KR100873512B1 - Battery level measuring device and method - Google Patents

Abstract

An apparatus and method for measuring battery level are disclosed. According to an embodiment of the present invention, a battery remaining amount measuring device for measuring the remaining amount of the battery for supplying power to the electronic device, comprising: a voltage detector for detecting the output voltage value of the battery; A voltage compensator for measuring an amount of load current supplied from the battery to each load of the electronic device and outputting a voltage compensation value according to the measured load current amount; And an operation unit configured to receive the output voltage value and the voltage compensation value, add the voltage compensation value to the output voltage value, and calculate a battery remaining amount corresponding to the addition result. According to the present invention, it is possible to more accurately measure and display the remaining battery capacity by applying a voltage compensation value according to the measured load current amount to the detected battery output voltage.

Description

Apparatus and method for gauging remainder of battery}

1 is a block diagram showing the configuration of a battery level measuring device according to the prior art.

Fig. 2 is a block diagram briefly showing the configuration of a mobile phone as an example of use of the battery remaining amount measuring device of the present invention.

Figure 3 is a block diagram showing the configuration of the battery remaining amount measuring apparatus according to an embodiment of the present invention.

4 is a flowchart illustrating a method of measuring remaining battery capacity according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: battery 200: battery level measuring device

210: voltage detector 220: voltage compensator

230: signal converter 240: calculator

225: current measuring device 226: sense resistor

300: power distribution unit

The present invention relates to a battery level measurement technology, and more particularly, in the battery level measurement in an electronic device, a battery capable of measuring battery level more accurately by applying a voltage compensation value according to a load current amount in addition to a voltage measurement method. A residual amount measuring apparatus and method are provided.

1 is a block diagram of a battery remaining amount measuring apparatus according to the prior art. Referring to FIG. 1, a battery level measuring device according to the related art is detected by a voltage divider 20 and a voltage divider 20 for dividing and detecting a voltage output from a battery 10 and a battery at a predetermined ratio. A / D converter 30 which receives the inputted (distributed) voltage (analog signal) and converts it into a digital signal, and reads the data (information on detection voltage) output from the A / D converter 30 and corresponds to it. It is comprised by the calculation device 40 which calculates (decides) the battery residual quantity to be made.

However, there is a problem that the battery level measuring apparatus according to the related art shown in FIG. 1 does not consider a battery voltage drop according to a load current applied to the entire electronic device. That is, the reason why the voltage drop value of the battery when the electronic device is under a small load and the voltage drop value of the battery when the big load is applied are different. There was a problem in that a battery voltage swing occurred. This will be described with an example of a mobile phone as follows.

The load current amount when the mobile phone is in a call waiting state (when a small load is applied to the mobile phone) has a small value within approximately 10 mA, and the load current amount when it is in a busy state (when the mobile phone is under heavy load) is approximately It has a large value of more than 300mA. According to the experimental results, the battery voltage drop generated when a load current of about 100 mA flows in the mobile phone corresponds to approximately 0.09 V. Thus, a battery voltage drop of 0.009 V occurs in a call waiting state and 0.27 in a busy state. A battery voltage drop of V will occur.

Therefore, the battery voltage bar shows the battery level on the LCD of the mobile phone from 4 to 3, the threshold voltage level is 3.8V, and the battery voltage in standby state just before the call is 3.85. Assuming that V, the battery bar was measured at 3.58V in successive calls (because the battery voltage drop of 0.27V is caused by a large load current of about 300mA or more flowing through the mobile phone). Or go down two spaces. At this time, if the user briefly terminates the call with the other party and there is no significant change in the actual battery voltage, when the mobile phone returns to the standby state, the measured battery voltage has a value similar to 3.85V, and the battery bar is replaced by 4 spaces. Problem occurs (battery voltage swing phenomenon). The battery voltage swing phenomenon is a major factor that causes the user to disbelief about the remaining battery indication.

