WO2017219491A1

WO2017219491A1 - Battery voltage protection circuit

Info

Publication number: WO2017219491A1
Application number: PCT/CN2016/097333
Authority: WO
Inventors: 朱智会; 张万春
Original assignee: 广东森维绿联科技有限公司
Priority date: 2016-06-24
Filing date: 2016-08-30
Publication date: 2017-12-28
Also published as: CN206023261U

Abstract

A battery voltage protection circuit. When a battery voltage reaches two interval voltages of a voltage determination unit, a corresponding voltage determination is made, and a low-voltage determination switch (V1), a high-voltage determination switch (V2), and a transistor (Q2) make a switch-off or switch-on operation to protect the battery from falling into a weak discharge region.

Description

Battery voltage protection circuit

Technical field

The utility model relates to a battery voltage protection circuit, in particular to a built-in battery voltage protection circuit of a portable low power consumption product.

Background technique

With the refinement of portable device products, the development of batteries has also evolved, and the operating voltages during the use of electronic products vary. If the battery is lower than the operating voltage of the electronic device, it is difficult for the device to continue to work. If the battery voltage is higher than the device, the device will be unstable. How to balance the working voltage of the battery is an urgent problem to be solved in current portable electronic products.

Summary of the invention

The technical problem to be solved by the utility model is to overcome the above technical problems and provide a battery balancing circuit with high reliability.

The technical solution of the present invention provides a battery voltage protection circuit including a voltage output terminal VOUT, a voltage input terminal VIN, and a battery voltage determining unit. The battery voltage determining unit includes a low voltage determination switch V1, a high voltage determination switch V2, and a triode. Q2, when the battery voltage reaches the first voltage interval, the high voltage determination switch V1 and the low voltage determination switch V2 are turned on, Q2 is turned on, and VOUT is the battery voltage; when the battery voltage is lower than the first voltage interval and higher than the second voltage interval, The low voltage determination switch V1 is turned on, the high voltage determination switch V2 is turned off, Q2 is turned on, and VOUT is the battery voltage; when the battery voltage is lower than the low voltage determination value, the low voltage determination switch V1 and the high voltage determination switch V2 are turned off, V1 is turned off, and the battery enters the charging stage. When the battery voltage returns to the high voltage determination value, VOUT is the battery voltage.

The V1 and V2 are NPN type transistors, which are flow control type originals, and the transistor Q2 is a field effect transistor.

The current flowing through the C poles of V1 and V2 is multiplied by the current of the B pole.

The V1 and V2 are respectively provided with a bias circuit.

The B pole current of the V1 and V2 is one tenth of the bias circuit.

The utility model also provides a battery voltage protection circuit, comprising a voltage output terminal VOUT and a voltage input terminal VIN, characterized in that it further comprises a triode Q2, filter capacitors C9, C10, C11, resistors R10, R13, R14, R15, R16. , NPN type transistors V1, V2, the gate of the transistor Q2, one end of the resistors R10, R14, the capacitors C10, C11 One end is connected to VIN; the source of the transistor Q2, one end of the capacitor C9, and one end of the resistor R13 are connected to VOUT; the base of the NPN transistor V1, V2 and the drain of Q2, one end of the capacitor C10, and the resistor R10 One end of the NPN-type transistor V1 is connected to one end of the resistors R13 and R15; the collector of the NPN-type transistor V2 is connected to one end of the resistors R14 and R16; and the emitter of the NPN-type transistor V1 and V2 is One ends of the capacitors C9 and C11 and one ends of the resistors R15 and R16 are connected to the ground.

The capacitors C9 and C11 are filter capacitors.

The capacitor C10 is used to avoid the conduction and current changes of Q2 when the battery voltage is shaken.

The value of the resistor R10 is 100k, and the Q2 conduction speed can be adjusted.

The specific advantages of the utility model are as follows: 1. Fully protect the battery, prevent the battery from sinking into a weak discharge area, and provide a strong power region for the subsequent load. 2. Using discrete components, the conduction current can be well adjusted. When different loads are used, different field effect transistors can be replaced, and the protection voltage range requirements can be adjusted accordingly. 3, the use of discrete components, maintenance needs to pay a small price.

The above summary and the following detailed description are intended to be illustrative of the scope of the claims Other objects and advantages of the present invention will be described in the following description and the accompanying drawings.

DRAWINGS

1 is a circuit diagram of a battery voltage determining unit according to an embodiment of the invention

[Main components and reference marks]

Effect transistor Q2

NPN type transistor V1, V2

Capacitor C9~C11

Resistance R10, R13～R16

Bias current i1, i2

Current lc1, lc2

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG. 1 , the utility model relates to a battery voltage protection circuit, which comprises a voltage output terminal VOUT and a voltage input terminal VIN, which is characterized in that it further comprises a triode Q2, a filter capacitor C9, C10, C11, a resistor R10, R13, R14, R15, R16, NPN type transistors V1, V2, the gate of the transistor Q2, one end of the resistors R10, R14, one end of the capacitor C10, C11 are connected to the VIN; the source of the transistor Q2, the capacitor C9 One end, resistor R13 One end is connected to VOUT; the base of the NPN-type transistors V1 and V2 is connected to the drain of Q2, one end of the capacitor C10, and one end of the resistor R10; the collector of the NPN-type transistor V1 is connected to one end of the resistors R13 and R15; The collector of the NPN transistor V2 is connected to one end of the resistors R14 and R16; the emitter of the NPN transistor V1, V2, one end of the capacitors C9 and C11, and one end of the resistors R15 and R16 are connected to the ground.

