Multi-path light emitting diode constant-current constant-light-power driving circuit and electronic equipment

Abstract

The invention is mainly used in the technical field of photoelectric semiconductors. The invention discloses a constant-current constant-light power driving circuit for multiple paths of light-emitting diodes and electronic equipment. The circuit comprises a power supply unit, a light-emitting unit, a power tube unit and a control unit, the power supply unit is connected with the light-emitting unit and used for transmitting a voltage signal to the light-emitting unit; the power tube unit is connected with the light-emitting unit and used for adjusting the current of the light-emitting unit so as to control the light-emitting unit to be in a constant current state; and the control unit is respectively connected with the power supply unit and the power tube unit and is used for monitoring the power tube unit and adjusting the voltage signal through the power supply unit according to the monitored signal so as to control the voltage value of the power tube unit to be within a first target value range. The light-emitting diode can be in a current constant state or an ultraviolet energy constant state, and meanwhile the power tube is protected.

Description

Technical Field

[0001] The invention relates to the technical field of optoelectronic semiconductors, and in particular to a multi-channel light emitting diode constant current constant light power driving circuit and electronic equipment. Background Art

[0002] In the relevant field, the core of the LED linear constant current drive circuit is the power tube. In the constant current state, the power tube works in the linear region. When the external power supply voltage rises, the voltage drop of the power tube also rises accordingly. When the external power supply voltage drops, the voltage drop of the power tube also drops accordingly, so that the voltage on the LED lamp bead remains unchanged, and finally the purpose of constant current of the LED lamp bead is achieved. However, when the input voltage increases, the LED lamp bead current decreases, or the LED lamp bead temperature rises, the voltage drop of the power tube will increase, further increasing the power consumption of the power tube and increasing the temperature. When the temperature of the power tube continues to accumulate, it will cause the power tube to be damaged. Summary of the invention

[0003] The invention provides a multi-channel light emitting diode constant current constant light power driving circuit and electronic equipment, which can keep the light emitting diode in a constant current state and protect the power tube at the same time.

[0004] The present invention provides a multi-channel light emitting diode constant current constant light power driving circuit, the circuit comprising a power supply unit, a light emitting unit, a power tube unit and a control unit; The power supply unit is connected to the light emitting unit and is used to transmit a voltage signal to the light emitting unit; The power tube unit is connected to the light-emitting unit and is used to adjust the current of the light-emitting unit to control the light-emitting unit to be in a constant current state; The control unit is connected to the power supply unit and the power tube unit respectively, and is used to monitor the power tube unit and adjust the voltage signal through the power supply unit according to the monitored signal to control the voltage value of the power tube unit to be within the first target value range.

[0005] Furthermore, the control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and issue an alarm notification of the power tube unit abnormality when it is detected that the voltage value of the power tube unit is within a first abnormal value range.

[0006] Further, the circuit further comprises a first sensor unit; The first sensor unit is connected to the control unit and is used to collect the temperature value of the light-emitting unit and transmit it to the control unit; The control unit is used to adjust the voltage signal through the power supply unit based on the power tube voltage drop value detected from the power tube unit and the temperature value, so as to control the voltage value of the power tube unit to be within a second target value range; The control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and issue an alarm notification of abnormal light emitting unit temperature when it is detected that the temperature value of the light emitting unit is within a second abnormal value range.

[0007] Furthermore, the control unit is further used to save the power tube pressure difference value monitored by the power tube unit as a historical pressure difference value; The control unit is further used to determine the difference between the current power tube pressure difference value and the historical pressure difference value, and to issue an alarm notification when the difference is greater than a preset difference.

