Discharge control circuit, battery management chip, system and module

Abstract

The utility model discloses a discharge control circuit, a battery management chip, a system and a module, and the discharge control circuit comprises a first voltage conversion module which provides a first output voltage to a load connection end; the load detection module is used for driving the first voltage conversion module to enter a non-working state and the second voltage conversion module to enter a working state when the load current output by the load connection end is smaller than a preset current threshold value; the second voltage conversion module is used for providing a target voltage to the load connection end and driving the first voltage conversion module to enter a working state when the load connection end is connected to a load device. According to the technical scheme, when the load connecting end is connected to the load equipment through the second voltage conversion module, the target voltage is provided for compensating the discharge voltage of the load connecting end, the discharge voltage is prevented from dropping, the large-current discharge requirement is met through the first voltage conversion module, and therefore low power consumption is guaranteed, and meanwhile the service life is prolonged. Discharge voltage drop when the load connection end is connected to load equipment is prevented.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a discharge control circuit, battery management chip, system and module. BACKGROUND

[0002] With the progress of science and technology, the cost of lithium battery reduces and the environmental protection consciousness enhances, and people's demand for the lithium battery of recyclable charging increases day by day. Under this background, the application of lithium battery instead of traditional dry battery is more and more widely. However, the use scene of traditional dry battery is mostly remote controller, electronic calculator, electric automobile and other electronic products, and a remarkable feature of these products is occasional use, and the requirement of static power consumption is higher.

[0003] The existing lithium battery conversion dry battery PMIC (power management integrated circuit) chip meets the market demand to some extent, but it still has certain technical defects. It is specifically shown in the following aspects: when the no-load discharge works, the static power consumption of the existing PMIC chip is relatively large, usually greater than 10uA. This leads to the high energy consumption of the product in standby state, which affects the endurance of the product. When discharging, when the load end occurs transient jump (such as from no load to full load), the output voltage will drop greatly, which affects the normal use of the product. UTILITY MODEL CONTENTS

[0004] The utility model embodiment provides a discharge control circuit, battery management chip, system and module to solve the problem that the static power consumption of the existing discharge control circuit is large, and the output voltage drops greatly when the load jumps.

[0005] A discharge control circuit, comprising a first voltage conversion module, a load detection module and a second voltage conversion module;

[0006] The first voltage conversion module is used for connecting the battery and the load connection end, and is used for providing the first output voltage to the load connection end;

[0007] The load detection module is connected with the first voltage conversion module and the second voltage conversion module, and is used for driving the first voltage conversion module into non-working state and driving the second voltage conversion module into working state when the load current output by the load connection end is less than the preset current threshold;

[0008] The second voltage conversion module is connected with the first voltage conversion module, and is used for connecting the battery and the load connection end, and is used for providing the target voltage to the load connection end and driving the first voltage conversion module into working state when the load device is connected to the load connection end.

[0009] Further, the second voltage conversion module comprises a voltage comparison module and a logic output module.

[0010] The voltage comparison module is connected with the load detection module, the load connection end and the first voltage conversion module, and is configured to output a first comparison signal when a measured voltage output by the load connection end is less than a first voltage threshold, and output a second comparison signal when the measured voltage is less than a second voltage threshold; the second voltage threshold is less than the first voltage threshold; and the second comparison signal is used to drive the second voltage conversion module to enter a working state.

[0011] The logic output module is connected with the voltage comparison module and the load connection end, and is configured to provide a target voltage to the load connection end according to the first comparison signal or the second comparison signal.

[0012] Further, a difference between the second voltage threshold and the first voltage threshold ranges from 95 millivolts to 105 millivolts.

[0013] Further, the second voltage conversion module further comprises a reference voltage module, the reference voltage module is connected with the voltage comparison module, and is configured to provide a first reference voltage corresponding to the first voltage threshold and a second reference voltage corresponding to the second voltage threshold to the voltage comparison module.

