CN111426866A - Voltage monitoring system and method thereof - Google Patents

Voltage monitoring system and method thereof Download PDF

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Publication number
CN111426866A
CN111426866A CN201911392637.9A CN201911392637A CN111426866A CN 111426866 A CN111426866 A CN 111426866A CN 201911392637 A CN201911392637 A CN 201911392637A CN 111426866 A CN111426866 A CN 111426866A
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voltage
signal
reset
clock signal
circuit
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CN111426866B (en
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涂结盛
蔡德宗
王路茜
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Nuvoton Technology Corp
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Nuvoton Technology Corp
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/0084Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring voltage only
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/22Modifications for ensuring a predetermined initial state when the supply voltage has been applied

Abstract

The invention provides a voltage monitoring system and a method thereof, which are used for monitoring a power supply voltage provided for a functional circuit, the voltage monitoring system comprises a clock signal generating circuit, a reference voltage generating circuit and a low voltage resetting module, wherein the clock signal generating circuit generates a clock signal, the reference voltage generating circuit generates a reference voltage and updates the reference voltage according to the clock signal, in a normal mode, the low voltage resetting module continuously executes a voltage detection function for detecting whether the power supply voltage is lower than a first voltage threshold value, and when the power supply voltage is lower than the first voltage threshold value, the low voltage resetting module outputs a resetting signal to reset the functional circuit; in the power saving mode, the low voltage reset module periodically and discontinuously executes a voltage detection function according to the clock signal.

Description

Voltage monitoring system and method thereof
Technical Field
The present invention relates to a voltage monitoring system, and more particularly, to a voltage monitoring system with low power consumption and low voltage reset detection function and a method thereof.
Background
In order to prolong the service life of most battery-powered devices, a Power-saving mode (also called a Power-down mode) is generally entered when a functional circuit (functional circuit) is not operating, so as to reduce Power consumption.
In addition, since the battery-powered power supply voltage decreases with time, in order to avoid the functional circuit from being damaged due to the excessively low power supply voltage drop, a low-voltage reset (L VR) circuit is provided to monitor whether the power supply voltage is lower than a voltage threshold, and if so, the low-voltage reset circuit outputs a reset signal to reset the functional circuit, thereby protecting the functional circuit.
However, in the power saving mode, the power consumption of the low voltage reset circuit needs to be further reduced to more effectively prolong the service time of the battery.
Disclosure of Invention
The present invention is directed to a voltage monitoring system with low power consumption and suitable for power saving mode, so as to solve the above-mentioned problems.
To achieve the above objective, the present invention provides a voltage monitoring system for monitoring a power supply voltage provided to a functional circuit. The voltage monitoring system comprises a clock signal (clock signal) generating circuit, a reference voltage generating circuit and a low voltage reset module. The clock signal generating circuit is used for generating a clock signal. The reference voltage generating circuit is used for generating a reference voltage and updating the reference voltage according to the clock signal. In a first mode, the low voltage reset module continuously performs a voltage detection function for detecting whether the power voltage is lower than a first voltage threshold, and when the power voltage is lower than the first voltage threshold, the low voltage reset module outputs a reset signal to reset the functional circuit; in a second mode, the low voltage reset module periodically and discontinuously executes the voltage detection function according to the clock signal. The first voltage threshold corresponds to the reference voltage.
In one embodiment, the low voltage reset module includes a low voltage reset circuit for performing a voltage detection function and a power consumption control unit for periodically turning on or off the low voltage reset circuit according to a clock signal in the second mode.
In one embodiment, the power consumption control unit includes a first determining unit that generates an enable signal of the low voltage reset circuit according to the clock signal and an enable condition.
In one embodiment, the power consumption control unit includes a second determining unit that generates a mask signal for masking the output signal of the low voltage reset circuit according to the clock signal and a mask condition.
In one embodiment, in the second mode, the low voltage reset module periodically and discontinuously performs the voltage detecting function according to a first frequency when the power voltage is lower than a second voltage threshold, and periodically and discontinuously performs the voltage detecting function according to a second frequency when the power voltage is higher than the second voltage threshold, wherein the second frequency is lower than the first frequency.
In one embodiment, the clock signal generating circuit includes an oscillator outputting an oscillation signal and a counter counting according to the oscillation signal and periodically generating an update signal to the reference voltage generating circuit according to a predetermined count.
In one embodiment, the clock signal generating circuit includes an oscillator and a counter, the oscillator outputs an oscillation signal, the counter performs counting according to the oscillation signal, and the power consumption control unit includes a first determining unit that controls the low voltage reset circuit to be in an on state or an off state according to an on condition and a count value output by the counter.
