate how the voltage monitoring circuit 1 determines the voltage value of the measured voltage. Referring to Table 1, Table 1 is a voltage monitoring chart according to an embodiment of the present invention. Assuming that the voltage to be detected by the voltage monitoring circuit 1 is the first measured voltage V1, the controller 12 sends a control command CNT to the first multiplexer 10 through the control terminal C1 to turn on the input terminal I101 and Current path at output R1. At this time, the first multiplexer 10 outputs the first measured voltage V1 to the first input terminal I161 of the first comparison circuit 16 through the output terminal R1. On the other hand, the component 121 of the controller 12 outputs a plurality of potentials P1 to P8, wherein the potentials P1 to P8 are sequentially switched in accordance with the switching instruction of the controller 12. More specifically, each time the potentials P1 to P8 are switched, a first reference voltage is generated correspondingly. The voltage monitoring circuit 1 compares the first measured voltage V1 with the generated first reference voltage to generate a first comparison result. For example, as shown in Table 1, the initial state of the potentials P1 P P8 outputted by the component 121 is 00000000, which correspondingly generates the first reference voltage VR_1 and outputs to the second input terminal I162 of the first comparison circuit 16. The first reference voltage VR_1 and the first measured voltage V1 are compared by the first comparison circuit 16, thereby generating a first comparison result L1, and the first comparison result L1 is transmitted to the controller 12 through the output terminal R163. Then, the potentials P1 to P8 are switched to 00000001 according to the switching instruction of the controller 12, which correspondingly generates the first reference voltage VR_2 and outputs to the second input terminal I162 of the first comparison circuit 16. The first reference voltage VR_2 and the first measured voltage V1 are compared by the first comparison circuit 16, thereby generating a first comparison result L2, and the first comparison result L2 is transmitted to the controller 12 through the output terminal R163. By analogy, the controller 12 receives the plurality of first comparison results L1 L L256, and determines the voltage value of the first measured voltage V1 according to the first comparison results L1 L L256. Table I

In an embodiment, if the potential information of the two adjacent first comparison results are different, the controller 12 determines that the voltage value of the first measured voltage is between the adjacent two first comparison results. Between the voltage values of the two first reference voltages respectively corresponding to each other. In the example of the foregoing Table 1, it is assumed that the potential information of the first comparison result L1~L4 is kept at a low potential, and when the first comparison result L5 starts to be converted to a high potential, the first measured voltage V1 is also indicated. The voltage value is between the first reference voltage VR_4 and the voltage value of the first reference voltage VR_5. Thereby, the voltage monitoring circuit 1 can estimate the voltage value of the first measured voltage V1. In actual operation, after the controller 12 of the voltage monitoring circuit 1 completes the determination of the voltage value of the first measured voltage V1, the controller 12 can turn on another current path in the first multiplexer 10 to output another a first signal to be measured, and using the above detection method to determine the voltage value of the other first measured voltage. In other words, the voltage monitoring circuit 1 of the present invention utilizes the multi-switching architecture of the first multiplexer 10, and the multi-potential switching causes the resistor network circuit 14 to sequentially output a plurality of reference voltages for comparison with the measured voltage. To achieve monitoring of multiple channel voltages in the server. In this way, the input/output ports of the controller (such as the CPLD) can be reduced, and the stability of the circuit operation during the monitoring voltage can be improved.

Please refer to FIG. 3. FIG. 3 is a circuit diagram of a voltage monitoring circuit according to another embodiment of the present invention. The voltage monitoring circuit 2 of FIG. 3 includes a first multiplexer 20, a first comparison circuit 26, a second multiplexer 28, a second comparison circuit 30, a controller 22, and a resistor network circuit 24. The first multiplexer 20 has a plurality of input terminals I201 to I208, an output terminal R2, and a control terminal C2. Each input end of the first multiplexer 20 receives a corresponding one of the plurality of second measured voltages V1 V V8. Similarly, the second multiplexer 28 has a plurality of input terminals I281 to I288, an output terminal R3 and a control terminal C3. Each input of the second multiplexer 28 receives a corresponding one of the plurality of second measured voltages V9-V16. The controller 22 is electrically connected to the control terminal C2 of the first multiplexer 20 and the control terminal C3 of the second multiplexer 28, respectively. The controller 22 is configured to control, by the control terminal C2 of the first multiplexer 20, the first multiplexer 20 to output one of the second measured voltages V1 V V8 at the output end R2, and to pass the second multiplex The control terminal C3 of the controller 28 controls the second multiplexer 28 to output one of the second measured voltages V9-V16 at the output terminal R3. The component 221 inside the controller 22 can provide a detection signal VT comprising a plurality of potentials P1~P8. The resistor network circuit 24 can sequentially generate a plurality of first reference voltages and a plurality of second reference voltages according to the switching of the potentials P1 to P8. Similar to the embodiment of FIG. 2, the first comparison circuit 26 has a comparator 261, a resistor 263 and a capacitor 265, and the second comparison circuit 30 has a comparator 301, a resistor 303 and a capacitor 305. The resistor network circuit 24 includes a plurality of first resistors 241 248, 248, 251, and an operator 240.

