JP4756301B2 - Driving method of flying capacitor type assembled battery voltage detection circuit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flying capacitor type voltage detection circuit.
[0002]
[Prior art]
Electric vehicles and hybrid vehicles use high-voltage and large-capacity secondary batteries that store power used as driving energy, and even in fuel-cell vehicles, the use of high-voltage and large-capacity secondary batteries as a buffer for fuel cell output fluctuation is considered suitable. It is done.
[0003]
In the above application, the secondary battery is used in an assembled battery configuration in which a large number of unit cells (hereinafter also simply referred to as cells) are cascaded. For the management measurement of the assembled battery, a predetermined number of one to continuously cascaded batteries are used. Each cell is classified as a module, and the battery voltage is measured for each module.
[0004]
Japanese Patent Application Laid-Open No. 11-248755 proposes a voltage detection technique using a flying capacitor. In this flying capacitor type voltage detection circuit, first, a pair of input side sampling switches are turned on, both ends of the module are connected to both ends of the flying capacitor, and the module voltage is sampled and held in the flying capacitor. Next, after the input side sampling switch is turned off, the pair of output side sampling switches are turned on to apply the storage voltage of the flying capacitor between the pair of input terminals of the differential amplifier circuit.
[0005]
[Problems to be solved by the invention]
In the above-described conventional flying capacitor type voltage detection circuit, the sampling switch needs to increase the capacity of the flying capacitor due to the leakage current when it is off, and to reduce the decrease in the storage voltage of the flying capacitor due to this leakage current. .
[0006]
However, the increase in the capacity of the flying capacitor increases the power consumption of the flying capacitor type voltage detection circuit as compared with that of other assembled battery voltage detection circuits such as a resistance voltage dividing type, and also causes variations in capacity between modules. There was a problem that it was likely to occur.
[0007]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a flying capacitor type voltage detection circuit that realizes a reduction in power consumption.
[0008]
[Means for Solving the Problems]
A driving method of a flying capacitor type assembled battery voltage detection circuit according to the present invention includes a flying capacitor circuit having at least one flying capacitor and N (N > 2) A multiplexer that connects each end of each battery module sequentially to both ends of the flying capacitor circuit for each of the battery modules, and constantly charges the flying capacitor circuit in the same direction by the voltage of each battery module; An amplifier circuit; a pair of output-side sampling switches that individually connect a pair of input terminals of the differential amplifier circuit to both ends of the flying capacitor circuit; and a reset circuit that short-circuits the flying capacitor circuit and attenuates the stored voltage. In the flying capacitor type assembled battery voltage detection circuit, the storage voltage of the flying capacitor circuit is output to the differential amplifier circuit through the output side sampling switch, and the output side sampling switch is turned off to turn off each of the battery modules. Read voltage sequentially After a certain time executing a read cycle to issue, to implement short discharge operation of the flying capacitor circuit according to the reset circuit is characterized by varying the battery module to be read next the short operation in sequence.
[0009]
The flying capacitor circuit is preferably composed of one or two flying capacitors connected in series. The reset circuit is preferably configured by connecting one reset switch and a short-circuit current regulating discharge resistor in series.
[0014]
The operation of reading the voltage of the battery module to the flying capacitor immediately after the reset operation consumes the amount of stored power (storage energy) of the battery module because there is no residual voltage in the same direction in the flying capacitor. Therefore, according to this configuration, the reset operation is performed after the voltage of the battery module is performed many times, so that power consumption of the battery module due to the reset operation can be reduced. Furthermore, in this configuration, the order of the battery modules read immediately after the reset operation is changed in order, so that all the battery modules can be consumed in order by the reset operation, and only a specific battery module is not consumed by the reset operation. .
[0015]
According to the aspect, the flying capacitor is partially discharged (for example, discharged) by the short-circuit discharge operation of the flying capacitor circuit by the reset circuit. Amount 5 (Less than 0%).