[0014] Further, the voltage comparison module comprises a first comparator and a second comparator.

[0015] The first input end of the first comparator is connected with the reference voltage module, the second input end of the first comparator is connected with the load connection end, the enable end of the first comparator is connected with the load detection module, and the output end of the first comparator is connected with the logic output module.

[0016] The first input end of the second comparator is connected with the reference voltage module, the second input end of the second comparator is connected with the load connection end, the enable end of the second comparator is connected with the output end of the first comparator, and the output end of the second comparator is connected with the logic output module and the first voltage conversion module.

[0017] Further, the first voltage conversion module comprises a Buck module; and the second voltage conversion module comprises an LDO module.

[0018] A battery management chip comprises the discharge control circuit.

[0019] Further, the battery management chip further comprises a charge control circuit; the charge control circuit is configured to connect a battery and a load connection end, and is configured to perform charge control on the battery.

[0020] A battery management system comprises a battery and the battery management chip; the battery is connected with the battery management chip.

[0021] A battery module comprises the battery management system.

[0022] The discharge control circuit, the battery management chip, the system and the module, the discharge control circuit comprises a first voltage conversion module, a load detection module and a second voltage conversion module; the first voltage conversion module is used for connecting the battery and a load connection end, and is used for providing a first output voltage to the load connection end; the load detection module is connected with the first voltage conversion module and the second voltage conversion module, and is used for driving the first voltage conversion module to enter a non-working state and driving the second voltage conversion module to enter a working state when a load current output by the load connection end is less than a preset current threshold; the second voltage conversion module is connected with the first voltage conversion module, and is used for connecting the battery and the load connection end, and is used for providing a target voltage to the load connection end and driving the first voltage conversion module to enter the working state when a load device is connected to the load connection end, so that the target voltage is provided by the second voltage conversion module to compensate for the discharge voltage of the load connection end when the load device is connected to the load connection end, and the discharge voltage drop is prevented, and the first voltage conversion module is driven to enter the working state to meet the large-current discharge demand through the first voltage conversion module, so that the discharge voltage drop when the load device is connected to the load connection end is prevented while the low power consumption is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will be briefly introduced the drawings needed to be used in the description of the embodiments of the utility model, obviously, the drawings in the following description only some embodiments of the utility model, for those skilled in the art, under the premise of not paying the creative labor, other drawings can also be obtained according to these drawings.

[0024] Figure 1 It is a circuit schematic diagram of the battery management system in an embodiment of the utility model;

[0025] Figure 2 It is another circuit schematic diagram of the battery management system in an embodiment of the utility model.

[0026] In the drawing: 1, battery;2, battery management chip;21, discharge control circuit;211, first voltage conversion module;212, load detection module;213, second voltage conversion module;2131, voltage comparison module;213a, first comparator;213b, second comparator;2132, logic output module;2133, reference voltage module;22, charge control circuit. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present application.

[0028] It should be understood that the present application can be implemented in various forms and should not be interpreted as being limited to the embodiments presented herein. Rather, these embodiments are provided so that the disclosure will be thorough and complete and will fully convey the scope of the present application to those skilled in the art. In the drawings, the sizes and relative sizes of layers and regions can be exaggerated for clarity. Like reference numerals indicate like elements throughout the drawings.

[0029] It should be understood that when an element or layer is referred to as being "on", "adjacent", "connected to", or "coupled to" another element or layer, it can be directly on, adjacent, connected or coupled to the other element or layer, or one or more intervening elements or layers can be present. In contrast, when an element is referred to as being "directly on", "directly adjacent", "directly connected to", or "directly coupled to" another element or layer, then there are no intervening elements or layers present. It will be appreciated that, although terms such as first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are simply used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, terms first, second, third, etc. discussed below can represent first, second, third, etc. elements, components, regions, layers or sections or second, third, etc. elements, components, regions, layers or sections with respect to the first element, component, region, layer or section discussed above.