The first comparison circuit 26 has a first input terminal I261, a second input terminal I262 and an output terminal R263. The first input terminal I261 of the first comparison circuit 26 is electrically connected to the output terminal R2 of the first multiplexer 20, and the second input terminal I262 of the first comparison circuit 26 is electrically connected to the resistor network circuit 24. The first comparison circuit 26 is configured to sequentially compare the generated first reference voltages with the outputted first measured voltages, to sequentially generate a plurality of second comparison results, and sequentially perform the second The comparison result is transmitted to the controller 22 through the output terminal R263 of the first comparison circuit 26, whereby the voltage value of the first measured voltage is determined.

The second comparison circuit 30 has a first input terminal I301, a second input terminal I302 and an output terminal R303. The first input terminal I301 of the second comparison circuit 30 is electrically connected to the output terminal R3 of the second multiplexer 28, and the second input terminal I302 of the second comparison circuit 30 is electrically connected to the resistor network circuit 24, and the second comparison circuit 30 is used. Comparing the generated second reference voltages with the outputted second measured voltages in sequence, respectively, sequentially generating a plurality of second comparison results and sequentially passing the second comparison results through the second comparison The output R303 of the circuit 30 is passed to the controller 22 for determining the voltage value of the second measured voltage. The manner in which the voltage monitoring circuit 2 of FIG. 3 determines the voltage values of the first measured voltage and the second measured voltage is similar to the embodiment of FIG. 2, and thus will not be described again. Since the wiring architecture inside some servers is quite complex, the relative voltage of more channels needs to be detected. Through the voltage monitoring circuit 1 and the voltage monitoring circuit 2 proposed by the present invention, it is possible to detect the channel voltage of 8 channels and the channel voltage of 16 channels, respectively. Those skilled in the art can further extend the circuit architecture of the aforementioned voltage monitoring circuit to the detection of 32 channel voltages. This reduces the input/output ports of the controller (such as the CPLD) that are required to detect the voltage, and also improves the stability of the circuit during the detection of the voltage.

Please refer to FIG. 4. FIG. 4 is a flowchart of a method for monitoring a voltage according to an embodiment of the present invention, which is applicable to the voltage monitoring circuit of FIG. As shown in FIG. 2 and FIG. 4, in step S401, the voltage monitoring circuit 1 controls the first multiplexer 10 to output one of the plurality of first measured voltages V1 to V8 according to the control command CNT from the controller 12. . In step S403, the voltage monitoring circuit 1 switches the plurality of potentials P1 to P8 included in the detection signal VT generated by the controller 12 according to the switching instruction from the controller 12, and repeatedly executes the comparison program in sequence, thereby further A plurality of first comparison results are generated. In step S405, the voltage monitoring circuit 1 determines the voltage value of the output first measured voltage according to the comparison results. The comparison procedure described above comprises the following two steps. Step 1: When the potentials are switched for the ith time, a reference voltage is generated according to the potentials of the ith switching, k is an integer greater than 3, and i is an integer less than k and greater than or equal to 0. Step 2: Compare the reference voltage with the measured voltage to be measured. The switching of the potentials P1 to P8 includes switching at least one of the potentials P1 to P8 from a high potential to a low potential or from a low potential to a high potential.

Specifically, as shown in the foregoing Table 1, the initial states of the potentials P1 to P8 are 00000000, which correspondingly generate the first reference voltage VR_1. The first reference voltage VR_1 and the first measured voltage V1 are compared by the first comparison circuit 16, thereby generating a first comparison result L1, and transmitting the first comparison result L1 to the controller 12. Then, the potentials P1 P P8 are converted into 00000001 according to the switching instruction of the controller 12 for the first time, which correspondingly generates the first reference voltage VR_2. The first reference voltage VR_2 and the first measured voltage V1 are compared by the first comparison circuit 16, thereby generating a first comparison result L2, and transmitting the first comparison result L2 to the controller 12. Then, the potentials P1 P P8 are switched to 00000010 according to the switching instruction of the controller 12, which correspondingly generates the first reference voltage VR_3. The first reference voltage VR_3 and the first measured voltage V1 are compared by the first comparison circuit 16, thereby generating a first comparison result L3, and transmitting the first comparison result L3 to the controller 12, and so on.