In order to solve the above-described battery voltage swing phenomenon, a conventional method for measuring the remaining battery capacity includes a voltage compensation method for each event. The event-based voltage compensation method uses a method of compensating the corresponding voltage compensation value to the measured battery voltage value whenever each event occurs in the electronic device in order to reduce the inaccuracy of the remaining battery indication due to the battery voltage swing phenomenon. will be. For example, if a 200mA load current flows experimentally to drive the LCD module of a mobile phone, the corresponding voltage compensation value (inverse 0.18V) is added to the measured battery voltage when the LCD module is driven. However, in this event-specific voltage compensation method, since each voltage compensation value to be compensated for each event that may occur in the electronic device must be set in advance from the design time, all events of various unpredictable conditions occurring in the electronic device There was a limit to the inability to respond appropriately.

The present invention provides a battery remaining amount measurement device and method that can be more accurate battery remaining amount measurement by using a method of adding the voltage compensation value according to the load current amount to the detected battery output voltage.

In addition, the present invention provides a battery remaining amount measuring device and method that can give the user of the electronic device reliability of the remaining battery indication by preventing the battery voltage swing phenomenon through accurate battery remaining measurement.

In addition, the present invention by using the voltage compensation method according to the real-time measured load current amount, it is possible to accurately measure the remaining amount of the battery as compared to the conventional method of performing voltage compensation for each event generated in the electronic device, as well as the remaining battery capacity simple design and implementation A measuring device and method are provided.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the present invention, a battery remaining amount measuring device for measuring the remaining amount of the battery for supplying power to the electronic device, comprising: a voltage detector for detecting the output voltage value of the battery; A voltage compensator configured to measure an amount of load current supplied from the battery to each load of the electronic device, and output a voltage compensation value according to the measured load current amount; And a calculator configured to receive the output voltage value and the voltage compensation value and calculate a battery remaining amount corresponding to a result obtained by adding the voltage compensation value to the output voltage value.

Here, the voltage detector may be implemented by a voltage distribution circuit connected to the battery.

Here, the signal conversion unit for converting an analog signal into a digital signal further,

The output voltage value and the voltage compensation value may be binarized by the signal converter and input to the calculator.

Here, the signal converter may perform binary operation by comparing the output voltage value and the voltage compensation value with a preset reference voltage value. In this case, the reference voltage value may be set to a buffer voltage value of the battery.

Here, the voltage compensator includes a power distribution device for distributing the power supplied from the battery to each of the load and a current measuring circuit for measuring the current between the battery, the load current amount is measured by the current measuring circuit It can be determined by the amount of current.

Here, a sensing resistor is disposed on a connection line connecting the power distribution device and the battery, and the current measuring circuit detects a voltage across the sensing resistor to measure a current between the power distribution device and the battery. have.

The apparatus may further include a storage unit configured to store the calculated battery remaining amount.

Here, the calculator may output the calculated information on the remaining battery level as an external signal, and the information on the remaining battery level may be transmitted to and displayed by the external signal.

Here, the detection of the output voltage value and the measurement of the total load current amount may be made at predetermined intervals.

According to another aspect of the present invention, a battery remaining amount measuring method for measuring the remaining amount of the battery for supplying power to the electronic device by the battery remaining amount measuring device, (a) detecting the output voltage value of the battery; (b) measuring an amount of load current supplied from the battery to each load of the electronic device; (c) outputting a voltage compensation value according to the measured load current amount; And (d) calculating a battery remaining amount corresponding to a sum result of summing the voltage compensation value with the output voltage value.

Here, after the step (c) and before the step (d), the method further comprises the step of (e) converting the analog signal into a digital signal, wherein the output voltage value and the voltage compensation value are determined by the step (e). Can be binarized.

Here, the binarization through step (e) may be performed by comparing the output voltage value and the voltage compensation value with a preset reference voltage value. In this case, the reference voltage value may be set to a buffer voltage value of the battery.

