CN107290670A - Power display circuit and its control method, lamp - Google Patents

Abstract

The invention relates to an electric quantity display circuit, which comprises a power supply input end, a power supply output end and a power supply output end, wherein the power supply input end is connected with a battery to receive power supply of the battery; the electric quantity display circuit also comprises a switch circuit, a control circuit, a voltage stabilizing circuit, a voltage detection circuit, a backlight circuit, a display circuit and a reference circuit; the switching circuit is used for overturning the level of the trigger end to form a trigger signal; the control circuit performs mode switching under the control of the trigger signal; the voltage stabilizing circuit is respectively connected with the power input end and the control circuit; the voltage detection circuit is respectively connected with the power input end and the control circuit; the control circuit is also used for supplying power to the backlight circuit, the display circuit and the reference circuit and controlling the backlight circuit, the display circuit and the reference circuit to work in the working mode. The electric quantity display circuit has the advantages of low power consumption and low leakage current. The invention relates to a control method of a circuit display circuit and a lamp.

Description

Power display circuit and its control method, lamp

technical field

The invention relates to the technical field of power display, in particular to a power display circuit and a control method thereof, and also to a lamp.

Background technique

In order to meet the needs of users for knowing the battery power of lamps, more and more portable handheld lamps and mobile lamps using batteries are equipped with power display circuits. Therefore, the user can check the actual power of the lamp as needed, so as to estimate how long the power of the lamp can be used and whether it needs to be charged.

The traditional power display technology can display the remaining power percentage of the lithium battery, and the power display circuit is continuously displayed as the lamp is turned on, resulting in a large waste of electric energy. In order to reduce the waste of electric energy, some lamps will also add an automatic sleep function in the power display circuit. The leakage current of the traditional power display circuit is large during the sleep process, and the power consumption is large, thereby reducing the storage time of the battery.

Contents of the invention

Based on this, it is necessary to provide a power display circuit with low power consumption and low leakage current and its control method, and also provide a lamp.

A power display circuit, including a power input terminal, used to connect with a battery to receive battery power; the power display circuit also includes a switch circuit, a control circuit, a voltage stabilizing circuit, a voltage detection circuit, a backlight circuit, a display circuit and a reference circuit; one end of the switch circuit is respectively connected to the power supply input end and the trigger end of the control circuit, and the other end of the switch circuit is grounded; the switch circuit is used to reverse the level of the trigger end to form trigger signal; the control circuit performs mode switching under the control of the trigger signal, switching from the working mode to the sleep mode or switching from the sleep mode to the working mode, and then controlling the power display circuit to enter the sleep mode or the working mode; The voltage stabilizing circuit is respectively connected with the power supply input terminal and the control circuit; the voltage detection circuit is respectively connected with the power supply input terminal and the control circuit; the control circuit is also respectively connected with the backlight circuit, the The display circuit is connected to the reference circuit; the control circuit is also used to supply power to the backlight circuit, the display circuit and the reference circuit and control the backlight circuit, the display circuit and the reference circuit in the working mode. The above reference circuit works.

In one of the embodiments, the control circuit includes a timer; the timer is used to start timing when the switch circuit triggers the control circuit to enter the working mode; the control circuit is also used to After the timing reaches the preset time, it will switch to sleep mode.

In one of the embodiments, the switch circuit includes a tact switch; the control circuit is also used to receive the level signal input from the trigger terminal and perform multiple consecutive samplings at a preset sampling frequency and then compare multiple sampling results , the control circuit is also used to judge whether the multiple sampling results are the same, and mark the level signal as a trigger signal when the multiple sampling results are the same; in the multiple sampling results at least When it is different once, mark the level signal as a level glitch and end the operation.

In one of the embodiments, the voltage detection circuit includes a first voltage dividing resistor and a second voltage dividing resistor; one end of the first voltage dividing resistor is connected to the input terminal of the power supply, and one end of the first voltage dividing resistor The other end is respectively connected with the second voltage dividing resistor and the control circuit; the other end of the second voltage dividing resistor is grounded.

In one of the embodiments, the preset sampling frequency is 10 ⁵ Hz, and the number of sampling is 5000 times.

In one of the embodiments, the control circuit is a single-chip microcomputer, and the switch circuit also includes a first resistor; the end connected to the trigger terminal of the single-chip microcomputer on the tact switch is also connected to the first resistor through the first resistor. Power input connection.

