Battery protection power-up circuit with out-of-order installation

Abstract

The application discloses a power-on circuit for protecting battery disorderly installation. The power-on circuit is formed with a plurality of series battery installation positions, the battery installation positions are used for installing batteries, a plurality of batteries are connected in series to form a battery pack, and the power-on circuit comprises a protection chip. The protection chip comprises a voltage division group and a power-on starting module. The voltage division group comprises a plurality of voltage division resistors. The voltage division resistors are connected in series in sequence, and one voltage division resistor corresponds to one battery installation position in parallel. The power-on starting module comprises a switch tube and a protection resistor. The first end of the switch tube is connected with the voltage division group. The second end of the switch tube is connected with one end of the protection resistor. The other end of the protection resistor is grounded. The control end of the switch tube is connected with a control line. The internal resistance of the battery is defined as R, the voltage division resistor is defined as Rn, and the protection resistor is defined as R0. R<<R0<<Rn is met. The technical scheme of the application can effectively reduce the situation that the protection IC triggers the MOS switch to flip, and abnormal protection behaviors are reduced.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of battery protection, and particularly relates to an upper power supply circuit for protecting battery disorderly installation. BACKGROUND

[0002] At present, a protection IC (Integrated Circuit) has a limited condition for upper power supply of each battery of a lithium battery. For example, manual welding or mechanical hand welding always has a condition of asynchronization or random sequence. If the asynchronization time exceeds the waiting time of the protection IC, the protection IC has a probability of triggering a MOS switch to flip, resulting in fuse blowout and abnormal protection behavior. SUMMARY

[0003] In view of the defects in the prior art, the application provides an upper power supply circuit for protecting battery disorderly installation, which can effectively reduce the condition of triggering the MOS switch to flip by the protection IC and reduce abnormal protection behavior.

[0004] The application provides an upper power supply circuit for protecting battery disorderly installation, wherein the upper power supply circuit is formed with a plurality of battery installation positions in series, the battery installation positions are used for installing batteries, a plurality of batteries are connected in series to form a battery pack, and the upper power supply circuit comprises a protection chip.

[0005] A voltage division group, wherein the voltage division group comprises a plurality of voltage division resistors, the voltage division resistors are connected in series in sequence, and one voltage division resistor corresponds to one battery installation position in parallel;

[0006] An upper power supply starting module, wherein the upper power supply starting module comprises a switch tube and a protection resistor, a first end of the switch tube is connected to the voltage division group, a second end of the switch tube is connected to one end of the protection resistor, the other end of the protection resistor is grounded, and a control end of the switch tube is connected to a control line;

[0007] The internal resistance of the battery is defined as R, the voltage division resistor is defined as Rn, and the protection resistor is defined as R0, and R<<R0<<Rn is met.

[0008] In one aspect, R0=400k Ω , and Rn=40M Ω .

[0009] In one aspect, the upper power supply circuit comprises a connecting resistor, one end of the connecting resistor is connected to the voltage division group, and the other end of the connecting resistor is connected to the first end of the switch tube.

[0010] In one aspect, the switch tube is a MOS tube, the first end of the switch tube is a drain, the second end is a source, and the control end is a gate.

[0011] In one aspect, the switch tube is an NPN type MOS tube.

[0012] In one aspect, the voltage divider group includes a first voltage divider resistor, a second voltage divider resistor, a third voltage divider resistor, and a fourth voltage divider resistor, with the first voltage divider resistor defined as R1, the second voltage divider resistor defined as R2, the third voltage divider resistor defined as R3, and the fourth voltage divider resistor defined as R4, and R1 = R2 = R3 = R4 is satisfied.

[0013] The beneficial effects of the present application are embodied in that if one of the battery mounting positions is not installed with a battery, the battery pack is equivalent to a voltage source with a large internal resistance. Since the protection resistor is much smaller than the voltage divider resistor, in this case the voltage source equivalent to the battery pack remains at a low level, the first end of the switch tube is at a low level, and the control line cannot normally be flipped high. In this way, the protection chip cannot be normally powered on. When all the battery mounting positions are loaded with batteries, the voltage source equivalent to the battery pack can normally be raised, the control line can also be flipped high, the first end of the switch tube is at a high level, and the switch tube is turned off. The protection chip power-on starting circuit is closed, and no longer consumes power consumption. The technical solution of the present application can effectively reduce the situation of triggering the switch tube to flip by the protection chip, and reduce abnormal protection behavior. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual proportions.