In one embodiment, the first mode is a normal mode, and the second mode is a power saving mode.
To achieve the above objectives, the present invention provides a voltage monitoring method for monitoring a power supply voltage provided to a functional circuit. The voltage monitoring method comprises providing a clock signal generating circuit to generate a clock signal; providing a reference voltage generating circuit to generate a reference voltage, wherein the reference voltage generating circuit updates the reference voltage according to the clock signal; providing a low voltage reset module to perform a voltage detection function for detecting whether the power voltage is lower than a first voltage threshold, wherein the low voltage reset module outputs a reset signal to reset the functional circuit when the power voltage is lower than the first voltage threshold, and the first voltage threshold corresponds to the reference voltage; in a first mode, the low voltage reset module is used for continuously executing the voltage detection function; in a second mode, the low voltage reset module is used for periodically and discontinuously executing the voltage detection function according to the clock signal.
In one embodiment, the voltage monitoring method further comprises generating a mask signal for masking the output signal of the low voltage reset module according to the clock signal and a mask condition.
Drawings
FIG. 1 is a block diagram of a voltage monitoring system according to the present invention;
FIG. 2 is a block diagram illustrating an embodiment of a voltage monitoring system according to the present invention;
FIG. 3 is a block diagram illustrating a power consumption control unit of the voltage monitoring system according to an embodiment of the present invention;
FIG. 4 is a timing diagram of operation signals of an embodiment of a power consumption control unit of the voltage monitoring system of the present invention;
FIG. 5 is a timing diagram of operation signals of an embodiment of the voltage monitoring system of the present invention;
FIG. 6 is a timing diagram of the operation signals of another embodiment of the voltage monitoring system of the present invention;
FIG. 7 is a flow chart of a voltage monitoring method of the present invention;
FIG. 8 is a flowchart of a voltage monitoring method according to an embodiment of the present invention.
[ description of symbols ]
10 voltage stabilizing circuit
101 operating voltage
11: linear low dropout circuit
20 low voltage reset module
Reset signal 201
21 low voltage reset circuit
211. TH1 first Voltage threshold
212 output signal
22 power consumption control unit
221. 231 start signal
23. 23a first judging unit
24. 24a second judging unit
241 mask signal
25 selection unit
26 OR gate
Reference voltage generating circuit
301. 311 reference voltage
31 bandgap circuit
40 clock signal generating circuit
401 clock signal
41: oscillator
411 oscillating signal
42 counter
421 count value
422 update signal
50 functional circuit
VDD power supply voltage
TH2 second Voltage threshold
T0-T8 period
P0-P5 time points
EN starting signal input end
Detailed Description
The following detailed description of the embodiments of the present invention will be provided in conjunction with the drawings and examples, so that how to implement the technical means for solving the technical problems and achieving the technical effects of the present invention can be fully understood and implemented.
Referring to fig. 1, a block diagram of a voltage monitoring system according to the present invention is shown in fig. 1. the voltage monitoring system according to the present invention is suitable for a power supply system, which includes a voltage regulator circuit 10, an input terminal of the voltage regulator circuit 10 is electrically connected to a power supply terminal, the voltage regulator circuit 10 can convert a power supply voltage VDD at the power supply terminal into an operating voltage 101 required by a functional circuit 50, and in one embodiment, the voltage regulator circuit 10 can be a linear low dropout (L DO) circuit.
In practical applications, the power system is usually disposed on a mobile device, and a battery is used as a power source, so that the voltage of the battery gradually decreases after a long time of use. When the power supply voltage VDD is lower than a voltage threshold, the functional circuit 50 of the mobile device may be damaged or not function properly. Therefore, the voltage monitoring system of the present invention can monitor the power supply voltage VDD and has lower power consumption.
As shown in fig. 1, the voltage monitoring system includes a clock signal generating circuit 40, a reference voltage generating circuit 30, and a low voltage reset module 20. Clock signal generation circuitry 40 may generate clock signal 401. The reference voltage generating circuit 30 may generate the reference voltage 301 and update the reference voltage 301 according to the clock signal 401. In one embodiment, the reference voltage generating circuit 30 may be a Bandgap (Bandgap) circuit; the clock signal generating circuit 40 may include an oscillator 41 and a counter 42. The low voltage reset module 20 and the reference voltage generating circuit 30 share the clock signal 401 of the clock signal generating circuit 40, which can synchronize the Bandgap refresh (Bandgap refresh) time of the low voltage reset module 20 and the reference voltage generating circuit 30 and also save the gate count (gate count).