[0008] Further, the circuit further comprises a second sensor unit; The second sensor unit is connected to the control unit and is used to collect the ultraviolet light power signal of the light emitting unit and transmit it to the control unit; The control unit is used to compare the ultraviolet light power signal with a preset ultraviolet light power given signal to obtain an ultraviolet light power error value, and send adjustment signals to the power tube unit and the power supply unit respectively according to the ultraviolet light power error value to control the ultraviolet light power value of the light-emitting unit to be equal to a preset threshold value; The power tube unit is used to adjust the current of the light-emitting unit when the adjustment signal is obtained; The power supply unit is used to adjust the voltage signal transmitted to the light emitting unit when the adjustment signal is acquired.

[0009] Further, the circuit comprises a plurality of the light-emitting units and a plurality of the power tube units; each of the light-emitting units is connected to one of the power tube units to form a plurality of integrated light-emitting units; The power supply unit is respectively connected to the light-emitting units in each of the integrated light-emitting units, and transmits the same parallel voltage signal to each of the integrated light-emitting units; The control unit is respectively connected to the power tube unit in each of the integrated light-emitting units, and is used to adjust the parallel voltage signal through the power supply unit according to the signal monitored from the target integrated light-emitting unit among the multiple integrated light-emitting units, so as to control the voltage value of the power tube unit in each of the integrated light-emitting units to be within a third target value range.

[0010] Furthermore, the circuit further comprises a plurality of the second sensor units; each light emitting unit of the integrated light emitting unit corresponds to one of the second sensor units; The power supply unit comprises a plurality of power switch modules, each of which is connected to one of the integrated light emitting units; Each of the second sensor units is used to collect the ultraviolet light power signal of the target light-emitting unit according to the corresponding relationship and transmit it to the control unit to determine the light power corresponding to each of the integrated light-emitting units; The power supply unit is further used to adjust the current transmitted to each of the integrated light-emitting units through each of the switch modules, until the optical power corresponding to each of the integrated light-emitting units is equal to the corresponding target optical power.

[0011] Further, the power tube unit includes a power tube module and a negative feedback regulation module; The first end of the power tube module is used to connect the light-emitting unit, the second end of the power tube module is connected to the second input end of the negative feedback regulation module, and the third end of the power tube module is connected to the output end of the negative feedback regulation module; The first input terminal of the negative feedback regulation module is connected to the first control signal output terminal of the control unit.

[0012] Further, the power tube module includes a power tube, a first resistor, a second resistor and a third resistor; The first end of the power tube serves as the first end of the power tube module, the second end of the power tube serves as the second end of the power tube module, and the third end of the power tube serves as the third end of the power tube module; One end of the first resistor is connected to the first end of the power tube, and the other end of the first resistor is connected to the first sampling signal input end of the control unit; One end of the second resistor is connected to the other end of the first resistor, and the other end of the second resistor is connected to the negative output end of the power supply unit; One end of the third resistor is connected to the second end of the power tube, and the other end of the third resistor is connected to the negative output end of the power supply unit.

[0013] Further, the sampling signal output terminal of the power supply unit is connected to the second sampling signal input terminal of the control unit, and the control signal input terminal of the power supply unit is connected to the second control signal output terminal of the control unit; The control unit is used to obtain a power sampling signal through the second sampling signal input terminal of the control unit, generate a power control signal according to the power sampling signal, and transmit the power control signal to the power supply unit through the second control signal output terminal of the control unit.

[0014] The present invention also provides an electronic device, comprising the multi-channel light emitting diode constant current constant light power driving circuit as described in any one of the above items.