[0030] Spatially relative terms, such as "beneath", "below", "lower", "under", "above", "upper" and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0031] The terminology used herein is for purposes of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0032] For a thorough understanding of the present application, reference will be made to the following detailed description, in conjunction with the accompanying drawings, in which:

[0033] The embodiment provides a discharge control circuit 21 applied in a battery management chip 2. Exemplarily, the battery management chip 2 can be a charge and discharge management chip. The battery management chip 2 further comprises a charge control circuit 22; the charge control circuit 22 is used for connecting the battery 1 and a load connection end, and is used for performing charge control on the battery 1. As an example, during a charge operation, a charger is connected to the load connection end, and the battery 1 is charged through the charge control circuit 22. When the load connection end is floating or is not connected to the charger, the battery 1 modulates an output voltage of the load connection end to a preset output voltage, for example, 1.5V, to simulate a dry battery to perform discharge. Wherein, the battery 1 can be a lithium battery.

[0034] The embodiment provides a discharge control circuit 21, comprising a first voltage conversion module 211, a load detection module 212 and a second voltage conversion module 213; the first voltage conversion module 211 is used for connecting the battery 1 and the load connection end, and is used for providing a first output voltage to the load connection end; the load detection module 212 is connected with the first voltage conversion module 211 and the second voltage conversion module 213, and is used for driving the first voltage conversion module 211 to enter a non-working state and driving the second voltage conversion module 213 to enter a working state when a load current output by the load connection end is less than a preset current threshold; the second voltage conversion module 213 is connected with the first voltage conversion module 211, is used for connecting the battery 1 and the load connection end, and is used for providing a target voltage to the load connection end and driving the first voltage conversion module 211 to enter the working state when a load device is connected to the load connection end.

[0035] The first voltage conversion module 211 and the second voltage conversion module 213 are both used for converting the battery voltage output by the battery 1, and outputting a discharge voltage used for simulating the discharge of a dry battery, for example, 1.5V. The power consumption of the first voltage conversion module 211 and the second voltage conversion module 213 is different. The power consumption of the first voltage conversion module 211 is greater than that of the second voltage conversion module 213. Therefore, when the load is empty, the discharge is performed through the second voltage conversion module 213 to reduce the static power consumption. When the load is full, the discharge is performed through the first voltage conversion module 211 to meet the large-current discharge requirement.

[0036] As an example, the first voltage conversion module 211 is connected to the battery 1 and the load connection end, and is used for providing a first output voltage to the load connection end. In this example, the first voltage conversion module 211 performs discharge work based on the battery 1 as a power supply.

[0037] As an example, the load detection module 212 is connected to the first voltage conversion module 211 and the second voltage conversion module 213, and is used for driving the first voltage conversion module 211 to enter a non-working state and driving the second voltage conversion module 213 to enter a working state when the load current output by the load connection end is less than a preset current threshold. The preset current threshold is a preset current threshold used for judging whether the load is empty, which can be set according to actual experience and is not limited herein. In this example, when the load current output by the load connection end is less than the preset current threshold, the load detection module 212 determines that the load connection end is empty at this time, drives the first voltage conversion module 211 to enter a non-working state, and drives the second voltage conversion module 213 to enter a working state to reduce the static power consumption.

[0038] As an example, the second voltage conversion module 213 is connected to the first voltage conversion module 211, and is used for connecting the battery 1 and the load connection end, and is used for providing a target voltage to the load connection end when the load device is connected to the load connection end, and driving the first voltage conversion module 211 to enter a working state. In this example, the second voltage conversion module 213 can detect the measured voltage of the load connection end to determine whether the load device is connected to the load connection end. When the load device is connected to the load connection end, the discharge work is performed based on the battery 1 as a power supply, and the target voltage is provided to the load connection end. Since the discharge voltage will decrease when the load connection end is connected from empty to the load device, the target voltage is used to maintain the discharge voltage of the load connection end to prevent the discharge voltage from falling, and the first voltage conversion module 211 is driven to enter a working state to meet the large-current discharge requirement through the first voltage conversion module 211.