In one of the embodiments, the reference circuit includes a three-terminal voltage regulator tube and a second resistor; the cathode of the three-terminal voltage regulator tube is connected to the reference electrode and connected to the single-chip microcomputer; After the cathode is connected to the reference electrode, the second resistor is connected in series with the single-chip microcomputer; the anode of the three-terminal voltage regulator tube is grounded.

A lamp includes a battery, a lighting element, and a discharge control circuit; the battery is connected to the lighting element through the discharge control circuit; and a power display circuit as described in any one of the foregoing embodiments.

A method for controlling a power display circuit, used to control the power display circuit as described in any one of the foregoing embodiments, comprising the steps of: receiving a trigger signal from a trigger terminal; controlling the control circuit to switch modes according to the trigger signal, switch from working mode to sleep mode or switch from sleep mode to working mode, and then control the power display circuit to enter sleep mode or working mode; after the control circuit enters working mode, the control circuit sends , the display circuit and the reference circuit supply power and control the backlight circuit, the display circuit and the reference circuit to work.

In one of the embodiments, the step of receiving the trigger signal from the trigger terminal further includes the step of: performing multiple continuous sampling of the level signal input by the trigger terminal at a preset sampling frequency; comparing and judging whether the multiple sampling results are the same ; If yes, mark the level signal as a trigger signal; if not, mark the level signal as a level glitch and end the operation.

In the above power display circuit and its control method, the battery supplies power to the voltage stabilizing circuit through the power input terminal, the voltage stabilizing circuit supplies power to the control circuit, and the backlight circuit, display circuit and reference circuit are powered by the control circuit, and only when the control circuit is in the working mode power supply only. Therefore, when the control circuit is in the sleep mode, the backlight circuit, the display circuit and the reference circuit do not work, and only the voltage stabilizing circuit and the voltage detection circuit work, so that the leakage current in the sleep mode is small and the power consumption is low.

Description of drawings

Fig. 1 is a functional block diagram of a power display circuit in an embodiment;

2A-2B are circuit schematic diagrams of a power display circuit in an embodiment;

FIG. 3 is a flow chart of a control method of the power display circuit in an embodiment.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

1 is a functional block diagram of a power display circuit in an embodiment, the power display circuit includes a power input terminal 110, a switch circuit 120, a control circuit 130, a voltage stabilizing circuit 140, a voltage detection circuit 150, a backlight circuit 160, and a display circuit 170 and reference circuit 180 .

The power input terminal 110 is used for connecting with a battery to receive power from the battery. One end of the switch circuit 120 is respectively connected to the power input end 110 and the trigger end of the control circuit 130, and the other end is grounded, so that when the switch circuit 120 is turned on, the level of the trigger end can be pulled down, and the high level is reversed to a low level. level to form a trigger signal. The voltage stabilizing circuit 140 is connected between the power input terminal 110 and the control circuit 130 . The voltage stabilizing circuit 140 is used for converting the power supply voltage of the power supply input terminal 110 into the working power supply voltage of the control circuit 130 to supply power to the control circuit 130 . The voltage detection circuit 150 is connected to the power input terminal 110 and the control circuit 130 respectively, so as to detect the voltage of the power input terminal 110 and output it to the control circuit 130 to realize the detection of the battery voltage. The control circuit 130 is also connected to the backlight circuit 160 , the display circuit 140 and the reference circuit 180 respectively.

The control circuit 130 performs mode switching under the control of the trigger signal input from the trigger terminal, switching from the current working mode to the sleeping mode or switching from the current sleeping mode to the working mode, and then controls the power display circuit to enter the sleeping mode or the working mode. For example, when the power display circuit is in the working mode, operating the switch circuit 120 will trigger the power display circuit to switch to the sleep mode, and vice versa. After entering the working mode, the control circuit 130 supplies power to the backlight circuit 160 , the display circuit 170 and the reference circuit 180 , and controls the backlight circuit 160 , the display circuit 170 and the reference circuit 180 to work. Specifically, the control circuit 130 compares the voltage value detected by the voltage detection circuit 150 with the voltage in the reference circuit 180 to determine the current battery voltage. The control circuit 130 will also determine the current battery power according to the current battery voltage, and then control the backlight circuit 160 and the display circuit 170 to display the battery power. When the control circuit 130 enters the sleep mode, it does not supply power to the backlight circuit 160 , the display circuit 170 and the reference circuit 180 . Therefore, when the power display circuit is in the sleep mode, only the voltage stabilizing circuit 140 and the voltage detection circuit 150 work, and the backlight circuit 160, the display circuit 170 and the reference circuit 180 do not work, so that the leakage current of the entire circuit in the sleep mode is small , lower power consumption.