Here, the measurement of the load current amount through the step (b) may be by measuring the current between the battery and the power distribution device for distributing the power supplied from the battery to each load.

Here, the measurement of the current between the power distribution device and the battery may be by detecting the voltage across the sensing resistor disposed on the connection line connecting the power distribution device and the battery.

Here, after the step (d), (f) may further comprise the step of storing the calculated battery remaining amount.

Here, after the step (d), (g) may further include the step of outputting the calculated battery remaining amount as an external signal to the display unit.

Here, the detection of the output voltage value of step (b) and the measurement of the load current amount of step (c) may be performed at predetermined periodic intervals.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram schematically showing the configuration of a mobile phone as an example of use of the battery remaining amount measuring apparatus of the present invention. Herein, all the descriptions below FIG. 2 will be described using the case of a mobile phone as an example, but the battery level measuring device and method of the present invention require a display of the battery level, including a laptop, a camcorder, a digital camera, an MP3, a PMP, or the like. Or any electronic device capable of displaying the battery level can be applied without any limitation.

2 shows a relationship between the battery level measuring device 200 and other components of the present invention included in the mobile phone. Here, the display unit 110, the imaging unit 120, the key input unit 130, the handset 140, the wireless unit 150 and the control unit 160 corresponds to the general components provided in the mobile phone, the present invention Since this is irrelevant to the gist of the detailed description thereof will be omitted. The battery 100 supplies power to each load (each component shown in FIG. 2) of the mobile phone, and the power distribution device 300 requires each load (each component) to supply power from the battery 100. Function to distribute appropriately according to voltage value or current value. The battery remaining amount measuring device 200 of the present invention is connected to the battery 100 and the power distribution device 300 to measure the remaining amount of the battery 100. A more detailed description of the battery level measuring device 200 of the present invention will be described later with reference to FIG. 3.

3 is a block diagram showing the configuration of the battery remaining amount measuring apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the battery level measuring device 200 according to an embodiment of the present invention includes a voltage detector 210 and a voltage compensator 220 and a signal converter 230 including a current measuring device 225. , A calculator 240, and a storage 250.

The voltage detector 210 detects an output voltage value output from the battery 100. For example, when the voltage detector 210 is implemented as a voltage divider using two resistors R ₁ and R ₂ as shown in FIG. 3, the output voltage value detected by the voltage detector 210 may be The battery voltage V _BAT may be a voltage value divided by a ratio by the voltage distribution circuit (see V1 in FIG. 3). However, the voltage detector 210 may be implemented by a method different from that shown in FIG. 3, and the battery voltage V _BAT itself may be detected as an output voltage. At this time, the output voltage value detected by the voltage detector 210 is input to the signal converter 230.

The voltage compensator 220 measures the total load current amount supplied from the battery 100 to each load of the mobile phone, and outputs a voltage compensation value according to the measured load current amount.

To this end, in the battery level measuring device 200 of the present invention, a sensing resistor 226 may be disposed on a connection line connecting the battery 100 and the power distribution device 300, and in the voltage compensator 220. A current measuring device 225 may be provided to detect a voltage across the sensing resistor 226 to measure a current flowing between the battery 100 and the power distribution device 300. As such, the voltage compensator 220 measures the current flowing between the battery 100 and the power distribution device 300 by using the predetermined current measurement device 225, and thus the power distribution device 300 from the battery 100. Through this, the total load current supplied to each load of the mobile phone can be measured (checked).

In this case, the measured load current amount is converted into a voltage compensation value corresponding to the voltage compensation unit 220 and input to the signal conversion unit 230 (see V ₂ of FIG. 3). For example, if the measured load current amount is 100 mA, the experimental battery voltage drop value 0.09 V as described above may be determined as a voltage compensation value and input to the signal converter 230.