The low voltage reset module 20 may perform a voltage detection function to detect whether the power voltage VDD is lower than the first voltage threshold 211, and when the low voltage reset module 20 determines that the power voltage VDD is lower than the first voltage threshold 211, the low voltage reset module 20 outputs a reset (reset) signal 201 to reset the functional circuit 50, thereby preventing the functional circuit 50 from being damaged or malfunctioning. The mobile device usually has a normal mode and a power saving mode, in the normal mode, in order to ensure the normal function, the functional circuit 50 operates normally and consumes higher power; in the power saving mode, the functional circuit 50 is turned off or sleep to reduce power consumption for a long time.
In one embodiment, the low voltage reset module 20 may include a low voltage reset circuit 21 and a power consumption control unit 22, the low voltage reset circuit 21 is configured to perform the voltage detection function, and the power consumption control unit 22 may periodically turn on or off the low voltage reset circuit 21 according to the clock signal 401 in the power saving mode.
Since the power consumption of the low voltage reset module 20 is much lower than that of the functional circuit 50, in the normal mode, the low voltage reset module 20 can continuously perform the voltage detection function to immediately detect whether the power system has a sudden voltage drop. In the power saving mode, in order to further reduce the power consumption of the low voltage reset module 20, the low voltage reset module 20 may periodically and discontinuously perform the voltage detection function according to the clock signal 401; in other words, the voltage detection function is intermittently performed, and when the voltage detection function is not performed, the power consumption of the low-voltage reset module 20 is very low, thereby effectively reducing the power consumption of the low-voltage reset module 20 in the power saving mode.
It should be noted that the first voltage threshold 211 corresponds to the reference voltage 301, that is, the first voltage threshold 211 can be obtained from the reference voltage 301, for example, the low voltage reset module 20 can include a voltage dividing circuit for dividing the reference voltage 301 to obtain the first voltage threshold 211, the first voltage threshold 211 can be, for example, 1.5V, the first voltage threshold 211 of 1.5V is merely an example, and the first voltage threshold 211 can be other values without being limited to the recited range of the present invention; in another embodiment, the low voltage reset module 20 may use a plurality of voltage thresholds, and a plurality of voltage dividing circuits may divide the reference voltage 301 to obtain different voltage thresholds. Techniques for this are well known to those skilled in the art and will not be described in detail herein.
Please refer to fig. 5, which is a timing diagram illustrating operation signals of the voltage monitoring system according to an embodiment of the present invention. In the figure, before the time point P0, the voltage monitoring system is in the normal mode, so the voltage detection function is continuously performed; after the time point P0, the voltage monitoring system enters the power saving mode, the voltage detection function is performed intermittently, i.e., the voltage monitoring system performs the voltage detection function only during the periods T0, T1, T2, T3, and T4, and turns off the voltage detection function during other periods, thereby effectively reducing power consumption. As shown in fig. 5, when the voltage monitoring system performs the voltage detection function during the period T4, it is detected that the power voltage VDD is lower than the first voltage threshold TH1, and the low voltage reset module 20 sends the reset signal 201 to the functional circuit 50.
Fig. 2 to 4 are block schematic diagrams of a voltage monitoring system according to an embodiment of the present invention, a power consumption control unit according to an embodiment of the present invention, and a timing diagram of operation signals. In this embodiment, the voltage monitoring system includes a low voltage reset circuit 21, a first determining unit 23, a second determining unit 24, a selecting unit 25, a Bandgap (Bandgap) circuit 31, an oscillator 41 and a counter 42. The low voltage reset circuit 21 is used to perform the voltage detection function, and the bandgap circuit 31 can output a reference voltage 311 to the low voltage reset circuit 21.
The oscillator 41 is configured to output an oscillation signal 411, which is a periodic signal. The counter 42 counts according to the oscillating signal 411 and periodically generates an update signal 422 to the reference voltage generating circuit 30 according to a predetermined counting amount (preset). For example, the predesigned number may be 1000, the counter 42 may count 1000 times and then return to zero, and output the update signal 422; thus, the period (period) of the refresh signal 422 is 1000 times that of the oscillation signal 411, and the frequency of the oscillation signal 411 is 1000 times that of the refresh signal 422, and the counter 42 can be a frequency divider or a frequency down converter. The above "1000 times" is merely an example and not a limitation of the present invention; in practical applications, the user can set the multiple relationship between the frequencies of the update signal 422 and the oscillation signal 411 by himself.
