TWI700460B - Desk lamp with power control circuit - Google Patents

Abstract

A desk lamp with a power supply control circuit, comprising: a desk lamp main body provided with a cavity with an entrance; a control circuit arranged in the cavity, which includes a power input unit, a control unit, a lamp delay unit, a power switching unit and a charging unit, The power input unit is electrically connected to the charging unit and the control unit; the power switching unit is electrically connected to the lamp delay unit. In the present invention, the control unit determines whether there is mains connection in the power input unit by detecting the CHG_DET terminal, so as to control CHG_EN to turn on the PMOS tube from high to low potential; in the case of mains connection, the power switch unit The battery does not supply power. When the mains is not connected, the battery supplies power; after the battery is powered off through the switch, the lamp delay unit controls the lamp light to gradually dim until it goes out under the action of the inductance.

Description

Desk lamp with power control circuit

The present invention relates to the field of desk lamps, in particular to a desk lamp with a power control circuit.

In daily life, table lamps are lamps that people use to illuminate small areas. Among them, in order to ensure the normal lighting of the table lamp, the power control circuit is an important component. The power control circuit of the traditional table lamp has a complex structure, low service life and high failure rate; at the same time, when the external power supply is cut off, the table lamp has no backup power supply. When power is supplied, it will be turned off immediately, which will cause damage to the lamp for a long time and cause inconvenience.

At the same time, today’s desk lamps have relatively simple functions. They are only used for lighting purposes, which wastes electric energy. Some assistance tools can be added to them, such as charging functions to charge electronic devices. Therefore, certain improvements to their circuit structure are required. Reach the function of charging.

In view of the above-mentioned problems, the present invention provides a desk lamp with a power control circuit, which can not only effectively control the delay of turning off the lamp of the lamp, protect the lamp and increase its practical life; at the same time, it also adds a charging circuit to charge other devices. , Effectively solve at least one of the above problems.

According to one aspect of the present invention, the present invention provides a desk lamp with a power control circuit, including: a desk lamp main body, the desk lamp main body is provided with a cavity with an inlet; a control circuit, the control circuit is arranged in the cavity, which includes a power source Input unit, control unit, lamp delay unit, power switch The power input unit is electrically connected to the charging unit and the control unit; the power switching unit is electrically connected to the lamp delay unit; the power input unit includes mains Vin, PMOS transistor Q, first resistor R1 and second resistor R2 ; One end of the mains Vin is connected to the drain of the PMOS transistor Q and one end of the first resistor R1, the other end of the first resistor R1 is connected in series with the second resistor R2 and grounded; the control unit includes the CHG_EN end and the CHG_DET end, and the CHG_EN end is connected to the Between a resistor R1 and a second resistor R2, the CHG_DET terminal is connected to the gate of the PMOS transistor Q.

Furthermore, when the mains Vin is powered, the gate of the MOS tube V is at a high potential, the source is at a low potential, and the drain is completely disconnected. The electrical energy is supplied and output by the first diode D1, and the leakage current generated by the power supply passes through the first diode D1. Block; further, the battery GB is powered, the gate of the MOS tube V is grounded at a low potential, the source is at a high potential, the drain is turned on, and the electrical energy is supplied and output by the second diode D2.

Further, the power switching unit includes a MOS tube V, a battery GB, a switch S, a first diode D1 and a second diode D2, the gate of the MOS tube V is connected to the source of the PMOS tube Q, and the MOS tube V The source of the MOS tube is connected to the battery GB, the drain of the MOS tube is connected to the anode of the second diode D2, the anode of the first diode D1 is connected to the gate of the MOS tube, and the cathode of the first diode D1 is connected to the second diode D2. The negative pole of the diode D2 is connected; the switch S is connected between the source of the MOS tube V and the battery GB.

Further, the switch S is a button switch, and the button switch includes a moving contact and a static contact, and the circuit of the button switch is opened or closed through the moving contact and the static contact.

Further, the lamp delay unit includes a lamp L, an inductor Lx and a third resistor R3; the inductor Lx is connected to the negative electrode of the first diode D1 and the negative electrode of the second diode D2, and the lamp L is connected to both ends of the inductor Lx. L is connected in series with the third resistor R3.

Further, the charging unit is a USB interface. The USB interface includes a first pin P1, a second pin P2, and a third pin P3. The first pin P1 is connected between the gate of the MOS transistor V and the source of the PMOS transistor Q Meanwhile, the second pin P2 and the third pin P3 are data transmission pins.

Further, the USB interface is embedded in the entrance of the cavity.

Further, it also includes a circuit board. The circuit board is located in the cavity. The circuit board is provided with a PMOS tube Q, a first resistor R1, a second resistor R2, a control unit, a MOS tube V, a first diode D1, and a second diode. Polar body D2, inductance Lx and third resistance R3.