[0015] The present invention has at least the following beneficial effects: In the technical solution of the present application, the control unit monitors the working state of the power tube unit and adjusts the voltage signal output by the power supply unit according to the monitoring signal. In this way, even if the external power supply voltage rises or falls, the control unit can keep the voltage value of the power tube or power tube in the power tube unit within the first target value range by adjusting the voltage signal to avoid excessive pressure difference of the power tube or power tube. Therefore, the technical solution of the present application can effectively avoid the risk of damage to the power tube or power tube due to excessive pressure difference while maintaining a constant current state for the LED lamp beads in the light-emitting unit, thereby improving the stability and life of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0017] Figure 1 This is a structural schematic diagram of a multi-channel light emitting diode constant current constant light power driving circuit of this embodiment; Figure 2 1 is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of the present embodiment; Figure 3 1 is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of the present embodiment; Figure 4 1 is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of the present embodiment; Figure 5 This is a flow chart of the implementation of the internal program of the control unit in the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment; Figure 6 4 is a circuit diagram of a multi-channel light emitting diode constant current constant light power driving circuit of this embodiment. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] In the relevant technical field, the common light-emitting diode (LED) driving circuit is to achieve stable current driving of LED through a constant current source and a current feedback control circuit. The core of the constant current source is the power tube. In the constant current state, the power tube works in the linear region and acts as a resistor. When the external power supply voltage rises (falls), the voltage drop on the power tube also rises (falls) accordingly, so that the voltage on the LED lamp bead remains unchanged, and finally the purpose of constant current of the LED lamp bead is achieved.

[0020] The current feedback control circuit usually consists of LED current setting, LED current sampling feedback, and error amplifier, and usually adopts negative feedback control method. When the current in the LED increases (decreases) due to some reasons, the increased (decreased) current acts on the reverse input terminal of the error amplifier through the current sampling resistor, and the negative feedback structure will reduce (increase) the gate voltage of the power tube. Finally, the LED lamp bead current is stabilized at a given value, thereby achieving dynamic balance and achieving the purpose of constant current.

[0021] The researchers of this application found that the common linear constant current source input voltage is basically fixed, and the input voltage is equal to the sum of the voltage of the LED light string and the voltage of the power tube. In order to achieve constant current of the LED lamp beads, when the input voltage increases, the LED lamp bead current setting decreases, and the LED lamp bead temperature increases, the voltage difference on the power tube will increase, further increasing the power consumption of the power tube and raising the temperature. When the temperature continues to accumulate and the heat dissipation is poor, it will affect the life of the power tube or even burn it out. Since the input voltage of the linear constant current source is fixed, the input voltage cannot be adjusted online, and the efficiency of the circuit is relatively low.

[0022] In addition, with the long-term use of LED lamp beads, the lamp beads may gradually age, die or fail. When some LED lamp beads in the light string fail due to short circuit, in order to achieve constant current control of the remaining LED light strings, the voltage drop of the short-circuited and failed LED lamp beads is forced to increase on the MOS. As the use time goes by, the number of failed LEDs increases, causing the pressure difference on the power tube to continue to increase, and the heat of the power tube continues to accumulate, which may eventually damage the power tube and burn out the LED lamp beads. When some LED lamp beads fail due to short circuit or the LED light string is short-circuited due to external reasons, since it is impossible to detect the pressure difference on the power tube, it is impossible to protect the circuit and the external alarm output function.

[0023] Please refer to Figure 1 , Figure 1It is a structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0024] This embodiment provides a multi-channel light emitting diode constant current constant light power driving circuit including a power supply unit, a light emitting unit, a power tube unit and a control unit.

[0025] The power supply unit is connected to the light-emitting unit and is used to transmit a voltage signal to the light-emitting unit.

[0026] The power tube unit is connected to the light-emitting unit and is used to adjust the current of the light-emitting unit to control the light-emitting unit to be in a constant current state.

[0027] The control unit is connected to the power supply unit and the power tube unit respectively, and is used to monitor the power tube unit and adjust the voltage signal through the power supply unit according to the monitored signal to control the voltage value of the power tube unit to be within the first target value range.

[0028] In some embodiments, the control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and provide an alarm notification of an abnormality of the power tube unit when it is detected that the voltage value of the power tube unit is within a first abnormal value range.