[0016]
According to this configuration, the flying capacitor is discharged even after a reset operation. Amount 5 The reset period is set so that the stored voltage of less than 0% remains after reset. If it does in this way, the electrical storage energy of the battery module lost in reading of the voltage of the battery module immediately after reset operation can be reduced.
[0017]
In this case, in normal operation, the voltage variation between the battery modules is less than 50% of the voltage of the battery modules, and therefore the voltage of the battery modules read out to the differential amplifier circuit via the flying capacitor immediately after the reset operation is If it is 50% or less, it is not a drop in the voltage of the battery module but a disconnection failure or off failure of the multiplexer. That It can be determined with certainty. In addition, the voltage of the battery module may be abnormally reduced and may be reduced to 50% or less of the voltage of the battery module read immediately before. In this case, it is not possible to distinguish between a disconnection failure or an off failure of the multiplexer, but in any case, it can be determined that there is some abnormality. Further, in this case, if the reset period is increased in the next reset operation for the battery module determined to be abnormal, the amount of decrease in the stored voltage of the flying capacitor immediately after the reset operation can be increased. It can be done reliably.
[0018]
According to that aspect The turn-on period of the reset circuit is adjusted based on the module voltages read last time.
[0019]
In other words, the voltage of the battery module is read out to the flying capacitor at regular short intervals, and it is impossible for the battery module voltage to change suddenly in such a short period of time. To pressure On the basis of this, when it is read out immediately before the reset operation, the reset period is shortened in such a range that the residual voltage after the reset operation can be distinguished from the voltage of the battery module immediately after and the flying capacitor residual voltage after the reset operation. If it does in this way, the amount of battery module discharge by reset operation can be reduced. Of course, even in this case, if it is determined that the voltage of the battery module read out to the differential amplifier circuit immediately after the reset operation is a disconnection failure or an off-failure, the reset operation period in the next reset operation of this battery module voltage Can be sufficiently extended to perform a determination operation for distinguishing between a disconnection failure, an off failure, and an abnormal battery voltage sudden decrease.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the flying capacitor type voltage detection circuit of the present invention will be described in detail with reference to the following examples.
[0041]
[Example 1]
(Circuit configuration)
A battery pack voltage detection apparatus to which the present invention is applied will be described with reference to a circuit diagram shown in FIG.
[0042]
DESCRIPTION OF SYMBOLS 1 is a battery for driving power storage for hybrid electric vehicles, 2 is a multiplexer, 3 is a flying capacitor circuit composed of one flying capacitor C3, 4 is an output side sampling switch circuit, 5 is a differential amplifier circuit, and 6 is reset The multiplexer 2 reads the signal voltage from the battery 1 to the flying capacitor circuit 3, and the output side sampling switch circuit 4 reads the signal voltage from the flying capacitor circuit 3 to the differential amplifier circuit 5. R20 is a current limiting resistor that limits the discharge current of the flying capacitor circuit 3.
[0043]
The battery 1 is formed by connecting eight battery modules VB10 to VB17 in series.
[0044]
The multiplexer 2 has N + 1 input-side sampling switches whose one ends are individually connected to the highest potential end and the lowest potential end of the battery 1 and the connection ends of the battery modules VB10 to VB17 via current limiting resistors R10 to R18, respectively. The input side sampling switch circuit 21 including SSR10 to SSR18 and the switching circuit 22 that switches the power transmission direction of the signal voltage read from the input side sampling switch 21 circuit and sends the signal voltage to the flying capacitor circuit 3.