The first determining unit 23 generates an enable signal 231 of the low voltage reset circuit 21 according to the clock signal 401 and an enable condition. Since the low voltage reset circuit 21 performs the voltage detection function intermittently and periodically in the power saving mode, in an embodiment, the start condition may be that when the count value is in a specific range, the first determining unit 23 generates the start signal 231 to the start signal input end EN of the low voltage reset circuit 21, and the low voltage reset circuit 21 is started to perform the voltage detection function to determine whether the reset signal is generated; at the count value outside the specific range, the first determining unit 23 does not generate the start signal 231, so the low voltage reset circuit 21 does not perform the voltage detecting function, thereby achieving the effect of saving power consumption.
In one embodiment, the start condition may be set to "count value is less than or equal to 2", so when the count value is 0, the first determining unit 23 generates the start signal 231 to the start signal input EN of the low voltage reset circuit 21 to start the low voltage reset circuit 21 to perform the voltage detecting function, when the count values are 0, 1, and 2, the start signal 231 is at high level, so that the low voltage reset circuit 21 starts to perform the voltage detecting function, and at other count values, the start signal 231 is at low level, so that the low voltage reset circuit 21 is not started and consumes no energy. Therefore, the effect of reducing power consumption by periodically turning on and off the low voltage reset circuit 21 can be achieved.
The low voltage reset circuit 21 performs the voltage detection function to protect the functional circuit 50, so the output signal of the low voltage reset circuit 21 has to have high accuracy, but the low voltage reset circuit 21 is frequently turned on and off periodically in the power-saving mode, and the low voltage reset circuit 21 requires a standby time when it is just turned on, and the output signal of the low voltage reset circuit 21 is meaningless during the standby time and cannot be provided to the functional circuit 50. Therefore, in an embodiment, the second determining unit 24 may generate a masking signal 241 for masking the output signal 212 of the low voltage reset circuit 21 according to the clock signal 401 and a masking condition. The masking condition corresponds to the period when the low voltage reset circuit 21 is just turned on, so as to prevent the functional circuit 50 from malfunction due to the transmission of an meaningless signal to the functional circuit 50.
The selection unit 25 receives the mask signal 241 and the output signal 212 of the low voltage reset circuit 21, and when the selection unit 25 receives the mask signal 241 or the mask signal 241 is in an enabled state (enabled state), the selection unit does not output the output signal 212 of the low voltage reset circuit 21; on the contrary, when the selection unit 25 does not receive the mask signal 241 or the mask signal 241 is in the disabled state, the output signal 212 of the low voltage reset circuit 21 is output. In one embodiment, the masking condition may be "count value equal to 0", so that when the count value 421 is 0, the masking signal 241 is at high level, which is an enabled state, so that the selection unit 25 does not output the output signal 212 of the low voltage reset circuit 21, as shown in fig. 4.
Therefore, in an embodiment, when the preset count of the counter 42 is set to 1000 and the start condition is set to "count value is less than or equal to 2", in the power saving mode, when the count values are 0, 1, and 2, the first determining unit 23 generates the high-level start signal 231 to the start signal input terminal EN of the low-voltage reset circuit 21 to start the low-voltage reset circuit 21 to perform the voltage detection function, and when the count values are 3 to 999, the first determining unit 23 generates the high-level start signal 231, the low-voltage reset circuit 21 does not perform the voltage detection function, then the count value returns to zero, and the above operations are repeated, thereby monitoring the state of the power supply voltage and reducing power consumption. In addition, in another embodiment, the voltage monitoring system can add the second determination unit 24 and set the mask condition to "count value equal to 0", so when the count value is 0, the selection unit 25 does not output the output signal of the low voltage reset circuit 21, so as to avoid malfunction of the functional circuit 50.
Fig. 3 is a block diagram of an embodiment of a power consumption control unit according to the present invention, which is implemented by the selection unit 25 or the gate 26, and the enable state of the reset signal 201 is a low level L, such as a ground voltage, the enable condition of the first determination unit 23a is "count value less than or equal to 2", and the mask condition of the second determination unit 24a is "count value equal to 0", so that when the count value 421 is 0, the first determination unit 23a outputs a high level signal H, the low voltage reset circuit 21 is enabled, and the second determination unit 24a also outputs a high level signal H, so that no matter whether the output signal of the low voltage reset circuit 21 is H or L or the reset signal 201 of the gate 26 is H, which is the disable state of the reset signal 201, and thus the functional circuit 50 is not reset, thereby achieving an effect of blocking signals generated when the low voltage reset circuit 21 is just enabled.