[0029] It can be understood that in the technical solution of the present application, the control unit monitors the working state of the power tube unit and adjusts the voltage signal output by the power supply unit according to the monitoring signal. In this way, even if the external power supply voltage rises or falls, the control unit can keep the voltage value of the power tube in the power tube unit within the first target value range by adjusting the voltage signal to avoid excessive voltage difference of the power tube. Specifically, when the input voltage increases or the current of the LED lamp bead in the light-emitting unit decreases, the control unit detects that the voltage difference of the power tube increases, and reduces the voltage signal through the power supply unit to reduce the voltage difference and power consumption of the power tube and prevent the temperature from rising. On the contrary, when the input voltage drops or the current of the LED lamp bead in the light-emitting unit increases, the control unit increases the voltage signal to keep the voltage difference and power consumption of the power tube within a reasonable range.

[0030] It can be seen that the technical solution of the present application can effectively avoid the risk of power tube damage due to excessive voltage difference while maintaining a constant current state for the LED lamp beads in the light-emitting unit, thereby improving the stability and life of the circuit.

[0031] Please refer to Figure 2 , Figure 2 This is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0032] In some embodiments, the multi-channel light emitting diode constant current constant light power driving circuit further includes a first sensor unit.

[0033] The first sensor unit is connected to the control unit and is used to collect the temperature value of the light-emitting unit and transmit it to the control unit.

[0034] The control unit is used to adjust the voltage signal through the power supply unit based on the power tube voltage drop value and temperature value detected from the power tube unit, so as to control the voltage value of the power tube unit to be within the second target value range.

[0035] In some embodiments, the control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and issue an alarm notification of abnormal light emitting unit temperature when it is detected that the temperature value of the light emitting unit is within a second abnormal value range.

[0036] It can be understood that this embodiment realizes constant current and constant light power driving of multiple light emitting diodes (LEDs) by integrating the control unit, the power tube unit and the first sensor unit. The control unit monitors the power tube voltage drop and the LED temperature, and dynamically adjusts the voltage signal output by the power supply unit to keep the power tube voltage within the target range, ensuring constant LED current and stable light power. The introduction of the temperature sensor enables the system to monitor the LED temperature in real time. When an abnormally high temperature is detected, the control unit will cut off the power supply and issue an alarm to protect the LED from thermal damage and improve the safety and reliability of the system.

[0037] In some embodiments, the control unit is further configured to save the power tube pressure difference value monitored from the power tube unit and use it as a historical pressure difference value.

[0038] The control unit is also used to determine the difference between the current power tube pressure difference value and the historical pressure difference value, and when the difference is greater than a preset difference, an alarm notification is issued.

[0039] It is understandable that in the light-emitting unit, any change in the current will lead to a corresponding change in the power tube voltage difference value. For example, if the light-emitting diodes in the light-emitting unit are damaged or the number increases, the current will change. In order to keep the current of the light-emitting unit stable, the power tube voltage difference value of the power tube unit must be adjusted accordingly.

[0040] In this embodiment, each time the power tube pressure difference value changes, the changed pressure difference value will be saved as a historical pressure difference value. Specifically, the control unit saves the initial power tube pressure difference value when each light-emitting diode in the light-emitting unit works normally as the initial historical pressure difference value. Subsequently, the control unit monitors and records the power tube pressure difference value in the current state, and compares it with the initial historical pressure difference value to calculate the difference.

[0041] In a specific embodiment, by comparing the current power tube pressure difference value with the initial historical pressure difference value, the number of normally working LEDs in the light-emitting unit in the current state can be estimated. If the calculated difference exceeds a preset threshold, the control unit will issue an alarm notification. This indicates that the number of abnormally working LEDs in the light-emitting unit in the current state has exceeded expectations, indicating that the light-emitting unit needs to be repaired.

[0042] In some embodiments, the circuit includes a plurality of light-emitting units and a plurality of power tube units; each light-emitting unit is connected to a power tube unit to form a plurality of integrated light-emitting units.

[0043] The power supply unit is respectively connected to the light-emitting units in each integrated light-emitting unit, and transmits the same parallel voltage signal to each integrated light-emitting unit.