The signal converter 230 converts an analog signal into a digital signal. In general, since the computing unit 240 to be described later in an electronic device is implemented as a digital computing device such as a microprocessor, signal conversion processing by a digital conversion device such as an A / D converter is required. That is, since both the output voltage value V ₁ detected from the voltage detector 210 and the voltage compensation value V ₂ output from the voltage compensator 220 are analog signals, the output voltage value V ₁ is converted into a binary value and then the calculation unit ( 240). Here, the binarized value is not limited to binary numbers but includes all types of values recognizable by digital devices as expressed in octal, hexadecimal, and the like.

In this case, the signal converter 230 may convert the input output voltage value V ₁ and the voltage compensation value V ₂ into a comparison operation with a preset reference voltage value. In this case, the reference voltage value used for signal conversion may be set to a buffer voltage value of the battery 100 included in the electronic device or another voltage value corresponding thereto. For example, the detected output voltage value V ₁ is 4.2V, the set reference voltage value is 4.5V, and 8 bits of data (ie, 0 to 255 are binarized by the calculation unit 240, Assuming that a decimal representation of 0 to 255 is input for convenience of display, the output voltage value V ₁ is set to 238 ([4.2 / 4.5] x through a comparison operation by the signal converter 230). 255 may be converted and input to the operation unit 240.

The calculator 240 receives the output voltage value V ₁ and the voltage compensation value V ₂ , which are binarized and transmitted by the signal converter 230, and inputs the voltage compensation value (V) to the output voltage value V ₁ . Calculate the battery level corresponding to the sum of V ₂ ). For example, when the sum result is 238 (ie, 4.2 V), the calculation unit 240 performs a percentage calculation based on 255 (ie, corresponding to 4.5 V of the buffer voltage value) to perform a battery calculation. The remaining amount can be calculated. Alternatively, other methods may be used, such as calculating the remaining battery capacity using the discharge characteristic curve of the used battery.

In addition, the calculator 240 may transmit predetermined information about the calculated battery remaining amount to the display unit 110 of FIG. 2 through an external signal. In this case, the predetermined information about the remaining battery level delivered to the display unit 110 may be information about the remaining battery level itself, but alternative information corresponding to the calculated remaining battery level (for example, remaining usable time information and a battery bar section). Information, etc.).

The storage unit 250 may store information on the remaining battery amount calculated by the calculator 240, or store predetermined data necessary for the operation of the voltage compensator 220, the signal converter 230, and the calculator 240. Can be. 3 illustrates a case in which the storage unit 250 is provided in the battery remaining amount measuring device 200 according to the present invention, but may be separately provided to the outside.

Hereinafter, a method of measuring a battery remaining amount using the battery remaining amount measuring device 200 of the present invention will be described with reference to the flowchart of FIG. 4.

Each component of the battery level measuring device 200 according to the present invention has been described in detail above with reference to FIG. 3, and a redundant description thereof will be omitted. Hereinafter, specific numerical examples will be described.

Before explaining numerical examples, some conditions and situations assumed in the following description are first disclosed. First, it is assumed that the current state of the cellular phone is in a state of being talked by the user (i.e., a heavy load of 300 mA or more of load current). In addition, it is assumed that the actual battery voltage (that is, the accurate battery output voltage V ₁ when the voltage drop according to the load current amount does not occur at all) is 4.2V. In addition, it is assumed that the buffer voltage value of the battery 100 is 4.5V. In addition, it is assumed that the first resistor R ₁ and the second resistor R ₂ of the voltage detector 210 are 300 mW and 200 mW, respectively.

In addition, in the flowchart of FIG. 4, the measuring step of the load current amount in step S420 and the step of outputting the voltage compensation value in step S430 are shown as proceeding after the detection step of the output voltage value in step S410, but this is the case in each step. It is merely to describe the description separately, it will be clear that step S420 and step S430 is performed in parallel with step S410. That is, the detection of the output voltage value in step S410 and the measurement of the load current amount in step S420 (or the output of the voltage compensation value in step S430) may be performed in real time, for example, at equal intervals.

Referring to step S410 of FIG. 4, the voltage detector 210 detects an output voltage value of the battery 100.