[0045]
The switching circuit 22 includes four switches SW00 to SW03 that are analog switches. The switch (first switch) SW00 individually connects the other ends of the odd-numbered switches SSR10, SSR12, SSR14, SSR16, and SSR18 to one end of the flying capacitor C3. The switch (second switch) SW01 individually connects the other ends of the odd-numbered switches SSR10, SSR12, SSR14, SSR16, and SSR18 to the other end of the flying capacitor C3. The switch (third switch) SW02 individually connects the other ends of the even-numbered switches SSR11, SSR13, SSR15, and SSR17 to one end of the flying capacitor C3. Switch (4th switch) SW 03 Respectively connects the other ends of the even-numbered switches SSR11, SSR13, SSR15, and SSR17 to the other end of the flying capacitor C3. By simultaneously turning on the switches SW00 and SW03, the signal voltages of the odd-numbered battery modules VB10, VB12, VB14, VB16, and VB18 are read out to the flying capacitor C3, and the flying capacitor C3 is charged in one direction. By simultaneously turning on the switches SW01 and SW02, the signal voltages of the even-numbered battery modules VB11, VB13, VB15, and VB17 are read out to the flying capacitor C3, and the flying capacitor C3 is charged in one direction. That is, the switching circuit 22 performs the above operation in synchronization with the input side sampling switches SSR10 to SSR18 of the input side sampling switch circuit 21, and always charges the flying capacitor C3 in the same direction by the signal voltage of each of the battery modules VB10 to VB17. .
[0046]
The output side sampling switch circuit 4 includes switches SSR21 and SSR22 as a pair of output side sampling switches. The switch SSR21 connects one end of the flying capacitor C3 to one input end of the differential amplifier circuit 5, and the switch SSR22 is a flying capacitor. The other end of C3 is connected to the other input end of the differential amplifier circuit 5.
[0047]
The differential amplifier circuit 5 is composed of a normal operational amplifier voltage amplifier circuit, Vref is a reference power supply, and the potential of the other input terminal (+ input terminal) of the operational amplifier OP is set to the reference potential through a resistor.
[0048]
The reset circuit 6 includes a reset switch SSR26 and a short-circuit current limiting resistor element R20 connected in series with each other, and is connected in parallel with the flying capacitor C3.
(Basic operation explanation)
The basic operation of the circuit of FIG. 1 will be described below.
[0049]
Each pair of switches SSR10 to SSR18 connected to both ends of each of the battery modules VB10 to VB17 is turned on in turn in the first half period of a predetermined voltage module readout period ΔT repeated at a constant period, and at the same time, the switching circuit 22 The switches SW00 to SW03 are synchronously turned on as described above, and the voltages (also referred to as module voltages) of the battery modules VB10 to VB17 are sequentially read out. In the second half of each predetermined period ΔT, the switches SSR10 to SSR18 are turned off, the switches SSR21 and SSR22 of the output side sampling switch circuit 4 are turned on, and the stored voltage of the flying capacitor C3 is read to the differential amplifier circuit 5.
[0050]
The reset switch SR26 of the reset circuit 6 is turned on at the final stage of the latter half of the voltage module readout period ΔT, and attenuates or erases the stored voltage remaining in the flying capacitor C3. At this time, by adjusting the ON period of the reset switch SR26, the ratio of the residual voltage of the flying capacitor C3 can be determined. The reset operation includes a signal voltage (not including the storage voltage of the battery module) read out to the differential amplifier circuit 5 after the reset operation in a state where the disconnection failure or off failure of the multiplexer 2 occurs, and the battery module having the lowest possible voltage. The residual voltage should be as large as possible within a range that can be distinguished from the voltage (preferably 50 % The above is preferable in terms of reducing the power loss of the battery module.
[0051]
(Disconnection failure and off failure detection operation 1)
With the above operation, the voltages of the battery modules VB10 to VB17 can be sequentially transferred to the differential amplifier circuit 5. If the voltage of the next battery module is read after the reset switch SSR26 is turned on, the multiplexer 2 is disconnected or turned off. If there is a failure, the signal voltage cannot be read from the battery module to the flying capacitor C3, so the signal voltage read from the flying capacitor C3 to the differential amplifier circuit 5 is zero. Therefore, by determining the voltage level of the battery module immediately after the reset switch SSR26 is turned on, it is possible to easily detect a disconnection failure or an OFF failure in the current path of the multiplexer 2 related to the voltage reading of the battery module. .