[0044] The control unit is respectively connected to the power tube unit in each integrated light-emitting unit, and is used to adjust the parallel voltage signal through the power supply unit according to the signal monitored from the target integrated light-emitting unit among the multiple integrated light-emitting units, so as to control the voltage value of the power tube unit in each integrated light-emitting unit to be within the third target value range.

[0045] It is understandable that, in this embodiment, the power supply unit is responsible for connecting multiple integrated light-emitting units. Each integrated light-emitting unit includes a power tube unit and a light-emitting unit. The voltage signal output by the power supply unit can simultaneously affect the voltage of all integrated light-emitting units, thereby affecting the voltage of each power tube unit and the light-emitting unit.

[0046] When adjusting the voltage signal output by the power supply unit, the specific voltage requirements of the target integrated light-emitting unit must be taken into account. For example, when the power supply unit needs to transmit a voltage signal to multiple integrated light-emitting units, if the goal is to reduce the voltage signal, the integrated light-emitting unit with the lowest voltage should be selected as the adjustment target, and the lowest normal operating voltage of the power tube voltage drop in the unit should be referred to to determine the target value range for reducing the voltage signal. Then, based on this target value range, the voltage signal output by the power supply unit is appropriately reduced. It should be noted that if the voltage signal output by the power supply unit is reduced too much, the power tube in the integrated light-emitting unit with the lowest voltage may not work properly.

[0047] Similarly, when the voltage signal output by the power supply unit needs to be increased, the integrated light-emitting unit with the highest voltage should be selected as the adjustment target, and the voltage drop of the power tube in the unit should be referred to to determine the target value of the voltage signal output by the power supply unit. In this way, it can be ensured that the power tube units and light-emitting units in all integrated light-emitting units can work normally at the appropriate voltage.

[0048] Please refer to Figure 3 , Figure 3 This is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0049] In some embodiments, the multi-channel light emitting diode constant current constant light power driving circuit further includes a second sensor unit.

[0050] The second sensor unit is connected to the control unit and is used for collecting the ultraviolet light power signal of the light emitting unit and transmitting it to the control unit.

[0051] The control unit is used to compare the ultraviolet light power signal with a preset ultraviolet light power given signal to obtain an ultraviolet light power error value, and send adjustment signals to the power tube unit and the power supply unit respectively according to the ultraviolet light power error value to control the ultraviolet light power value of the light-emitting unit to be equal to a preset threshold value.

[0052] The power tube unit is used to adjust the current of the light-emitting unit when the adjustment signal is obtained.

[0053] The power supply unit is used to adjust the voltage signal transmitted to the light-emitting unit when the adjustment signal is obtained.

[0054] In some embodiments, the control unit has two working modes: a first mode and a second mode. In these two modes, the working state of the sensor unit will be different. In the first mode, the control unit adjusts the output voltage through the power supply unit according to the power tube voltage difference value. The control unit also detects the ultraviolet light power signal through the second sensor unit. Once the ultraviolet light power signal is detected, the control unit will automatically switch to the constant power mode, that is, the second mode. In the constant power mode, the control unit will detect the light signal of each light-emitting unit. After the detection is completed, the control unit will adjust the current for a certain light-emitting unit by controlling the power tube unit of the road. By adjusting the current, the control unit can adjust the light power of the light-emitting unit of the road, thereby changing the light signal. The control unit achieves precise control of the light power of the light-emitting unit by switching between the two modes.

[0055] Please refer to Figure 4 , Figure 4 This is another structural schematic diagram of the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0056] See also Figure 4 In some embodiments, the circuit includes a plurality of light-emitting units and a plurality of power tube units; each light-emitting unit is connected to a power tube unit to form a plurality of integrated light-emitting units. The power supply unit is respectively connected to the light-emitting units in each integrated light-emitting unit and transmits the same parallel voltage signal to each integrated light-emitting unit. Each integrated light-emitting unit is matched with a second sensor unit.