When the count value 421 is 1, the first determining unit 23a outputs the high level signal H, and the second determining unit 24a outputs the low level signal L, so that the reset signal 201 of the or gate 26 corresponds to the output signal 212 of the low voltage reset circuit 21. when the low voltage reset circuit 21 detects that the power voltage is lower than the voltage threshold, the low voltage reset circuit 21 outputs the low level signal L, so that the reset signal 201 of the or gate 26 is the low level signal L, which is the enabled state of the reset signal 201, and therefore the functional circuit 50 is reset, otherwise, when the low voltage reset circuit 21 detects that the power voltage is higher than the voltage threshold, the low voltage reset circuit 21 outputs the high level signal H, and the functional circuit 50 is not reset.
Please refer to fig. 6, which is a timing diagram illustrating operation signals of a voltage monitoring system according to another embodiment of the present invention. This embodiment is different from the previous embodiments in that the embodiment uses two voltage thresholds and turns on or off the low voltage reset circuit 21 at different frequencies in different stages. As shown in fig. 6, the voltage monitoring system of this embodiment uses a first voltage threshold TH1 and a second voltage threshold TH2, the second voltage threshold TH2 is higher than the first voltage threshold TH 1. In the power saving mode (i.e., after the time point P3), when the power voltage VDD is higher than the second voltage threshold TH2 (i.e., between the time point P3 and the time point P4), the low-voltage reset module 20 may periodically and discontinuously perform the voltage detection function according to a second frequency; when the power voltage VDD is lower than the second voltage threshold TH2 (i.e., after the time point P4), the low voltage reset module 20 may periodically and discontinuously perform the voltage detection function according to a first frequency, and the second frequency is lower than the first frequency.
As shown in fig. 6, between the time point P3 and the time point P4, the voltage detection function is performed during the periods T0, T1, and T2, and is not performed during the other periods; and after the time point P4, the voltage detection function is performed during the periods T3, T4, T5, T6, T7, T8, and it may be detected during the period T8 that the power supply voltage is lower than the first voltage threshold TH 1. Due to the closer proximity to the first voltage threshold TH1, the voltage detection function is performed more frequently to confirm that the timing when the power voltage is detected to be lower than the first voltage threshold TH1 in time, and to issue the reset signal to protect the functional circuit.
Please refer to fig. 7, which is a flowchart illustrating a voltage monitoring method according to the present invention. The voltage monitoring method of the present invention is used for monitoring a power voltage supplied to a functional circuit, and the voltage monitoring method includes steps S71-S76. In step S71, a clock signal generating circuit is provided to generate a clock signal. In step S72, a reference voltage generating circuit is provided to generate a reference voltage, and the reference voltage generating circuit updates the reference voltage according to the clock signal. In step S73, a low voltage reset module is provided to perform a voltage detection function for detecting whether the power voltage is lower than a first voltage threshold, and when the power voltage is lower than the first voltage threshold, the low voltage reset module outputs a reset signal to reset the functional circuit, wherein the first voltage threshold 211 corresponds to the reference voltage 301.
In step S74, it is determined whether to enter the power saving mode, if yes, step S75 is executed; if not, step S76 is executed. In step S75, the low voltage reset module is used to periodically and discontinuously perform the voltage detection function according to the clock signal 401. In step S76, the voltage detection function is continuously performed using the low voltage reset module. The clock signal generating circuit, the reference voltage generating circuit, the low voltage reset module and the related operations are already described in the foregoing, and therefore are not described herein again.
Please refer to fig. 8, which is a flowchart illustrating a voltage monitoring method according to an embodiment of the present invention. The operation of the embodiment of the voltage monitoring method in the power saving mode will be described below, and the operation in the normal mode is similar to that described in fig. 7, and therefore will not be described again. As shown in FIG. 8, the embodiment of the voltage monitoring method includes steps S81-S84.
In step S81, a bandgap circuit, an oscillator and a counter are provided, the oscillator outputs an oscillation signal, the counter counts according to the oscillation signal, the bandgap circuit generates a reference voltage, and the reference voltage is updated according to the clock signal.
In step S82, a low voltage reset module is provided to perform a voltage detection function to determine whether a reset signal is outputted. In step S83, a first determining unit is provided, and a start condition of the first determining unit is set, and a start signal of the low voltage reset circuit is generated according to the count value of the counter and the start condition by using the first determining unit.
In step S84, a second determining unit is provided, and a masking condition of the second determining unit is set, and a masking signal for masking the output of the low voltage reset circuit is generated according to the count value of the counter and the masking condition by using the second determining unit. In step S85, the on state and the off state of the low voltage reset module are periodically controlled according to the on signal and the mask signal.