[0052]
(Disconnection failure and off failure detection operation 2)
When the voltage of all the battery modules VB10 to VB17 is sequentially read from the VB10 to the differential amplifier circuit 5 and a read cycle for reading the voltage of the VB17 is performed, the reset switch (also described as SW1 in the drawing) SSR26 is turned on. Immediately thereafter, the battery module connected to the flying capacitor C3 is discharged due to the charging of the flying capacitor C3. This problem is particularly serious when only certain battery modules are always selected immediately after this reset operation. In addition, it is possible to detect only a disconnection failure or an off failure in the current path connected to the specific battery module.
[0053]
Therefore, the battery module selected immediately after the reset operation is changed in order for each read cycle. Thereby, the capacity variation between battery modules can be reduced.
[0054]
(Modification)
In the above example, all the battery modules are read once in one read cycle period, and the reading order of the battery modules in each read cycle is changed. Instead, the number exceeding the number of battery modules in one read cycle period. May be read out, and some battery modules may be read out twice within one read cycle period. In this case, the reading order of the battery modules is the same. In this way, since the battery modules read immediately after the reset operation are shifted by the number of battery modules to be read an extra number of times, all the battery modules can be evenly arranged immediately after the reset operation. The number of battery modules to be read an extra number is preferably 1. However, it may not be 1 as long as all battery modules are arranged immediately after the reset operation as the cycle is repeated.
[0055]
Alternatively, only the battery module read for the second time corresponding to the battery module for reading this extra number of times may be read for each read cycle.
[0056]
(Reset operation)
If the previous read voltage of the battery module voltage read immediately after the reset operation is stored and the reset period is set so that a voltage smaller than the stored value by a predetermined value remains in the flying capacitor C3, the useless battery module Power loss can be reduced.
[0057]
(Modification)
By changing the number of reset operations or the ON period in accordance with the voltage of the battery module, it is possible to reduce voltage variations among the battery modules VB10 to VB17. That is, the ON period of the reset operation performed immediately before reading the battery module having a large previous read voltage value is lengthened, or the average number of reset operations performed immediately before the battery module having a large previous read voltage value Or the like, the decrease in the storage voltage of the battery module having a large previous read voltage value can be promoted, and the voltage variation can be reduced.
[0058]
(Modification)
In the above embodiment, the reset switch SSR26 is turned on after the output side sampling switches SSR21 and SSR22 of the output side sampling switch circuit 4 are turned off. However, the reset switch SSR26 is turned on and the output side sampling switch circuit 4 is turned on. The side sampling switches SSR21 and SSR22 may be implemented in the second half of the ON period. In this way, the charge remaining in the parasitic capacitance of the signal line connecting the output side sampling switches SSR21, SSR22 and the operational amplifier OP can also be canceled, so that a reduction in reading accuracy due to the residual charge can be reduced.
[0059]
[Example 2]
Another embodiment of the present invention will be described below with reference to FIG.
[0060]
In this embodiment, the consumption of the battery modules VB10 to VB17 due to the flying capacitor C3 is reduced by using a multiplexer in which the switching circuit 22 of the multiplexer 2 shown in FIG. 1 is omitted.
[0061]
In this type of conventional circuit, the switches SSR10 to SSR18 of the input side sampling switch circuit 21 are sequentially turned on in the adjacent order. For this reason, since the battery modules VB10 to VB17 always discharge the residual voltage stored in the reverse direction and then store their own voltage in the flying capacitor C3, the battery modules VB10 to VB17 are greatly consumed.