[0015] Figure 1 A schematic diagram of the power-on circuit for protecting the battery installation disorder of the present application;

[0016] Figure 2 A schematic diagram of the equivalent circuit in the power-on circuit for protecting the battery installation disorder of the present application.

[0017] BRIEF DESCRIPTION OF DRAWINGS: 10, battery mounting position; 20, protection chip; 210, voltage divider group; 220, power-on starting module;

[0018] R*, connection resistor; VDD, power supply end; PM0, switch tube. DETAILED DESCRIPTION

[0019] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0020] It should be noted that the technical terms or scientific terms used in the present application should be understood as the general meanings understood by the skilled in the art, unless otherwise specified.

[0021] Referring to Figure 1 As shown in the drawings, the present application provides a power-on circuit for protecting disordered battery installation, the power-on circuit is formed with a plurality of battery installation positions 10 connected in series, the battery installation positions 10 are used for installing batteries, and the plurality of batteries are connected in series to form a battery pack. The power-on circuit comprises a protection chip 20, and the protection chip 20 comprises a voltage division group 210 and a power-on starting module 220.

[0022] The voltage division group 210 comprises a plurality of voltage division resistors connected in series, and one voltage division resistor corresponds to one battery installation position 10 connected in parallel; the power-on starting module 220 comprises a switch tube PM0 and a protection resistor, a first end of the switch tube PM0 is connected to the voltage division group 210, a second end of the switch tube PM0 is connected to one end of the protection resistor, the other end of the protection resistor is grounded, and a control end of the switch tube PM0 is connected to a control line; the internal resistance of the battery is defined as R, the voltage division resistor is defined as Rn, and the protection resistor is defined as R0, and R << R0 << Rn is satisfied. Therefore, the internal resistance of the battery is much smaller than the protection resistor, and the protection resistor is much smaller than the voltage division resistor.

[0023] In the embodiment, if one of the battery installation positions 10 is not installed with a battery, the battery pack is equivalent to a voltage source with a large internal resistance. Since the protection resistor is much smaller than the voltage division resistor, the voltage source equivalent to the battery pack remains at a low level in this case, the first end of the switch tube PM0 is at a low level, and the control line cannot be normally flipped high. In this way, the protection chip 20 cannot be normally powered on. When all the battery installation positions 10 are loaded with batteries, the voltage source equivalent to the battery pack can be normally raised, the control line can be flipped high, the first end of the switch tube PM0 is at a high level, and the switch tube PM0 is turned off. The power-on starting circuit of the protection chip 20 is closed, and no longer consumes power consumption. The technical solution of the present application can effectively reduce the situation of triggering the switch tube PM0 to flip by the protection chip 20, and reduce abnormal protection behavior.

[0024] In an embodiment of the present application, R0 = 400k Ω , Rn = 40M Ω . The protection resistor is ensured to be much smaller than the voltage division resistor.

[0025] In an embodiment of the present application, the power-on circuit comprises a connecting resistor R*, one end of the connecting resistor R* is connected to the voltage division group 210, and the other end of the connecting resistor R* is connected to the first end of the switch tube PM0. The connecting resistor R* is used for protecting the battery pack.

[0026] In an embodiment of the present application, the switch tube PM0 is a MOS tube, the first end of the switch tube PM0 is a drain, the second end is a source, and the control end is a gate. The MOS tube is a MOS field effect tube, also known as a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). It generally has two types of depletion mode and enhancement mode. The enhancement mode MOS field effect tube can be divided into NPN type and PNP type. The NPN type is usually referred to as N-channel type, and the PNP type is also called P-channel type. For the N-channel field effect tube, the source and the drain are connected to the N-type semiconductor, and similarly for the P-channel field effect tube, the source and the drain are connected to the P-type semiconductor. The output current of the field effect tube is controlled by the input voltage (or electric field), and the input current is extremely small or even zero, which makes the device have a very high input impedance, and this is also the reason why we call it a field effect tube.