In other words, the first reference voltage corresponding to each potential switching is compared with the output first measured voltage through the first comparison circuit 16, respectively, to generate a plurality of comparison results. In this embodiment, the first comparison circuit 16 outputs 256 comparison results to the controller 12. The controller 12 determines the voltage value of the output first measured voltage according to the first comparison results. Since the embodiment of the present invention is based on the octet potentials P1 to P8, the total number of potential switching times is 255 (sequentially switched from 00000000 to 11111111). However, the invention is not limited to an octet potential.

Please refer to FIG. 5. FIG. 5 is a flowchart of a method for monitoring a voltage according to another embodiment of the present invention. As shown in FIG. 5, step S501 and step S503 are similar to step S401 and step S403, except that in step S505, the controller determines, according to the comparison results, that the voltage value of the measured voltage further includes steps S505a to S505c. In step S505a, the controller determines whether the potential information of the adjacent first comparison result and the second comparison result among the comparison results are different. When the potential information of the first comparison result and the second comparison result are different, in step S505b, the controller determines that the voltage value of the measured voltage is corresponding to the first comparison result and the second comparison result respectively. Between the voltage values of the two reference voltages. On the other hand, when the potential information of the first comparison result and the second comparison result are the same, in step S505c, the controller further determines whether the potential information of the second comparison result and the third comparison result are different, wherein the third The comparison result is adjacent to the second comparison result. In the foregoing Table 1, the controller sequentially determines the potential states of the comparison results. When the adjacent comparison results are the same, for example, the first comparison result L3 and L4 are both low, the potential state of the next comparison result and the previous comparison result is further judged. When the potential states of the two are different, for example, the first comparison results L4 and L5 are low potential and high potential, respectively, it can be determined that the voltage value of the measured voltage is between the first reference voltages VR_4 and VR_5.

In summary, in the voltage monitoring circuit and the voltage monitoring method proposed by the present invention, the multi-switching architecture of the multiplexer is combined with the combination of the resistor weight network and the voltage comparison circuit to enable multiple potential switching. The generated plurality of reference voltages can be compared with the measured voltage through the voltage comparison circuit, so that the controller of the voltage monitoring circuit can sequentially measure the voltage values of the plurality of channels in the server, thereby realizing the voltage of each channel of the server. Measure the stability of the process and reduce the resources that occupy the controller's output/input ports.

Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

1, 2‧‧‧ voltage monitoring circuit

10, 20‧‧‧ first multiplexer

12, 22‧‧‧ controller

14, 24‧‧‧Resistor network circuit

16, 26‧‧‧ First comparison circuit

121, 221‧‧‧ parts

140, 240‧‧‧ arithmetic

141~148, 241~248‧‧‧ first resistance

149, 251‧‧‧second resistance

16, 26‧‧‧ First comparison circuit

161, 261, 301‧ ‧ comparator

263, 303‧‧‧ resistance

265, 305‧‧‧ capacitor

28‧‧‧Second multiplexer

30‧‧‧Second comparison circuit

I101~I108, I201~I208, I281~I288‧‧‧ input

R1, R2, R3‧‧‧ output

C1, C2, C3‧‧‧ control end

V1~V8‧‧‧ first measured voltage

V9~V16‧‧‧Second measured voltage

P1~P8‧‧‧ potential

I141, T1‧‧‧ first end

I142, T2‧‧‧ second end

R143‧‧‧ third end

I161, I261, I301‧‧‧ first input

I162, I262, I302‧‧‧ second input

R163, R263, R303‧‧‧ output

CNT‧‧‧ control instructions

VT‧‧‧ detection signal

FIG. 1 is a circuit diagram of a voltage monitoring circuit according to an embodiment of the invention. 2 is a detailed circuit diagram of a voltage monitoring circuit according to the embodiment of FIG. 1 of the present invention. FIG. 3 is a circuit diagram of a voltage monitoring circuit according to another embodiment of the present invention. 4 is a flow chart of a method of voltage monitoring method according to an embodiment of the invention. FIG. 5 is a flow chart of a method for monitoring a voltage according to another embodiment of the present invention.