[0062]
Therefore, in this embodiment, the voltage reading cycle of each battery module is performed as follows to reduce the consumption of the battery module. First, perform an odd read cycle that sequentially reads all the voltages of the odd-numbered battery modules, and then check all the voltages of the even-numbered battery modules. The hand Perform an even read cycle that reads sequentially. In this way, the capacity of the battery module is significantly consumed by the residual voltage in the reverse direction of the flying capacitor C3 only in the first battery module of the odd read cycle and the even read cycle. Therefore, consumption of other battery modules can be reduced.
[0063]
(Modification)
Also in this embodiment, by turning on the reset switch SSR26 (SW1) after turning on the switches SSR21 and SSR22 immediately before the voltage reading of the first battery module in each of the odd read cycle and the even read cycle, Consumption can be reduced.
[0064]
(Modification)
However, also in the second embodiment described above, when the battery modules that are read first in the odd-numbered read cycle and the even-numbered read cycle are always fixed to a part, the voltage variation between the battery modules VB10 to VB17 increases. .
[0065]
Therefore, the battery modules that are read first in the odd read cycle and the even read cycle are changed in turn. Thereby, it is possible to substantially equalize the consumption of the battery modules VB10 to VB17 due to the charge transfer to the flying capacitor C3.
[0066]
Of course, in this case as well, it is preferable to turn on the reset switch SSR 26 before reading the voltage of the battery module first in each of the odd read cycle and the even read cycle, thereby reducing charge carry-out from the battery module.
[0067]
(Modification)
In the above embodiment, a disconnection failure or an off failure (for example, a disconnection or a failure in which the switch of the multiplexer 2 is not turned on)
Each of the odd read cycle and the even read cycle can be performed based on the voltage of the battery module. Alternatively, the reset operation by the reset switch SSR26 is performed at the end of the odd read cycle and the even read cycle, and the read operation is performed immediately thereafter. It can implement based on the voltage of the taken out battery module.
[0068]
(Modification)
In the second embodiment, each odd read cycle is a cycle for reading the voltage of the odd-numbered battery module once, and the even read cycle is a cycle for reading the voltage of the even-numbered battery module once. The number of battery module reads included in one odd read cycle and one even read cycle can be arbitrarily set.
[0069]
For example, in an odd read cycle of the read cycles, voltages of a predetermined combination of odd-numbered battery modules are sequentially read, and thereafter, voltages of a predetermined combination of even-numbered battery modules are sequentially read.
[0070]
Each odd read cycle may include an odd-numbered battery module that is read only once and an odd-numbered battery module that is read multiple times. Similarly, an even-numbered battery module is an even-numbered battery module that is read only once. And even-numbered battery modules that are read a plurality of times, and in addition, all even-numbered battery modules and even-numbered battery modules that are subjected to additional reading can be included. . However, the average probability that each battery module VB10 to VB17 comes immediately after the odd read cycle or the even read cycle and the voltage read frequency of each battery module are equalized as a whole, thereby equalizing the consumption of each battery module VB10 to VB17. can do.
[0071]
Alternatively, each odd read cycle can include a portion of an odd-numbered battery module, and can also include a portion of an even-numbered battery module. The next odd read cycle can include the remainder of the odd-numbered battery modules, and can also include the remainder of the even-numbered battery modules. That is, the voltage reading of the odd-numbered battery modules is completed by a plurality of odd-numbered read cycles, and the voltage reading of the even-numbered battery modules is completed by a plurality of even-numbered read cycles. However, the average probability that the voltage modules VB10 to VB17 come immediately after the odd read cycle or the even read cycle and the voltage read frequency of each battery module are equalized as a whole, thereby reducing the consumption of each battery module VB10 to VB17. Can be equalized.
[0072]
In this example, in particular, the total number of battery module reads in one odd read cycle or one even read cycle of the flying capacitor type assembled battery voltage detection circuit and the actual number of battery modules in the battery 1 are the circuit or Even if there is a mismatch due to the battery design change, there is an advantage that the voltage of each battery module can be read out evenly without any trouble and the consumption of each battery module can be equalized.