At this time, the actual battery voltage is 4.2V, but the battery voltage (V _BAT ) is 3.93V due to the corresponding voltage drop (that is, the voltage drop of 0.27V corresponding to the load current of 300mA) because the mobile phone is in a call state. Becomes Therefore, the output voltage V ₁ detected by the voltage detector 210 becomes 1.572V as shown in Equation 1 below, which is input to the signal converter 230.

Referring to step S420 of FIG. 4, the voltage measuring device 225 provided in the voltage compensator 220 measures the amount of load current supplied from the battery 100 to each load. By this step, the battery remaining amount measuring device 200 of the present invention can find out that the total load current flowing from the battery 100 to the respective loads through the power distribution device 300 in the current state of a call is 300 mA.

Referring to step S430 of FIG. 4, the voltage compensator 220 outputs a voltage compensation value according to the measured load current amount. For example, 0.108V (= 0.27 × [2/5]) obtained by calculating the experimental voltage drop value 0.27V corresponding to the measured load current amount 300mA by the same partial pressure ratio as in Equation 1 above is calculated as the voltage compensation value ( V ₂ ), which is input to the signal converter 230.

Referring to step S440 of FIG. 4, the signal converter 230 compares the input output voltage value V ₁ and the voltage compensation value V ₂ with a preset reference voltage value, respectively, and converts them into a binary digital signal. .

Here, the preset reference voltage value may be a buffer voltage value of the battery 100 or a voltage value corresponding thereto. For example, when the battery buffer voltage value is 4.5V, the reference voltage value is set by the same divided voltage ratio as in Equation 1 above. The calculated 1.8V (= 4.5 x [2/5]) can be set as the reference voltage value. Accordingly, when the output voltage value V ₁ and the voltage compensation value V ₂ are 1.572V and 0.108V according to the above-described example, the digital signals transmitted to the calculator 240 through the signal converter 230 are respectively. 8-bit data corresponding to 222.7 (= [1.572 / 1.8] × 255) and 15.3 (= [0.108 / 1.8] × 255).

Referring to step S450 of FIG. 4, the calculator 240 receives the output voltage value V ₁ and the voltage compensation value V ₂ transferred from the signal converter 230, and then adds the remaining battery amount corresponding to the sum result. Calculate According to the above-described example, when the transmitted output voltage value V ₁ and the voltage compensation value V ₂ are 222.7 and 15.3, respectively, the operation unit 240 may have a remaining battery amount corresponding to 238 which is a result of summing them up. For example, 93% of the fully charged battery value by the percentage calculation can be calculated. In addition, the sum result 238 corresponds to 4.2V when the battery buffer voltage value 4.5V is converted again, which is the same as the actual battery voltage value.

As described above, the information about the remaining battery amount calculated as described above may be stored in the storage 250 after being transferred or transmitted to the display 110 by an external signal for display.

As described above, the present invention can accurately compensate the voltage drop value according to the method of directly measuring the load current amount for each situation of the electronic device through steps S420 and S430 of FIG. 4. Therefore, according to the battery remaining amount measuring apparatus and method of the present invention, it is possible to ensure accuracy and reliability in measuring the remaining amount of battery, and the battery voltage swing phenomenon does not occur even when the load current amount changes instantaneously for each situation of the electronic device. There is an advantage.

On the other hand, according to the conventional method for measuring the remaining battery capacity shown in FIG. 1, since there are no steps such as steps S420 and S430 of the present invention, the voltage drop value according to the load current amount cannot be compensated. That is, assuming that the same conditions and conditions as in the present invention (i.e., the current state of the mobile phone is in a call state and the actual battery voltage is 4.2V) are applied, according to the conventional method shown in FIG. Due to the voltage drop of 0.27V according to the amount of current, the battery voltage is incorrectly measured as 3.93V. In addition, when the load current fluctuates to 10mA, the battery voltage is measured again similar to the actual battery voltage of 4.2V, so that the battery voltage swing phenomenon cannot be overcome and the user may cause distrust in the remaining battery indication. do. In addition, even in the case of the event-specific voltage compensation method, which is another conventional battery level measurement method, it may not be properly handled as described above.