Claims (9)

A voltage monitoring circuit includes: a first multiplexer having a plurality of input terminals, an output terminal and a control terminal, each of the input terminals of the first multiplexer receiving a plurality of first measured voltages Corresponding one; a controller electrically connected to the control end of the first multiplexer, the controller controlling the first multiplexer to the first multiplexer through the control end of the first multiplexer The output terminal outputs one of the first measured voltages, and the controller generates a detection signal, the detection signal includes a plurality of potentials, and the controller has a component for outputting a switching instruction according to the controller And the resistor network circuit includes a plurality of first resistors, and one end of the first resistors is connected to the controller for respectively receiving the potentials of the detection signals, and the resistor network circuit is used for And generating, according to the switching of the potentials, a plurality of first reference voltages; and a first comparison circuit having a first input end, a second input end, and an output end, the first of the first comparison circuit Input electrical Connected to the output end of the first multiplexer, the second input end of the first comparison circuit is electrically connected to the resistor network circuit, and the first comparison circuit is configured to respectively sequentially connect the first reference voltages Comparing the outputted first measured voltages to sequentially generate a plurality of first comparison results and sequentially transmitting the first comparison results to the controller through the output end of the first comparison circuit, according to Determining a voltage value of the first measured voltage, wherein each of the first comparison results has potential information. The voltage monitoring circuit of claim 1, wherein if the potential information of the two adjacent first comparison results are different, the controller determines that the voltage value of the first measured voltage is between the adjacent two The first comparison result corresponds between the voltage values of the two first reference voltages. The voltage monitoring circuit of claim 1, wherein the switching of the potentials comprises at least one of the potentials being switched from a high level to a low level or from a low level to a high level. The voltage monitoring circuit of claim 1, wherein the resistor network circuit further comprises: a second resistor having a first end and a second end; and an operator having a first end and a second end The first end of the computing device is electrically connected to the other end of the first resistor, and the second end of the computing device is electrically connected to the first end of the second resistor and the operator The first reference voltage is output by the second end of the second resistor, and the resistance of the first resistors is greater than the resistance of the second resistor. The voltage monitoring circuit of claim 1, wherein the first resistors are k resistors, and the resistance of the (i+1)th first resistor is substantially the resistance of the ith first resistor. Twice, k is an integer greater than 1, and i is an integer greater than 0 and less than k. The voltage monitoring circuit of claim 1, wherein the resistance values of the first resistors are substantially in the range of 1.27 kilo ohms to 162 kilo ohms. The voltage monitoring circuit of claim 1, further comprising: a second multiplexer having a plurality of inputs, an output, and a control, each of the inputs of the second multiplexer receiving Corresponding one of the second measured voltages, the controller is electrically connected to the control end of the second multiplexer, and the controller is configured to control the second multiplexer through the control end of the second multiplexer Outputting, at the output end of the second multiplexer, one of the second measured voltages, wherein the resistor network circuit further generates a plurality of second reference voltages according to the switching of the potentials; and a second a comparison circuit having a first input end, a second input end and an output end, the first input end of the second comparison circuit being electrically connected to the output end of the second multiplexer, the second comparison circuit The second input end is electrically connected to the resistor network circuit, and the second comparison circuit is configured to sequentially compare the generated second reference voltages with the outputted second measured voltages to sequentially correspond Generating a plurality of second comparison results and sequentially ordering the second The comparison result is transmitted to the controller through the output end of the second comparison circuit to determine the voltage value of the second measured voltage. A voltage monitoring method is suitable for a voltage monitoring circuit, the voltage monitoring method includes: controlling a multiplexer to output one of a plurality of measured voltages according to a control command from a controller; Switching instructions, so that a plurality of potentials included in a detection signal generated by the controller are switched, and a comparison program is repeatedly executed in sequence to generate a plurality of comparison results, and the number of repeated executions is k times; The comparison result determines the voltage value of the measured voltage; wherein the comparison program includes: when the potentials are switched for the ith, generating a reference voltage according to the potentials of the ith switching, k is an integer greater than 3. And i is an integer less than k and greater than or equal to 0; and comparing the reference voltage with the measured voltage; wherein the switching of the potentials includes at least one of the potentials being switched from a high level to a low level or by The low level switches to a high level. The voltage monitoring method of claim 8, wherein determining the voltage value of the measured voltage according to the comparison results comprises: determining potential information of a first comparison result and a second comparison result of the comparison results Whether the difference is different when the potential information of the first comparison result and the second comparison result are different, the controller determines that the voltage value of the measured voltage is between the first comparison result and the second comparison result Between the voltage values of the two corresponding reference voltages; and when the potential information of the first comparison result and the second comparison result are the same, determining the potential of the second comparison result and a third comparison result Whether the information is different, wherein the third comparison result is adjacent to the second comparison result.