In the power display circuit described above, the battery supplies power to the voltage stabilizing circuit 140 through the power input terminal 110, the voltage stabilizing circuit 140 supplies power to the control circuit 130, the backlight circuit 160, the display circuit 170 and the reference circuit 180 are powered by the control circuit 130, and only in the The circuit 130 is powered only when it is in the working mode. Therefore, when the control circuit 130 is in the dormant mode, the backlight circuit 160, the display circuit 170 and the reference circuit 180 do not work, and only the voltage stabilizing circuit 140 and the voltage detection circuit 150 work, so that the leakage current in the dormant mode is small, and the power Low power consumption greatly prolongs battery storage time.

In this embodiment, the control circuit 130 also includes a timer. The timer is used to start timing when the switch circuit 120 triggers the control circuit 130 to enter the working mode. The control circuit 130 is also used to enter the dormant state after the timer counts to a preset duration, thereby avoiding power loss caused by the power display circuit for a long time display, and prolonging the storage time of the battery. In this embodiment, the preset duration is 2 minutes. In other embodiments, the preset duration may also be 0.5-1.5 minutes. The preset duration can be set according to user needs and usage habits.

2A and 2B are schematic circuit diagrams of a power display circuit in an embodiment. Among them, FIG. 2A is a circuit schematic diagram of a voltage stabilizing circuit and a voltage detection circuit in the power display circuit, and FIG. 2B is a circuit schematic diagram of a switch circuit, a control circuit, a backlight circuit, a display circuit, and a reference circuit in the circuit schematic diagram. The power display circuit in this embodiment will be further described in detail below with reference to FIG. 2A and FIG. 2B .

In this embodiment, the control circuit is a single chip microcomputer U1. The voltage stabilizing circuit includes a voltage stabilizing chip U2. The first pin of the voltage stabilizing chip U2 is connected to the power input terminal VIN, connected in series with the capacitor C1, and grounded. The third pin of the voltage stabilizing chip U2 is connected to the eleventh pin of the microcontroller U1, and the third pin of the voltage stabilizing chip U2 is also connected in series with the capacitor C2 and grounded. The voltage stabilizing chip U2 is used to convert the voltage input from the power input terminal VIN into the working voltage VCC of the single-chip microcomputer U1 and then supply power to the single-chip microcomputer U1. The voltage detection circuit includes a first voltage dividing resistor R12, a second voltage dividing resistor R13 and a capacitor C4. Wherein, the first voltage dividing resistor R12 and the second voltage dividing resistor R13 are connected in series between the power input terminal VIN and the ground. The first pin of the microcontroller U1 is connected between the first voltage dividing resistor R12 and the second voltage dividing resistor R13. The capacitor C4 is connected in parallel with the second voltage dividing resistor R13. By adjusting the resistance value between the first voltage dividing resistor R12 and the second voltage dividing resistor R13 and setting the resistance value as large as possible, the leakage current value of the entire power display circuit in sleep mode can be made extremely small. In this embodiment, the resistance values of the first voltage dividing resistor R12 and the second voltage dividing resistor R13 are both 150KΩ, so that the leakage current of the circuit in sleep mode is only 15 μA. It can be understood that, in other embodiments, the resistance values of the first voltage dividing resistor R12 and the second voltage dividing resistor R13 can also be set according to needs, so that the leakage current meets the performance requirement. The reduction of leakage current can effectively prolong the storage time of the battery, that is, prolong the service time of the battery.

The backlight circuit includes a backlight L1 and a resistor R1. The sixth pin of the microcontroller U1 is connected in series with the resistor R11 to the backlight L1. The backlight is powered by the microcontroller U1. In this embodiment, the display circuit includes a liquid crystal panel P1 and resistors R2-R9. The display circuit is also powered by the microcontroller U1. The reference circuit includes a three-terminal regulator U3 and a second resistor R1. The cathode of the three-terminal regulator U1 is connected to the reference electrode and then connected to the ninth pin of the single-chip microcomputer U1. After the cathode of the three-terminal regulator U1 is connected to the reference electrode, the second resistor R1 is connected in series with the eighth pin of the single-chip microcomputer U1. The anode of the three-terminal regulator U1 is grounded. The reference circuit is used to provide a reference voltage to the single-chip microcomputer U1, so that the single-chip microcomputer U1 can determine the voltage value detected by the voltage detection circuit. The reference circuit is also powered by the microcontroller U1.