In one embodiment, as shown in fig. 4, the pre-designed number of the counters may be set to 1000, the start condition may be set to "count value is less than or equal to 2", and the mask condition may be set to "count value is equal to 0", in the power saving mode, when the count value is 0, 1, 2, the first determining unit generates a high level start signal to the start signal input terminal of the low voltage reset circuit, the low voltage reset circuit is started to perform the voltage detection function, and when the count value is 0, the selecting unit does not output the output signal of the low voltage reset circuit, so as to avoid malfunction of the functional circuit. When the counting value is 3-999, the first judging unit generates a high-level starting signal, the low-voltage reset circuit does not execute the voltage detection function, then the counting value returns to zero, and the operations are repeated, so that the power consumption is reduced while the state of the power supply voltage is monitored, and the problem that the malfunction of the functional circuit is caused by the unstable initial signal due to the frequent starting of the low-voltage reset circuit is avoided. It should be noted that the preset count number, the start condition and the mask condition of the counter are only examples and are not limited.
Although the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. A voltage monitoring system for monitoring a power supply voltage provided to a functional circuit, the voltage monitoring system comprising:
a clock signal generating circuit for generating a clock signal;
a reference voltage generating circuit for generating a reference voltage and updating the reference voltage according to the clock signal; and
a low voltage reset module, which continuously performs a voltage detection function to detect whether the power voltage is lower than a first voltage threshold in a first mode, outputs a reset signal to reset the functional circuit when the power voltage is lower than the first voltage threshold, and periodically and discontinuously performs the voltage detection function according to the clock signal in a second mode, wherein the first voltage threshold corresponds to the reference voltage.
2. The voltage monitoring system of claim 1, wherein the low voltage reset module comprises a low voltage reset circuit and a power consumption control unit, the low voltage reset circuit is configured to perform the voltage detection function, and the power consumption control unit is configured to periodically turn on or off the low voltage reset circuit according to the clock signal in the second mode.
3. The voltage monitoring system of claim 2, wherein the power consumption control unit comprises a first determining unit, the first determining unit generating an enable signal of the low voltage reset circuit according to the clock signal and an enable condition.
4. The voltage monitoring system of claim 3, wherein the power consumption control unit comprises a second determining unit, and the second determining unit generates a mask signal for masking the output signal of the low voltage reset circuit according to the clock signal and a mask condition.
5. The voltage monitoring system of claim 1, wherein in the second mode, the low voltage reset module periodically and discontinuously performs the voltage detection function according to a first frequency when the power voltage is below a second voltage threshold, and periodically and discontinuously performs the voltage detection function according to a second frequency when the power voltage is above a second voltage threshold, wherein the second frequency is lower than the first frequency.
6. The voltage monitoring system of claim 1, wherein the clock signal generating circuit comprises an oscillator and a counter, the oscillator outputting an oscillating signal, the counter counting according to the oscillating signal and periodically generating an update signal to the reference voltage generating circuit according to a predetermined count.
7. The voltage monitoring system of claim 2, wherein the clock signal generating circuit comprises an oscillator and a counter, the oscillator outputs an oscillating signal, the counter counts according to the oscillating signal, the power consumption control unit comprises a first determining unit, and the first determining unit controls the low voltage reset circuit to be in an on state or an off state according to an on condition and a count value output by the counter.
8. The voltage monitoring system of claim 1, wherein the first mode is a normal mode and the second mode is a power-saving mode.
9. A voltage monitoring method for monitoring a power supply voltage provided to a functional circuit, the voltage monitoring method comprising:
providing a clock signal generating circuit to generate a clock signal;
providing a reference voltage generating circuit to generate a reference voltage, wherein the reference voltage generating circuit updates the reference voltage according to the clock signal;
providing a low voltage reset module to perform a voltage detection function for detecting whether the power voltage is lower than a first voltage threshold, wherein the low voltage reset module outputs a reset signal to reset the functional circuit when the power voltage is lower than the first voltage threshold, and the first voltage threshold corresponds to the reference voltage;
in a first mode, continuously executing the voltage detection function by using the low-voltage reset module; and
in a second mode, the low voltage reset module is used for periodically and discontinuously executing the voltage detection function according to the clock signal.
10. The voltage monitoring method of claim 9, further comprising:
and generating a mask signal for masking the output signal of the low-voltage reset module according to the clock signal and a mask condition.