The present invention has the following beneficial effects: 1. The power input unit cooperates with the control unit. When the mains Vin is connected, the control unit determines whether the mains Vin is connected by detecting the CHG_DET terminal, thereby controlling CHG_EN from high potential to low potential. Turn on the PMOS tube Q to act as an automatic switch; 2. In the power switching unit, the MOS tube V, the battery GB, the first diode D1 and the second diode D2 cooperate. When the mains Vin is connected, the battery GB No power supply, when the mains Vin is not connected, the battery GB provides power; 3. In the lamp delay unit, the lamp L is connected to both ends of the inductor Lx. After the battery GB is powered off through the switch S, the battery GB is connected to the inductor Lx. Under the action of, the light of lamp L gradually dims until it goes out.

1: charging unit

2: Power switching unit

3: Lamp delay unit

4: control unit

5: Power input unit

Vin: mains

GB: battery

S: switch

Q: PMOS tube

R1: first resistance

R2: second resistor

V: MOS tube

D1: The first diode

D2: The second diode

Lx: inductance

R3: third resistor

Figure 1 is a schematic diagram of the structure of the present invention; Figure 2 is a circuit diagram of the present invention.

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

Fig. 1 schematically shows a structural diagram of an embodiment of the present invention.

Example one:

A desk lamp with a power control circuit, including a desk lamp body, the desk lamp body is provided with a cavity with an inlet, so that the cavity is used to house the control circuit and protect it. The shape of the desk lamp body can be a commercially available desk lamp Any kind of shape.

As shown in Figure 1, a control circuit is arranged in the cavity, which includes a power input unit 5, a control unit 4, a lamp delay unit 3, a power switch unit 2 and a charging unit 1, and the power input unit 5 is electrically connected The charging unit 1 and the control unit 4; the power switching unit 2 is electrically connected to the lamp delay unit 3.

As shown in Figure 2, the power input unit 5 includes a mains Vin, a PMOS transistor Q, a first resistor R1 and a second resistor R2; one end of the mains Vin is connected to the drain of the PMOS transistor Q and one end of the first resistor R1, The other end of the resistor R1 is connected in series with a second resistor R2 and grounded; the control unit 4 includes a CHG_EN end and a CHG_DET end. The CHG_EN end is connected between the first resistor R1 and the second resistor R2, and the CHG_DET end is connected to the gate of the PMOS transistor Q.

Specifically, when the mains power Vin is connected, the control unit 4 determines whether there is mains power connection by detecting the CHG_DET terminal, thereby controlling CHG_EN to turn on the PMOS tube Q from high to low potential, acting as an automatic switch. The control unit 4 uses the power supply The chip performs control, such as a power chip with the model WS3255.

As shown in FIG. 2, the power switching unit 2 includes a MOS tube V, a battery GB, a switch S, a first diode D1 and a second diode D2, the gate of the MOS tube V and the source of the PMOS tube Q Connected, the source of the MOS tube V is connected to the battery GB, the drain of the MOS tube is connected to the anode of the second diode D2, the anode of the first diode D1 is connected to the gate of the MOS tube, the first diode The negative electrode of D1 is connected to the negative electrode of the second diode D2; the switch S is connected between the source of the MOS tube V and the battery GB.

In this embodiment, when the mains Vin is supplying power, the gate of the MOS transistor V is at a high potential, the source is at a low potential, and the drain is completely disconnected. The electric energy is supplied and output through the first diode D1, and the leakage caused by the power supply The flow is completely blocked by the first diode D1; when the battery GB is powered, the gate of the MOS tube V is grounded at a low potential, the source is at a high potential, and the drain is turned on, and supplies and outputs through the second diode D2.

Switch S is a button switch. The button switch includes a moving contact and a static contact. The circuit of the button switch is opened or closed through the moving contact and the static contact, thereby realizing the conduction and closing of the battery GB circuit, thereby prompting the battery GB to deliver electric energy .

As shown in Figure 2, the lamp delay unit 3 includes a lamp L, an inductor Lx and a third resistor R3; the inductor Lx is connected to the negative electrode of the first diode D1 and the negative electrode of the second diode D2, and the lamp L is connected to the inductor Lx At both ends of the lamp L and the third resistor R3 are connected in series.

In this embodiment, when the battery GB stops supplying power, there is still a certain current in the inductor Lx, and there are the following three situations: Case 1: If the coil current of the inductor Lx is greater than the current in the lamp L, when the power is off, the lamp L The current passing through the lamp L is greater than the current passing through the lamp L, so the lamp L will be brighter and then slowly extinguished; Case 2: If the coil current of the inductor Lx is equal to the current in the lamp L, when the power is off, the current passing through the lamp L is equal to the original passing The current of the lamp L, so the lamp L is extinguished directly from the original brightness; Case 3: If the coil current of the inductor Lx is less than the current in the lamp L, when the power is off, the current passing through the lamp L is less than the original passing through the lamp L Electric current, then the lamp L suddenly becomes darker and then slowly goes out.