The switch circuit includes a tact switch S1 and a first resistor R10. Wherein, one end of the tact switch S1 is respectively connected to the 15th pin (trigger end or trigger pin) of the microcontroller U1 and the first resistor R10; the other end of the tact switch S1 is grounded. The other end of the first resistor R10 is connected to the third pin of the voltage regulator chip U2. Therefore, when the user presses the tact switch S1, the 15th pin of the single chip microcomputer U1 is turned from the original high level VCC to a low level trigger signal. The single-chip microcomputer U1 performs mode switching under the control of the trigger signal. For example, when the power display circuit is in the working mode, that is, when the display circuit and the backlight circuit are all in the working state, after the user presses the tact switch S1, a trigger signal will be formed on the 15th pin of the microcontroller U1. After the single-chip microcomputer U1 receives the trigger signal, it switches modes, and switches from the working mode to the sleeping mode.

In this embodiment, when the single-chip microcomputer U1 receives the low-level signal of the 15th pin, it does not mark it as a trigger signal immediately, but first samples the signal. The single-chip microcomputer U1 will perform multiple continuous sampling at the preset sampling frequency, and judge whether the multiple sampling results are consistent. Only when the multiple sampling results are consistent, the level signal is calibrated as a trigger signal, and the mode is switched according to the trigger signal. , otherwise mark it as a level glitch and end the operation. In this embodiment, the preset sampling frequency is 10 ⁵ Hz, and the sampling frequency is 5000 times, that is, 5000 times of continuous sampling with a sampling period of 10 microseconds. Both the preset sampling frequency and the number of sampling times can be set according to actual needs, and are not limited to the values mentioned in this embodiment. It only needs to be able to identify whether the level signal is a level glitch based on the multiple sampling results. . For example, when the user presses the tact switch to wake up the power display circuit, if the generated level glitch is not recognized and filtered first, the level signal received by the single chip microcomputer U1 will also be reversed, and the single chip microcomputer U1 will be woken up. And when the real trigger signal arrives, it will make the single-chip microcomputer U1 re-enter the sleep mode. Since this process is so fast that the naked eye cannot distinguish it, it is easy for the user to press the tact switch and still fail to wake up the power display circuit, and the user experience is poor. In this embodiment, the single-chip microcomputer U1 will sample the received level signal and judge whether it is a level glitch, so that the level glitch can be filtered out, so that the tact switch S1 will not be falsely triggered, and the false triggering will be reduced. The trigger rate improves the user experience and ease of use.

The present invention also provides a lamp, which includes a battery, a discharge control circuit, and a lighting element, and also includes the power display circuit in any one of the above-mentioned embodiments. Wherein, the battery is connected with the lighting element through the discharge control circuit, and connected with the power display circuit through the power supply input end. Because the power display circuit has the advantages of low power consumption, low leakage current and low misoperation rate, the lamp has a longer battery life.

The present invention also provides a method for controlling a power display circuit, which is used for controlling the power display circuit described in any one of the foregoing embodiments. The flowchart of the control method is shown in FIG. 3 , including the following steps.

S310. Receive a trigger signal from a trigger terminal.

The trigger signal at the trigger terminal is generated when the tact switch is pressed.

S320. Control the control circuit to switch modes according to the trigger signal.

When the trigger signal is received, the control circuit is controlled to switch modes, from the working mode to the sleeping mode or from the sleeping mode to the working mode, and then controls the power display circuit to enter the sleeping mode or the working mode. When the control circuit enters the working mode, the control circuit supplies power to the backlight circuit, the display circuit and the reference circuit and controls the backlight circuit, the display circuit and the reference circuit to work.

In the control method of the power display circuit described above, the mode switching is performed after the trigger terminal of the control circuit receives the trigger signal, and the control circuit supplies power to the backlight circuit, the display circuit and the reference circuit only in the working mode. Therefore, when the control circuit is in the sleep mode, the backlight circuit, the display circuit and the reference circuit do not work, and only the voltage stabilizing circuit and the voltage detection circuit work, so that the leakage current in the sleep mode is small, the power consumption is low, and the battery life is greatly extended. battery storage time.

In this embodiment, the above control method further includes the step of: starting timing when the control circuit enters the working mode, and making the control circuit enter the sleep mode after the timing reaches a preset duration. The above steps can avoid the power loss caused by the long-time display of the power display circuit, and prolong the storage time of the battery.

As shown in FIG. 3 , in this embodiment, steps S410 - S440 are further included before step S310 is executed.

S410. Perform multiple consecutive samplings on the level signal input by the trigger terminal at a preset sampling frequency.

S420, comparing and judging whether the multiple sampling results are the same.