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Citations (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2438273Y (en) * 2000-06-12 2001-07-04 麦肯积体电路股份有限公司 Circuit for testing mains voltage across points
CN1737596A (en) * 2004-08-19 2006-02-22 鸿富锦精密工业(深圳)有限公司 Low-voltage reset Function detection circuit
CN101183002A (en) * 2007-11-20 2008-05-21 浙江大学 Method for reducing optical fibre gyroscope power consumption
CN101191823A (en) * 2006-11-24 2008-06-04 北京中电华大电子设计有限责任公司 Low power consumption electric source monitoring circuit
TW200828001A (en) * 2006-12-25 2008-07-01 Realtek Semiconductor Corp Reset circuit and the associated method
CN201142006Y (en) * 2008-01-08 2008-10-29 硕呈科技股份有限公司 Standby-mode electric power alteration awakening device
CN101453201A (en) * 2007-11-28 2009-06-10 瑞昱半导体股份有限公司 Start reset circuit and related method thereof
CN101458538A (en) * 2008-12-17 2009-06-17 炬力集成电路设计有限公司 Method for reducing standby power consumption of power supply system and the power supply system
TW200933698A (en) * 2007-09-07 2009-08-01 Nec Electronics Corp Method of fabricating semiconductor device
TW201015282A (en) * 2008-10-09 2010-04-16 Realtek Semiconductor Corp Circuit and method of adjusting system clock in low voltage detection, and low voltage reset circuit
JP2010178464A (en) * 2009-01-28 2010-08-12 Oki Data Corp Piezoelectric transformer drive system, cold cathode tube inverter, cold cathode tube drive system and image forming apparatus
TW201112599A (en) * 2009-09-21 2011-04-01 Linear Artwork Inc Minimum leading edge blanking (MLEB) generator and method of generating MLEB signal
CN202014087U (en) * 2011-03-17 2011-10-19 上海韦尔半导体股份有限公司 Lithium battery charging protection circuit for portable system
JP2012003692A (en) * 2010-06-21 2012-01-05 Renesas Electronics Corp Voltage detection system and control method thereof
CN102447385A (en) * 2010-09-30 2012-05-09 佳能株式会社 Power supply apparatus
CN102698413A (en) * 2012-05-17 2012-10-03 羽高(上海)投资管理中心(有限合伙) Low-power-consumption wireless signaling intelligent golf and method for realizing low power consumption golf
TW201303314A (en) * 2011-07-15 2013-01-16 Askey Technology Jiangsu Ltd Frequency counter
JP2013050329A (en) * 2011-08-30 2013-03-14 Seiko Epson Corp Satellite signal reception device, satellite signal receiving method, and electronic device
US20130342947A1 (en) * 2012-06-20 2013-12-26 Fuji Electric Co., Ltd. Abnormal voltage detecting device
US20140152283A1 (en) * 2012-12-04 2014-06-05 Chengdu Monolithic Power Systems Co., Ltd. Voltage detecting circuit for switching converters and the method thereof
TW201510706A (en) * 2013-09-10 2015-03-16 Himax Tech Ltd Power-on-reset circuit
CN104900068A (en) * 2015-06-04 2015-09-09 交通运输部科学研究院 Vehicle detector, method for intermittent and variable-frequency power supply, and method for reducing power consumption of wireless transceiver module
CN105429106A (en) * 2015-12-08 2016-03-23 广州金升阳科技有限公司 Output short circuit protection method of switch power supply and circuit
CN105759928A (en) * 2016-02-03 2016-07-13 浪潮(北京)电子信息产业有限公司 Power-on reset circuit applied to high-speed protocol processor chip
CN105785405A (en) * 2014-12-26 2016-07-20 深圳艾科创新微电子有限公司 Real-time clock circuit, navigation control chip, and navigation device
CN106655727A (en) * 2017-02-07 2017-05-10 苏州锴威特半导体有限公司 Device for reducing power consumption of solar bypass switching circuit, and method implemented by device
CN108614632A (en) * 2016-12-12 2018-10-02 徐州新隆全电子科技有限公司 Low power consumption method drops in SCM Based active RFID system
TWI640784B (en) * 2018-04-24 2018-11-11 新唐科技股份有限公司 Voltage detection circuit

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7660090B1 (en) * 2007-08-27 2010-02-09 National Semiconductor Corporation Apparatus and method for input voltage transient protection with a low-voltage reset circuit
CN102393785B (en) * 2011-11-28 2013-09-25 矽力杰半导体技术(杭州)有限公司 Low-offset band-gap reference voltage source