As shown in Figure 2, the charging unit 1 is a USB interface. The USB interface includes a first pin P1, a second pin P2, and a third pin P3. The first pin P1 is connected to the gate of the MOS transistor V and the PMOS transistor. Between the sources of Q, the second pin P2 and the third pin P3 are data transmission pins.

In this embodiment, the USB interface is embedded at the entrance of the cavity. Since the first pin P1 is connected between the gate of the MOS tube v and the source of the PMOS tube Q, the power output from the source of the PMOS tube Q is connected It is transmitted to USB via P1, and when the storage device is connected to P2 and P3, the electric energy is transmitted to the storage device to realize the charging function.

In the present invention, the lamp L, the USB interface and the switch S are exposed or embedded in the main body of the lamp, the battery GB is built in the cavity, and other components can be connected through the circuit board, which is convenient for installation and debugging, such as PMOS tube Q, The first resistor R1, the second resistor R2, the control unit, the MOS tube V, the first diode D1, the second diode D2, the inductor Lx, and the third resistor R3.

The above are only some embodiments of the present invention. For those of ordinary skill in the art, without departing from the inventive concept of the present invention, several modifications and improvements can be made, and these all fall within the protection scope of the present invention.

Vin: mains

GB: battery

S: switch

Q: PMOS tube

R1: first resistance

R2: second resistor

V: MOS tube

D1: The first diode

D2: The second diode

Lx: inductance

R3: third resistor

Claims (9)

A desk lamp with a power control circuit, including: A lamp main body provided with a cavity with an entrance; and A control circuit is arranged in the cavity, the control circuit includes: a power input unit, a control unit, a lamp delay unit, a power switch unit and a charging unit, among them, The power input unit is electrically connected to the charging unit and the control unit; The power switching unit is electrically connected to the lamp delay unit; The power input unit includes a mains power, a PMOS tube, a first resistor, and a second resistance; one end of the mains power is connected to the drain of the PMOS tube and one end of the first resistor, and the other end of the first resistor is connected in series. The second resistor is connected to ground; The control unit includes a CHG_EN terminal and a CHG_DET terminal, the CHG_EN terminal is connected between the first resistor and the second resistor, and the CHG_DET terminal is connected to the gate of the PMOS transistor. The table lamp with a power supply control circuit according to claim 1, wherein: The mains power supply; The power switching unit includes a MOS tube. When the gate of the MOS tube is at a high potential, the source is at a low potential, and the drain is completely disconnected, electric energy is supplied and output by the first diode, and the leakage current generated by the power supply passes through the The first diode is completely blocked. The table lamp with a power supply control circuit according to claim 1, wherein: The power switching unit includes a MOS tube, a battery, a switch, a first diode and a second diode, the gate of the MOS tube is connected to the source of the PMOS tube, and the source of the MOS tube is connected to The drain of the MOS tube is connected to the anode of the second diode, the anode of the first diode is connected to the gate of the MOS tube, and the cathode of the first diode is connected to the battery. It is connected with the negative electrode of the second diode, and the switch is connected between the source of the MOS tube and the battery. The table lamp with a power control circuit according to claim 3, wherein: Powered by the battery; When the gate of the MOS transistor is at a low potential, the source is at a high potential, and the drain is turned on, electrical energy is supplied and output by the second diode. The desk lamp with a power supply control circuit according to claim 3, wherein the switch is a button switch, the button switch includes a moving contact and a static contact, and the circuit of the button switch passes through the moving contact and The static contact is open or closed. The desk lamp with a power control circuit according to claim 1, wherein the lamp delay unit includes a lamp, an inductor, and a third resistor, and the inductor is connected to the negative electrode of the first diode and the negative electrode of the second diode The lamp is connected in series with the third resistor, and the lamp is connected to both ends of the series circuit of the inductor and the third resistor. The desk lamp with a power control circuit according to claim 1, wherein the charging unit is a USB interface, and the USB interface includes a first pin, a second pin, and a third pin, the first pin Connected between the gate of the MOS tube and the source of the PMOS tube, the second pin and the third pin are data transmission pins. The desk lamp with a power control circuit according to claim 7, wherein the USB interface is embedded in the entrance of the cavity. The desk lamp with a power supply control circuit according to any one of claims 1-8, further comprising a circuit board, the circuit board is located in the cavity, the circuit board is provided with a PMOS tube, a first Resistor, second resistor, control unit, MOS tube, first diode, second diode, inductor and third resistor.

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