[0073]
(Modification)
In the above modification, the voltage of each battery module is read as a whole at an equal frequency, regardless of the mismatch between the number of battery modules of the battery 1 and the number of battery module readings performed in one reading cycle, and this reading is performed. The battery module consumption was averaged at, but a complete odd read cycle that reads the voltages of all odd-numbered battery modules and a full-even read cycle that reads the voltages of all even-numbered battery modules were first executed. Later, a partial read cycle can be performed in which a predetermined combination of odd-numbered battery modules or even-numbered battery modules is additionally read. Even in this case, the battery modules read immediately after changing the reading of at least the odd-numbered battery modules and the reading of the even-numbered battery modules are changed in order, and the consumption levels of the battery modules VB10 to VB17 are averaged. Is done. In this case, the direction in which the battery module read in the additional partial read cycle charges the flying capacitor C3 is the same as the flying capacitor charge direction in the immediately preceding odd-numbered (or even-numbered) read cycle. However, it is important in reducing the consumption of the battery module.
[0074]
(Determination of disconnection failure and off failure)
The disconnection failure or off-failure determination in this embodiment can be performed based on the voltage of the battery module made immediately after the odd read cycle and the even read cycle. In addition, when a reset operation is performed immediately before the voltage reading of the battery module that is performed immediately after the odd read cycle and the even read cycle, a disconnection failure or an off failure is performed based on the voltage of the battery module that is performed immediately after the reset operation. Can be detected.
[0075]
That is, if the voltage of the battery module immediately after the above is a reverse voltage or the voltage of the flying capacitor C3 after reset less than a predetermined value, the voltage is normally read from the battery module immediately after the above. It can be determined that there is no.
[0076]
[Example 3]
Another embodiment of the present invention will be described below with reference to FIG.
[0077]
This embodiment is different from the first embodiment shown in FIG. 1 in that the flying capacitor circuit 3 is composed of two flying capacitors C3 and C3 ′ connected in series, and the reset circuit 6 is the same as the reset circuit 6 in FIG. The first reset circuit 6x and the second reset circuit 6y are configured such that the first reset circuit 6x is connected in parallel to the flying capacitor C3, the second reset circuit 6y is connected in parallel to the flying capacitor C3 ′, and the flying capacitors C3 having substantially the same capacity are connected. , C3 ′ is connected to the reference power source Vref through the switch SSR23. The first reset circuit 6x includes a reset switch SSR26a (SW2) and a resistance element R26a, and the second reset circuit 6y includes a reset switch SSR26b (SW3) and a resistance element R26b.
[0078]
The operation of this circuit will be described. In this circuit, the multiplexer 2 stores the voltage ΔVs of the battery module in half in the flying capacitors C3 and C3 ′. Thereafter, the switches SSR21, SSR22, SSRW23 are turned on, and the signal voltages of the flying capacitors C3, C3 ′ are read out to the differential amplifier circuit 5. In this way, a potential that is higher by 0.5 ΔVs than the reference potential of the reference power source Vref and a potential that is lower by 0.5 ΔVs are applied to the pair of input ends of the differential amplifier circuit 5. The influence of the parasitic capacitance can be reduced, and the input voltage of the differential amplifier circuit 5 can be accurately swung to both sides using the reference voltage of the reference potential source Vref as an intermediate voltage value.
[0079]
In the circuit of FIG. 3, similarly to the first and second embodiments, the consumption of each battery module can be averaged and disconnection failure or off failure determination can be performed.
[0080]
[Example 4]
Another embodiment of the present invention will be described below with reference to FIG.
[0081]
In this embodiment, in FIG. 3, the reset circuit 6 is constituted by the reset switch SSR26 and the current limiting resistor R20 shown in FIG. 1, and the output side sampling switch circuit 4 ′ is constituted by three output side sampling switches SSR21, SSR22, and SSR23. The differential amplifier circuit 5 'is provided with differential amplifier circuits 5a and 5b equivalent to the differential amplifier circuit 5 shown in FIG.