As described above, according to the battery remaining amount measuring apparatus and method of the present invention, a more accurate remaining amount of battery can be measured by using a method of adding a voltage compensation value according to the load current amount to the detected battery output voltage.

In addition, the present invention has an effect that can give the user of the electronic device the reliability of the remaining battery display by preventing the battery voltage swing phenomenon through accurate battery remaining measurement.

In addition, the present invention by using the voltage compensation method according to the amount of load current measured in real time, it is possible to measure the remaining amount of accurate compared to the conventional method of performing voltage compensation for each event generated in the electronic device, as well as the simple design and implementation have.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be readily understood that modifications and variations are possible.

Claims (19)

In the battery level measuring device for measuring the remaining amount of the battery for supplying power to the electronic device, A voltage detector configured to detect an output voltage value of the battery; A voltage compensator configured to measure an amount of load current supplied from the battery to each load of the electronic device, and output a voltage compensation value according to the measured load current amount; A signal converter configured to receive the output voltage value and the voltage compensation value and compare the result with a preset reference voltage value and output a binary output voltage value and a binary voltage compensation value; And An operation unit configured to receive the binary output voltage value and the binary voltage compensation value and calculate a battery remaining amount corresponding to a result obtained by adding the binary voltage compensation value to the binary output voltage value; Battery level measuring device comprising a. The method of claim 1, And the voltage detector is implemented by a voltage distribution circuit connected to the battery. delete delete The method of claim 1, And the reference voltage value is set to a buffer voltage value of the battery. The method of claim 1, The voltage compensator includes a power distribution device for distributing power supplied from the battery to the respective loads and a current measurement circuit for measuring a current between the battery, And the load current amount is determined by the amount of current measured by the current measurement circuit. The method of claim 6, A sensing resistor is disposed on a connection line connecting the power distribution device and the battery, The current measuring circuit detects the voltage across the sensing resistor to measure the current between the power distribution device and the battery. The method of claim 1, And a storage unit for storing the calculated battery remaining amount. The method of claim 1, The operation unit outputs the information on the calculated battery remaining amount as an external signal, The remaining battery information measuring device is characterized in that the transmission to the display unit by the external signal and displayed. The method of claim 1, And detecting the output voltage value and measuring the load current amount at predetermined cycle intervals. In the battery level measuring method, wherein the battery level measuring device measures the remaining amount of a battery that supplies power to an electronic device, (a) detecting an output voltage value of the battery; (b) measuring an amount of load current supplied from the battery to each load of the electronic device; (c) outputting a voltage compensation value according to the measured load current amount; (d) receiving the output voltage value and the voltage compensation value and performing a comparison operation with a preset reference voltage value to output a binary output voltage value and a binary voltage compensation value; And (e) calculating a battery remaining amount corresponding to the result of the sum of the binary voltage compensation value and the binary output voltage value; Battery level measurement method comprising a. delete delete The method of claim 11, And the reference voltage value is set to a buffer voltage value of the battery. The method of claim 11, The measurement of the load current amount through the step (b) is a battery level measuring method, characterized in that by measuring the current between the battery and the power distribution device for distributing the power supplied from the battery to each load. The method of claim 15, And measuring current between the power distribution device and the battery by detecting a voltage across the sensing resistor disposed on a connection line connecting the power distribution device and the battery. The method of claim 11, After step (d) above, and (f) storing the calculated battery remaining amount. The method of claim 11, After step (d) above, and (g) outputting the calculated information regarding the remaining battery level as an external signal and transferring the information to the display unit. The method of claim 11, The detection of the output voltage value of step (b) and the measurement of the load current amount of step (c) are carried out at predetermined cycle intervals.

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