TWI458259B (en) * 2013-07-17 2014-10-21 Generalplus Technology Inc Method for power-on sequence and device with low current power source

Patent Citations (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2438273Y (en) * 2000-06-12 2001-07-04 麦肯积体电路股份有限公司 Circuit for testing mains voltage across points
CN1737596A (en) * 2004-08-19 2006-02-22 鸿富锦精密工业(深圳)有限公司 Low-voltage reset Function detection circuit
CN101191823A (en) * 2006-11-24 2008-06-04 北京中电华大电子设计有限责任公司 Low power consumption electric source monitoring circuit
TW200828001A (en) * 2006-12-25 2008-07-01 Realtek Semiconductor Corp Reset circuit and the associated method
TW200933698A (en) * 2007-09-07 2009-08-01 Nec Electronics Corp Method of fabricating semiconductor device
CN101183002A (en) * 2007-11-20 2008-05-21 浙江大学 Method for reducing optical fibre gyroscope power consumption
CN101453201A (en) * 2007-11-28 2009-06-10 瑞昱半导体股份有限公司 Start reset circuit and related method thereof
CN201142006Y (en) * 2008-01-08 2008-10-29 硕呈科技股份有限公司 Standby-mode electric power alteration awakening device
TW201015282A (en) * 2008-10-09 2010-04-16 Realtek Semiconductor Corp Circuit and method of adjusting system clock in low voltage detection, and low voltage reset circuit
CN101458538A (en) * 2008-12-17 2009-06-17 炬力集成电路设计有限公司 Method for reducing standby power consumption of power supply system and the power supply system
JP2010178464A (en) * 2009-01-28 2010-08-12 Oki Data Corp Piezoelectric transformer drive system, cold cathode tube inverter, cold cathode tube drive system and image forming apparatus
TW201112599A (en) * 2009-09-21 2011-04-01 Linear Artwork Inc Minimum leading edge blanking (MLEB) generator and method of generating MLEB signal
JP2012003692A (en) * 2010-06-21 2012-01-05 Renesas Electronics Corp Voltage detection system and control method thereof
CN102447385A (en) * 2010-09-30 2012-05-09 佳能株式会社 Power supply apparatus
CN202014087U (en) * 2011-03-17 2011-10-19 上海韦尔半导体股份有限公司 Lithium battery charging protection circuit for portable system
TW201303314A (en) * 2011-07-15 2013-01-16 Askey Technology Jiangsu Ltd Frequency counter
JP2013050329A (en) * 2011-08-30 2013-03-14 Seiko Epson Corp Satellite signal reception device, satellite signal receiving method, and electronic device
CN102698413A (en) * 2012-05-17 2012-10-03 羽高(上海)投资管理中心(有限合伙) Low-power-consumption wireless signaling intelligent golf and method for realizing low power consumption golf
US20130342947A1 (en) * 2012-06-20 2013-12-26 Fuji Electric Co., Ltd. Abnormal voltage detecting device
US20140152283A1 (en) * 2012-12-04 2014-06-05 Chengdu Monolithic Power Systems Co., Ltd. Voltage detecting circuit for switching converters and the method thereof
TW201510706A (en) * 2013-09-10 2015-03-16 Himax Tech Ltd Power-on-reset circuit
CN105785405A (en) * 2014-12-26 2016-07-20 深圳艾科创新微电子有限公司 Real-time clock circuit, navigation control chip, and navigation device
CN104900068A (en) * 2015-06-04 2015-09-09 交通运输部科学研究院 Vehicle detector, method for intermittent and variable-frequency power supply, and method for reducing power consumption of wireless transceiver module
CN105429106A (en) * 2015-12-08 2016-03-23 广州金升阳科技有限公司 Output short circuit protection method of switch power supply and circuit
CN105759928A (en) * 2016-02-03 2016-07-13 浪潮(北京)电子信息产业有限公司 Power-on reset circuit applied to high-speed protocol processor chip
CN108614632A (en) * 2016-12-12 2018-10-02 徐州新隆全电子科技有限公司 Low power consumption method drops in SCM Based active RFID system
CN106655727A (en) * 2017-02-07 2017-05-10 苏州锴威特半导体有限公司 Device for reducing power consumption of solar bypass switching circuit, and method implemented by device
TWI640784B (en) * 2018-04-24 2018-11-11 新唐科技股份有限公司 Voltage detection circuit

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
BOB JURGILEWICZ: "Low Voltage Wizardry Provides the Ultimate Power-On Reset Circuit", 《DESIGN FEATURES》 *
江博彦: "配电网电压采集装置的设计", 《科技创新导报》 *

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