[0057] The circuit also includes a plurality of second sensor units; the light emitting unit of each integrated light emitting unit corresponds to a second sensor unit; the power supply unit includes a plurality of power switch modules, and each power switch module is connected to an integrated light emitting unit.

[0058] Each second sensor unit is used to collect the ultraviolet light power signal of the target light-emitting unit according to the corresponding relationship and transmit it to the control unit to determine the light power corresponding to each integrated light-emitting unit.

[0059] The power supply unit is also used to adjust the current transmitted to each integrated light-emitting unit through each switch module until the optical power corresponding to each integrated light-emitting unit is equal to the corresponding target optical power.

[0060] By measuring the ultraviolet light power error value of each integrated light-emitting unit, the integrated light-emitting unit that is not working properly can be identified. For these abnormal units, it is not necessary to adjust the voltage signal transmitted to all integrated light-emitting units through the power supply unit. Instead, an adjustment signal can be directly sent to the power tube unit in the integrated light-emitting unit that is not working properly, and the current can be adjusted through the power tube unit to restore the normal working state of the integrated light-emitting unit.

[0061] If the second sensor unit detects that multiple integrated light-emitting units have problems at the same time, it can send an adjustment signal to the power supply unit, which adjusts the output voltage and performs unified voltage adjustment on multiple abnormally working integrated light-emitting units to help them return to normal working state. For the integrated light-emitting units that have not returned to normal after voltage adjustment, they can be further adjusted by adjusting the current through the power tube unit to ensure that all integrated light-emitting units can return to normal working state.

[0062] The circuit design of this embodiment allows accurate current or voltage regulation of a single or multiple abnormally functioning integrated light-emitting units to quickly and effectively restore their normal functions. This design can improve the reliability and maintenance efficiency of the circuit.

[0063] It is understandable that the power tube unit of each integrated light-emitting unit can be switched between a working state and a cut-off state. When the power tube unit of any integrated light-emitting unit is in the cut-off state, the circuit where the integrated light-emitting unit is located is in an open circuit state, the current is zero, and the light-emitting unit of the integrated light-emitting unit stops working.

[0064] In some embodiments, the control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and provide an alarm notification of energy abnormality of the light emitting unit when it is detected that the ultraviolet light power value of the light emitting unit is within a third abnormal value range.

[0065] In this embodiment, constant current and constant light power drive is achieved by precisely controlling the current and ultraviolet light power of multiple light emitting diodes (LEDs). The voltage of the light emitting unit is adjusted by the power tube unit to keep the current constant. The control unit monitors the voltage drop of the power tube and dynamically adjusts the voltage signal to ensure the stability of the power tube voltage. The second sensor unit collects the ultraviolet light power signal, and the control unit compares the preset value and adjusts the voltage to match the preset light power to achieve precise light power control. The abnormal light power detection function cuts off the power supply and alarms when an abnormality is detected to protect the LED and ensure safety. The overall stability and reliability of the system are improved, while ensuring the consistency and efficiency of LED lighting.

[0066] It can be understood that, on the basis of the above-mentioned embodiment, by monitoring the voltage value of the power tube unit, detecting the temperature value of the light-emitting unit through the first sensor unit, and detecting the ultraviolet light power signal of the light-emitting unit through the second sensor unit, when the LED lamp bead fails due to a short circuit, the voltage value of the power tube unit, the temperature value of the light-emitting unit, and the changes in the ultraviolet light power signal of the light-emitting unit are monitored in real time, thereby detecting this abnormal situation of the LED lamp bead and outputting an alarm in time, and in severe cases, the DC bus voltage can be directly cut off to achieve self-protection.