[0039] In the embodiment, the discharge control circuit 21 comprises a first voltage conversion module 211, a load detection module 212 and a second voltage conversion module 213; the first voltage conversion module 211 is connected with the battery 1 and the load connection end, and is configured to provide a first output voltage to the load connection end; the load detection module 212 is connected with the first voltage conversion module 211 and the second voltage conversion module 213, and is configured to drive the first voltage conversion module 211 into a non-working state and drive the second voltage conversion module 213 into a working state when a load current output by the load connection end is less than a preset current threshold; the second voltage conversion module 213 is connected with the first voltage conversion module 211, and is configured to connect the battery 1 and the load connection end, and provide a target voltage to the load connection end when a load device is connected to the load connection end, and drive the first voltage conversion module 211 into a working state, so that the second voltage conversion module 213 provides a target voltage to compensate for a discharge voltage of the load connection end when the load device is connected to the load connection end, prevents the discharge voltage from falling, and drives the first voltage conversion module 211 into a working state to meet a large-current discharge requirement through the first voltage conversion module 211, thereby preventing the discharge voltage from falling when the load device is connected to the load connection end while ensuring low power consumption.

[0040] In an embodiment, the second voltage conversion module 213 comprises a voltage comparison module 2131 and a logic output module 2132; the voltage comparison module 2131 is connected with the load detection module 212, the load connection end and the first voltage conversion module 211, and is configured to output a first comparison signal when a measured voltage output by the load connection end is less than a first voltage threshold, and output a second comparison signal when the measured voltage is less than a second voltage threshold; the second voltage threshold is less than the first voltage threshold; the second comparison signal is configured to drive the second voltage conversion module 213 into a working state; and the logic output module 2132 is connected with the voltage comparison module 2131 and the load connection end, and is configured to provide the target voltage to the load connection end according to the first comparison signal or the second comparison signal.

[0041] The first voltage threshold and the second voltage threshold can be configured according to actual requirements, and are not limited herein. It is only required that the second voltage threshold be less than the first voltage threshold.

[0042] As an example, when the measured voltage outputted by the load connection end is less than the first voltage threshold, the voltage comparison module 2131 outputs a first comparison signal, through which the logic output module 2132 provides a smaller target voltage to the load connection end. If the measured voltage does not increase but continues to decrease, when the measured voltage is less than the second voltage threshold, the voltage comparison module 2131 outputs a second comparison signal, through which the logic output module 2132 provides a larger target voltage to the load connection end and drives the second voltage conversion module 213 into a working state through the second comparison signal. It can be understood that, since the measured voltage, i.e., the discharge voltage, will decrease when the load connection end is connected to a load device, the first voltage threshold and the second voltage threshold are used to determine the decrease amplitude of the measured voltage, so as to determine whether the load connection end is connected to a load device. When the load connection end is connected to a load device, the target voltage is provided to the load connection end to prevent the measured voltage from falling, and the second voltage conversion module 213 is driven into a working state to ensure the large-current discharge requirement. Exemplarily, the logic output module 2132 includes an LDO (Low Dropout Regulator, low dropout regulator, LDO for short) module.

[0043] In an embodiment, the difference between the second voltage threshold and the first voltage threshold ranges from 95 millivolts to 105 millivolts. Preferably, the difference between the second voltage threshold and the first voltage threshold is 100 millivolts. In this example, the difference between the second voltage threshold and the first voltage threshold can be used to determine the decrease amplitude of the measured voltage, so as to determine whether the load connection end is connected to a load device.

[0044] In an embodiment, the second voltage conversion module 213 further includes a reference voltage module 2133 connected to the voltage comparison module 2131, configured to provide a first reference voltage corresponding to the first voltage threshold and a second reference voltage corresponding to the second voltage threshold to the voltage comparison module 2131.