[0027] Further, the switch tube PM0 is an NPN type MOS tube. The switch tube PM0 is turned off at a high level and turned on at a low level.

[0028] In an embodiment of the present application, the voltage dividing group 210 includes a first voltage dividing resistor, a second voltage dividing resistor, a third voltage dividing resistor, and a fourth voltage dividing resistor, the first voltage dividing resistor is defined as R1, the second voltage dividing resistor is defined as R2, the third voltage dividing resistor is defined as R3, and the fourth voltage dividing resistor is defined as R4, and R1=R2=R3=R4 is satisfied. R1, R2, R3, and R4 are equal, and can each be 40MΩ. The positive pole of each battery is connected to a corresponding resistor node, and the negative pole is grounded. The voltage dividing resistor is generally selected to be a resistor with high voltage resistance and high unit resistance, usually with a tolerance of ≤1% and a rated power of ≥0.25W, to ensure long-term stable operation in a high voltage environment, and to reduce the area and save space.

[0029] Referring to Figure 2As shown, when the first voltage dividing resistor corresponds to the battery mounting position 10 without installing the battery, and the second voltage dividing resistor, the third voltage dividing resistor and the fourth voltage dividing resistor correspond to the battery mounting position 10 with installing the battery, the first voltage dividing resistor corresponds to the battery mounting position 10 is disconnected, and the current passes through the second voltage dividing resistor, the third voltage dividing resistor and the fourth voltage dividing resistor corresponding to the battery mounting position 10. From the power supply end VDD, the battery pack is equivalent to a voltage source with an internal resistance greater than 40 Mohm, and the internal resistance of the battery can be ignored. The voltage of the power supply end VDD is the voltage drop of the battery pack on the internal resistance and the protection resistor: VDD=(VC2+VC3+VC4)*R0 / R1, VC2 is the voltage corresponding to the second voltage dividing resistor, VC3 is the voltage corresponding to the third voltage dividing resistor, and VC4 is the voltage corresponding to the fourth voltage dividing resistor. Since the protection resistor is much smaller than the voltage dividing resistor, in this case, the power supply end VDD remains low, the control line PORN cannot normally flip high, the initial value of the control line PORN is low by default, and the protection chip 20 cannot normally power on. When all the batteries are successfully loaded, the power supply end VDD can normally rise, the control line PORN also rises, the switch tube PM0 is turned off, the power-on starting circuit is closed, and no power consumption is consumed.

[0030] Finally, it should be noted that: the above 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 or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.

Claims

1. A power-up circuit to protect battery out-of-order installation, characterized by, The power-on circuit is formed with a plurality of series battery mounting positions for mounting batteries, a plurality of batteries are connected in series to form a battery pack, and the power-on circuit comprises a protection chip, which comprises: a voltage division group comprising a plurality of voltage division resistors connected in series, and one voltage division resistor corresponding to one battery mounting position in parallel; a power-on starting module comprising a switch tube and a protection resistor, a first end of the switch tube being connected to the voltage division group, a second end of the switch tube being connected to one end of the protection resistor, the other end of the protection resistor being grounded, and a control end of the switch tube being connected to a control line; The internal resistance of the battery is defined as R, the partial pressure resistance is Rn, and the protection resistance is R0, and the following is satisfied: ; the power-on circuit comprises a connecting resistor, one end of the connecting resistor being connected to the voltage division group, and the other end of the connecting resistor being connected to the first end of the switch tube.

2. The power-on circuit of claim 1, wherein, R0=400kΩ, Rn=40MΩ.

3. The power-on circuit of claim 1, wherein, The switch tube is a MOS tube, the first end of the switch tube is a drain, the second end is a source, and the control end is a gate.

4. The power circuit to protect battery out-of-order installation according to claim 3, characterized in that, The switch tube is an NPN type MOS tube.

5. The power circuit to protect battery out-of-order installation of claim 1, wherein, The voltage division group comprises a first voltage division resistor, a second voltage division resistor, a third voltage division resistor, and a fourth voltage division resistor, the first voltage division resistor is defined as R1, the second voltage division resistor is defined as R2, the third voltage division resistor is defined as R3, and the fourth voltage division resistor is defined as R4, and R1=R2=R3=R4 is satisfied.

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