[0067] Please refer to Figure 5 , Figure 5 It is a flow chart of the internal program implementation of the control unit in the multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0068] In this embodiment, the control unit may be a central processing unit such as a single chip microcomputer with computing capabilities. After startup, the central processing unit executes a pre-stored program to implement the following steps: First, after startup, the system goes through the "Start" node and then "initializes peripherals such as ADC, DAC, and USART". Next, it determines whether the program self-test is normal. If the self-test fails, the system will jump directly back to the "Start" node and re-initialize. This step ensures that the system is in a normal state before continuing.

[0069] Assuming the self-test passes, the system will continue with three parallel test processes: The system will check whether the voltage of the power tube is normal. If the voltage is normal, the system will control the output voltage of the LED constant voltage source according to the drain voltage of the power tube. If the voltage is abnormal, an alarm will be triggered, the light will be turned off, and the abnormal state will be reported.

[0070] The system will check whether the UV energy of the LED in the light-emitting unit is normal. If the UV energy is normal, the process continues; if it is abnormal, it will also trigger an alarm, turn off the light, and report the abnormal state.

[0071] The system will check whether the temperature of the LED module is normal. If the temperature is normal, the process continues; if it is not normal, an alarm will be triggered, the light will be turned off, and the abnormal status will be reported.

[0072] These three detection processes are carried out in parallel. If any of the detection fails, the system will enter the abnormal processing process. If there is a problem in any detection step, the system will alarm, turn off the light and report the abnormal status.

[0073] If all tests pass, the system will continue to wait for "receiving the host computer startup and light power setting command". Once the command is received, the system will start the LED constant voltage source and LED constant ultraviolet light power control, and then perform LED constant current control. This step ensures that the LED works at a constant current to ensure the stability of the light power.

[0074] Finally, the system will report the working status information such as LED module switch, module temperature, UV light power, MOS voltage difference, etc. to ensure that all parameters are within the normal range, and report this information to the host computer.

[0075] It can be understood that any failure of detection in this embodiment will cause the system to enter abnormal processing, ensuring the safe and stable operation of the system. The entire process has clear logic and ensures that all key parameters are within the normal range, so that the entire multi-channel light-emitting diode constant current and constant light power drive circuit can operate normally.

[0076] In some embodiments, the power tube unit includes a power tube module and a negative feedback regulation module.

[0077] The first end of the power tube module is used to connect to the light-emitting unit, the second end of the power tube module is connected to the second input end of the negative feedback regulation module, and the third end of the power tube module is connected to the output end of the negative feedback regulation module; the first input end of the negative feedback regulation module is connected to the first control signal output end of the control unit.

[0078] In some embodiments, the negative feedback regulation module is an error amplifier.

[0079] In some embodiments, the power tube module includes a power tube, a first resistor, a second resistor and a third resistor; the first end of the power tube serves as the first end of the power tube module, the second end of the power tube serves as the second end of the power tube module, and the third end of the power tube serves as the third end of the power tube module; one end of the first resistor is connected to the first end of the power tube, and the other end of the first resistor is connected to the first sampling signal input end of the control unit; one end of the second resistor is connected to the other end of the first resistor, and the other end of the second resistor is connected to the negative output end of the power supply unit; one end of the third resistor is connected to the second end of the power tube, and the other end of the third resistor is connected to the negative output end of the power supply unit.

[0080] In some embodiments, the sampling signal output terminal of the power supply unit is connected to the second sampling signal input terminal of the control unit, and the control signal input terminal of the power supply unit is connected to the second control signal output terminal of the control unit.

[0081] The control unit is used to obtain a power sampling signal through the second sampling signal input terminal of the control unit, generate a power control signal according to the power sampling signal, and transmit the power control signal to the power supply unit through the second control signal output terminal of the control unit.

[0082] Please refer to Figure 6 , Figure 6 4 is a circuit diagram of a multi-channel light emitting diode constant current constant light power driving circuit of this embodiment.