V1 and V2 are battery voltage determination switches, V2 is a high voltage determination switch, and V1 is a low voltage determination switch. When the battery voltage reaches the first voltage zone value of 4.2v, V2 is turned on, and V2 is extremely low, Q2 Pass, V1 is turned on. VOUT is the lithium battery voltage. When the battery voltage is gradually discharged, the battery voltage is lower than the first voltage zone value of 4.2v, but V1 is turned on when the second voltage zone value is 3.2v, V2 is turned off, Q2 is turned on, and VOUT is still the battery voltage. When the battery voltage is lower than the second voltage zone value of 3.2v, V1, V2, and Q2 are cut off. At this time, the battery VIN can no longer supply power to the subsequent load, only charging, when the battery voltage returns to the first voltage zone value 4.2v again. VOUT continues to provide power for subsequent loads.

The V1 and V2 are NPN type triodes, which are flow control type originals. The current flowing through the C poles of V1 and V2 is multiplied by the current of the B pole, usually between 40 and 80 times, and the B pole of V1 and V2. The current is typically one tenth of the bias circuit. I1 is the bias current of V1, and i2 is the bias current of V2. Therefore, if there is a constraint condition Ic1=φ*i1 and Ic2=φ*i2, the value of R10 cannot be fetched. Select 100k, which is related to the bias circuit we set. Another function of R10 can adjust the speed of Q2 conduction.

Among them, 17, C11 is the filter capacitor, because the battery is powered, the voltage ripple is relatively small, as long as the withstand voltage range of the two is in the VIN range.

The purpose of C10 is to avoid the conduction and current changes of Q2 when the battery voltage is shaken.

The foregoing is merely illustrative of the preferred embodiments of the invention, and is not to be construed as limiting The present invention is not limited to the above embodiments, and the specific structure thereof is allowed to vary, but various changes and modifications made within the scope of the independent claims of the present invention are within the scope of protection.

Claims

A battery voltage protection circuit for protecting voltage stability of a circuit, comprising a voltage output terminal VOUT and a voltage input terminal VIN, characterized in that:

A battery voltage determining unit includes a low voltage determining switch V1, a high voltage determining switch V2 and a triode Q2. When the battery voltage reaches the first voltage interval, the high voltage determining switch V1 and the low voltage determining switch V2 are turned on, Q2 is turned on, and VOUT is the battery voltage. ;

When the battery voltage is lower than the first voltage interval and higher than the second voltage interval, the low voltage determination switch V1 is turned on, the high voltage determination switch V2 is turned off, Q2 is turned on, and VOUT is the battery voltage;

When the battery voltage is lower than the first voltage interval determination value, the low voltage determination switch V1 and the high voltage determination switch V2 are turned off, V1 is turned off, the battery enters the charging phase, and when the battery voltage returns to the second voltage interval determination value, VOUT is the battery voltage.
The battery voltage protection circuit according to claim 1, wherein the V1 and V2 are NPN type transistors, which are flow control type originals.
A battery voltage protection circuit according to claim 1, wherein said transistor Q2 is a field effect transistor.
A battery voltage protection circuit according to claim 1 or 2, wherein the current flowing through the C poles of V1 and V2 is multiplied by the current of the B pole.
A battery voltage protection circuit according to claim 1, wherein said V1 and V2 are respectively provided with bias circuits.
A battery voltage protection circuit according to any one of claims 1, 2 or 5, wherein the B pole current of said V1, V2 is one tenth of a bias circuit.
A battery voltage protection circuit includes a voltage output terminal VOUT and a voltage input terminal VIN, and is characterized in that it further comprises a triode Q2, a filter capacitor C9, C10, C11, a resistor R10, R13, R14, R15, R16, and an NPN type transistor V1. , V2,

The gate of the transistor Q2, one end of the resistors R10 and R14, and one end of the capacitors C10 and C11 are connected to the VIN;

a source of the transistor Q2, one end of the capacitor C9, and one end of the resistor R13 are connected to VOUT;

The bases of the NPN transistors V1, V2 are connected to the drain of Q2, one end of the capacitor C10, and one end of the resistor R10;

The collector of the NPN transistor V1 is connected to one end of the resistors R13 and R15;

The collector of the NPN transistor V2 is connected to one end of the resistors R14 and R16;

The emitters of the NPN transistors V1 and V2, one ends of the capacitors C9 and C11, and one ends of the resistors R15 and R16 are connected to the ground.
The battery voltage protection circuit according to claim 7, wherein the capacitors C9 and C11 are filter capacitors.
A battery voltage protection circuit according to claim 7, wherein said resistor R10 has a value of 100k.