[0082]
The differential amplifier circuit 5a detects the storage voltage of the flying capacitor C3 through the output side sampling switches SSR21 and SSR22, and the differential amplifier circuit 5b detects the flying capacitor C through the output side sampling switches SSR23 and SSR22. 4 Is detected.
[0083]
According to this circuit configuration, the voltages of the battery modules VB10, VB13, VB14, and VB17 are detected by the differential amplifier circuit 5a after charging the flying capacitor C3 in the same direction, and the voltages of the battery modules VB11, VB12, VB15, and VB16 are detected. Is the flying capacitor C 4 Are detected in the same direction and then detected by the differential amplifier circuit 5b. According to this circuit. Flying capacitors C3, C without switching circuit 4 The charging direction can be aligned. Also in this circuit, by adopting the same method as in the first embodiment, it is possible to reduce the disconnection failure, off failure, and consumption of the battery module.
[Brief description of the drawings]
FIG. 1 is a circuit diagram illustrating a flying capacitor type voltage detection circuit according to a first embodiment;
FIG. 2 is a circuit diagram illustrating a flying capacitor type voltage detection circuit according to a second embodiment; FIG. 6 is a circuit diagram illustrating a modification of the first embodiment.
FIG. 3 is a circuit diagram showing a flying capacitor type voltage detection circuit according to a third embodiment;
4 is a circuit diagram showing a flying capacitor type voltage detection circuit according to a fourth embodiment; FIG.
[Explanation of symbols]
1 battery
2 Multiplexer
3 Flying capacitor circuit
4 Output side sampling switch circuit
5 Differential amplifier circuit

Claims (4)

A flying capacitor circuit having at least one flying capacitor;
Both ends of N (N > 2) battery modules that are connected in series to form an assembled battery are sequentially connected to both ends of the flying capacitor circuit for each of the battery modules, and the flying capacitors are generated by the voltages of the battery modules. A multiplexer that always charges the circuit in the same direction;
A differential amplifier circuit;
A pair of output side sampling switches for individually connecting a pair of input terminals of the differential amplifier circuit to both ends of the flying capacitor circuit;
A reset circuit that short-circuits the flying capacitor circuit and attenuates the stored voltage;
In a driving method of a flying capacitor type assembled battery voltage detection circuit comprising:
The voltage of the battery module is read into the flying capacitor circuit through the multiplexer, the storage voltage of the flying capacitor circuit is output to the differential amplifier circuit through the output side sampling switch, and the output side sampling switch is turned off to turn off the output side sampling switch. After carrying out a read cycle for sequentially reading the voltage of each battery module a certain number of times, performing a short-circuit discharge operation of the flying capacitor circuit by the reset circuit,
The method of driving a flying capacitor type assembled battery voltage detection circuit, wherein the battery modules read out next to the short circuit operation are changed in order. In the driving method of the flying capacitor type assembled battery voltage detection circuit according to claim 1,
A driving method of a flying capacitor type assembled battery voltage detection circuit, wherein the flying capacitor is partially discharged by the short-circuit discharge operation of the flying capacitor circuit by the reset circuit. In the driving method of the flying capacitor type assembled battery voltage detection circuit according to claim 1,
The driving method of the flying capacitor type battery pack voltage detection circuit, characterized in that to partial discharge in the range of less than the flying or capacitor power storage voltage al 50% by the short discharging operation of the flying capacitor circuit by said reset circuit . In the driving method of the flying capacitor type assembled battery voltage detection circuit according to any one of claims 2 and 3,
A driving method of a flying capacitor type assembled battery voltage detection circuit, characterized in that a turn-on period of the reset circuit is adjusted based on each module voltage read last time.

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