[0045] In this embodiment, the reference voltage module 2133 can adopt a low-power voltage module, for example, 100 nA, to reduce the overall power consumption of the discharge control circuit 21.

[0046] In this embodiment, the second voltage conversion module 213 further includes a reference voltage module 2133 connected to the voltage comparison module 2131, configured to provide a first reference voltage corresponding to the first voltage threshold and a second reference voltage corresponding to the second voltage threshold to the voltage comparison module 2131. Thus, the first reference voltage corresponding to the first voltage threshold and the second reference voltage corresponding to the second voltage threshold are simultaneously provided by one reference voltage module 2133, reducing the volume and cost.

[0047] In an embodiment, the voltage comparison module 2131 comprises a first comparator 213a and a second comparator 213b; the first input terminal of the first comparator 213a is connected with the reference voltage module 2133, the second input terminal of the first comparator 213a is connected with the load connection terminal, the enable terminal of the first comparator 213a is connected with the load detection module 212, the output terminal of the first comparator 213a is connected with the logic output module 2132; the first input terminal of the second comparator 213b is connected with the reference voltage module 2133, the second input terminal of the second comparator 213b is connected with the load connection terminal, the enable terminal of the second comparator 213b is connected with the output terminal of the first comparator 213a, the output terminal of the second comparator 213b is connected with the logic output module 2132 and the first voltage conversion module 211.

[0048] In the embodiment, the first comparator 213a is a low-power comparator, and the second comparator 213b is a high-speed comparator. The power consumption of the first comparator 213a is greater than that of the second comparator 213b. In the embodiment, the second comparator 213b is enabled only when the first comparator 213a outputs the first comparison signal, and the enable time of the second comparator 213b is short, so the power consumption of the second comparator 213b can be ignored.

[0049] As an example, when the first comparator 213a detects that the measured voltage is less than the first reference voltage, a high-level signal is outputted, the second comparator 213b is enabled, and the logic output module 2132 is instructed to supplement energy for the measured voltage in a small range, so as to force the measured voltage to rise. At this time, the second comparator 213b is enabled, and when the logic output module 2132 supplements energy for the measured voltage in a small range, if the measured voltage does not rise, but is less than the second reference voltage, the second comparator 213b outputs a high-level signal, the first voltage conversion module 211 is enabled to enter a working state, and the logic output module 2132 is instructed to supplement energy for the measured voltage in a large range, so as to force the measured voltage to rise, thereby preventing the situation that the discharge voltage drops when the load device is connected.

[0050] In the embodiment, the voltage comparison module 2131 includes a first comparator 213a and a second comparator 213b; the first input end of the first comparator 213a is connected with the reference voltage module 2133, the second input end of the first comparator 213a is connected with the load connection end, the enable end of the first comparator 213a is connected with the load detection module 212, the output end of the first comparator 213a is connected with the logic output module 2132; the first input end of the second comparator 213b is connected with the reference voltage module 2133, the second input end of the second comparator 213b is connected with the load connection end, the enable end of the second comparator 213b is connected with the output end of the first comparator 213a, the output end of the second comparator 213b is connected with the logic output module 2132 and the first voltage conversion module 211, so as to determine whether the load connection end is connected with the load device by using the first comparator 213a and the second comparator 213b, when the load connection end is connected with the load device, the logic output module 2132 is instructed to output the target voltage to supplement the discharge voltage and prevent the discharge voltage from falling, and the first voltage conversion module 211 is driven to enter the working state to meet the large-current discharge requirement.