If one or more of the multiple sampling results are different, it can be determined that the multiple sampling results are different, and S430 is executed; otherwise, S440 is executed.

S430. Calibrate the level signal as a trigger signal.

S440. Mark the level signal as a level glitch and end the operation.

In the above control method, the received level signal is sampled and judged whether it is a level glitch, so that the level glitch can be filtered out, so that the light touch switch will not be falsely triggered, reducing the false trigger rate of the system , improving user experience and ease of use.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A power display circuit, comprising a power input terminal for connecting with a battery to receive battery power; it is characterized in that the power display circuit also includes a switch circuit, a control circuit, a voltage stabilizing circuit, a voltage detection circuit, a backlight circuit, display circuit and reference circuit; One end of the switch circuit is respectively connected to the power supply input end and the trigger end of the control circuit, and the other end of the switch circuit is grounded; the switch circuit is used to reverse the level of the trigger end to form a trigger signal ; The control circuit performs mode switching under the control of the trigger signal, switching from the working mode to the sleep mode or switching from the sleep mode to the working mode, and then controlling the power display circuit to enter the sleep mode or the working mode; The voltage stabilizing circuit is respectively connected to the power supply input terminal and the control circuit; the voltage detection circuit is respectively connected to the power supply input terminal and the control circuit; The control circuit is also connected to the backlight circuit, the display circuit and the reference circuit respectively; the control circuit is also used to supply power to the backlight circuit, the display circuit and the reference circuit in the working mode And control the backlight circuit, the display circuit and the reference circuit to work. 2. The power display circuit according to claim 1, wherein the control circuit includes a timer; the timer is used to start counting when the switch circuit triggers the control circuit to enter the working mode; the control The circuit is also used to switch to the dormant mode after the counting of the timer reaches a preset duration. 3. The power display circuit according to claim 1, wherein the switch circuit comprises a tact switch; The control circuit is also used to receive the level signal input by the trigger terminal and compare multiple sampling results after multiple consecutive samplings at a preset sampling frequency, and the control circuit is also used to judge whether the multiple sampling results The same, and when the multiple sampling results are the same, the level signal is marked as a trigger signal; when there is at least one difference in the multiple sampling results, the level signal is marked as a level glitch and end the operation. 4. The power display circuit according to claim 3, wherein the voltage detection circuit comprises a first voltage dividing resistor and a second voltage dividing resistor; one end of the first voltage dividing resistor is connected to the power input terminal The other end of the first voltage dividing resistor is respectively connected to the second voltage dividing resistor and the control circuit; the other end of the second voltage dividing resistor is grounded. 5 . The power display circuit according to claim 3 , wherein the preset sampling frequency is 10 ⁵ Hz, and the sampling frequency is 5000 times. 6. The power display circuit according to claim 3, wherein the control circuit is a single-chip microcomputer, and the switch circuit further includes a first resistor; one end of the tact switch connected to the trigger terminal of the single-chip microcomputer It is also connected to the power supply input terminal through the first resistor. 7. The power display circuit according to claim 6, wherein the reference circuit comprises a three-terminal voltage regulator tube and a second resistor; the cathode of the three-terminal voltage regulator tube is connected to the reference electrode and is connected to the microcontroller connected; after the cathode of the three-terminal voltage regulator is connected to the reference electrode, the second resistor is connected in series and connected to the single-chip microcomputer; the anode of the three-terminal voltage regulator is grounded. 8. A lamp, comprising a battery, a lighting element, and a discharge control circuit; the battery is connected to the lighting element through the discharge control circuit; it is characterized in that it also includes the electric quantity described in any one of claims 1-7 Show the circuit. 9. A method for controlling a power display circuit, used to control the power display circuit according to any one of claims 1 to 7, comprising the steps of: Receive the trigger signal from the trigger terminal; Controlling the control circuit to switch modes according to the trigger signal, switching from the working mode to the sleep mode or switching from the sleep mode to the working mode, and then controlling the power display circuit to enter the sleep mode or the working mode; After the control circuit enters the working mode, the control circuit supplies power to the backlight circuit, the display circuit and the reference circuit and controls the backlight circuit, the display circuit and the reference circuit to work. 10. The method according to claim 9, characterized in that, before the step of receiving the trigger signal of the trigger terminal, the step also includes: performing multiple consecutive samplings of the level signal input by the trigger terminal at a preset sampling frequency; Compare and judge whether the multiple sampling results are the same; If so, the level signal is marked as a trigger signal; If not, mark the level signal as a level glitch and end the operation.