[0051] In an embodiment, the first voltage conversion module 211 includes a Buck module; the second voltage conversion module includes an LDO module. As an example, the first voltage conversion module 211 includes the Buck module to improve the discharge efficiency and meet the large-current discharge requirement. As an example, the second voltage conversion module 213 includes the LDO module, specifically, the logic output module 2132 in the above embodiment includes the LDO module, when the load connection end is connected with the load device, the stable target voltage is provided to the load connection end, and the first voltage conversion module 211 is driven to enter the working state. When the load connection end is not connected with the load device, the standby power consumption is reduced.

[0052] The embodiment provides a battery management chip 2 including the discharge control circuit 21.

[0053] In an embodiment, the battery management chip 2 further includes a charging control circuit 22; the charging control circuit 22 is used for connecting the battery 1 and the load connection end, and is used for charging control of the battery 1.

[0054] The embodiment provides a battery management system including the battery 1 and the battery management chip 2.

[0055] The embodiment provides a battery module including the battery management system.

[0056] The above-described embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A discharge control circuit, characterized in that, It includes a first voltage conversion module, a load detection module, and a second voltage conversion module; The first voltage conversion module is used to connect the battery and the load connection terminal, and is used to provide a first output voltage to the load connection terminal; The load detection module is connected to the first voltage conversion module and the second voltage conversion module. When the load current output at the load connection terminal is less than a preset current threshold, it drives the first voltage conversion module to enter a non-working state and drives the second voltage conversion module to enter a working state. The second voltage conversion module is connected to the first voltage conversion module and is used to connect the battery and the load connection terminal. When a load device is connected to the load connection terminal, the second voltage conversion module provides a target voltage to the load connection terminal and drives the first voltage conversion module to enter the working state.

2. The discharge control circuit as described in claim 1, characterized in that, The second voltage conversion module includes a voltage comparison module and a logic output module; The voltage comparison module is connected to the load detection module, the load connection terminal, and the first voltage conversion module. It is used to output a first comparison signal when the measured voltage output at the load connection terminal is less than a first voltage threshold; and to output a second comparison signal when the measured voltage is less than a second voltage threshold. The second voltage threshold is less than the first voltage threshold. The second comparison signal is used to drive the second voltage conversion module to enter the working state. The logic output module is connected to the voltage comparison module and the load connection terminal, and is used to provide a target voltage to the load connection terminal according to the first comparison signal or the second comparison signal.

3. The discharge control circuit as described in claim 2, characterized in that, The difference between the second voltage threshold and the first voltage threshold ranges from 95 millivolts to 105 millivolts.

4. The discharge control circuit as described in claim 2, characterized in that, The second voltage conversion module further includes a reference voltage module, which is connected to the voltage comparison module and is used to provide a first reference voltage corresponding to the first voltage threshold and a second reference voltage corresponding to the second voltage threshold to the voltage comparison module.

5. The discharge control circuit as described in claim 4, characterized in that, The voltage comparison module includes a first comparator and a second comparator; The first input terminal of the first comparator is connected to the reference voltage module, the second input terminal of the first comparator is connected to the load connection terminal, the enable terminal of the first comparator is connected to the load detection module, and the output terminal of the first comparator is connected to the logic output module. The first input terminal of the second comparator is connected to the reference voltage module, the second input terminal of the second comparator is connected to the load connection terminal, the enable terminal of the second comparator is connected to the output terminal of the first comparator, and the output terminal of the second comparator is connected to the logic output module and the first voltage conversion module.

6. The discharge control circuit as described in claim 1, characterized in that, The first voltage conversion module includes a Buck module; the second voltage conversion module includes an LDO module.

7. A battery management chip, characterized in that, Includes the discharge control circuit as described in any one of claims 1 to 6.

8. The battery management chip as described in claim 7, characterized in that, The battery management chip also includes a charging control circuit; the charging control circuit is used to connect the battery and the load connection terminal, and is used to control the charging of the battery.

9. A battery management system, characterized in that, It includes a battery and a battery management chip as described in claim 7 or 8; the battery is connected to the battery management chip.

10. A battery module, characterized in that, Includes the battery management system as described in claim 9.

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