[0083] In this embodiment, the light-emitting unit includes an LED light string; the power tube Q1 is a MOS tube; the first resistor R1 and the second resistor R2 are both Vds voltage drop sampling resistors of the power tube Q1; the third resistor R3 is a sampling resistor for current detection of the LED light string; the second sensor unit includes a sensor S1, which is an ultraviolet energy sensor (UV energy sensor); the first sensor unit includes a sensor S2, which is a temperature sensor. The negative feedback regulation module is an error amplifier; and the control unit is a central processing unit CPU.

[0084] The DIM signal output by the central processing unit CPU is input to the positive input terminal of the error amplifier, and the negative input terminal of the error amplifier is connected to the collector of the power tube Q1 through the third resistor R3. The output terminal of the error amplifier is connected to the base of the power tube Q1 through the first resistor R1 to control its conduction and cutoff. The error amplifier compares the DIM signal with the feedback signal. According to the comparison result, the voltage output to the base of the transistor Q1 is adjusted to control the conduction degree of Q1. The emitter of the power tube Q1 is connected to the ground (V-), and its collector is connected to the output terminal of the LED string through the second resistor R2.

[0085] The third resistor R3 is the current sensing resistor of the LED light string, which converts the current into a voltage signal through the third resistor R3 and connects it to the reverse input terminal of the error amplifier. When the DIM setting changes or the LED light string current changes due to external reasons, the negative feedback of the current detection will keep the actual current of the LED light string at the set value.

[0086] The outputs of sensor S1 and sensor S2 are connected to the central processing unit CPU. The UV energy sensor and temperature sensor monitor the environmental conditions and send analog signals to the central processing unit CPU. The central processing unit CPU converts the analog signals into digital signals for calculation. The central processing unit CPU adjusts the DIM signal or outputs a control signal to the LED constant voltage power supply by converting the digital signal into an analog signal.

[0087] The first resistor R1 and the second resistor R2 are both voltage-dividing sampling resistors for the drain voltage of the power tube Q1, which reduce the voltage of the power drain to within the ADC range of the central processing unit CPU. Similarly, the output voltages of the UV energy sensor, temperature sensor, and LED constant voltage source are all connected to the ADC input pin of the central processing unit CPU through analog circuits. The central processing unit CPU monitors the above analog quantities in real time. When an abnormality occurs, the output of the LED constant voltage source and the output of the DIM pin are immediately turned off. When the given current of the LED light string decreases, the central processing unit CPU detects that the voltage of the power tube drain increases, and will reduce the output voltage of the LED constant voltage source through DAC or communication to ensure that the voltage difference on the power tube is maintained at a lower value to improve circuit efficiency.

[0088] When the ultraviolet light power output by the LED decreases due to external factors or aging of the LED lamp beads, the ultraviolet energy sensor S1 collects the real-time ultraviolet light power signal of the LED to the central processing unit CPU, and the central processing unit CPU inputs the ultraviolet light power error signal (i.e., the difference between the ultraviolet light power detection signal and the ultraviolet light power given signal) into the PID controller of the ultraviolet light power loop in the control unit. The PID controller outputs the calculation result to the constant current PID controller, which eventually causes the current of the LED lamp string to increase and the ultraviolet light power to increase until it is consistent with the given value, thereby finally achieving constant ultraviolet light power control.

[0089] This embodiment also provides an electronic device, including the multi-channel light emitting diode constant current constant light power driving circuit of any of the above embodiments.

[0090] It can be understood that the contents of the above circuit embodiments are all applicable to the electronic device embodiment, the functions specifically implemented by the electronic device embodiment are the same as those of the above circuit embodiments, and the beneficial effects achieved are also the same as those achieved by the above circuit embodiments.

[0091] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, device, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. It should be understood that in the present application, "at least one (item)" refers to one or more, and "a plurality" refers to two or more.

[0092] In the several embodiments provided in the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0093] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0094] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0095] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the circuit described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, referred to as ROM), random access memory (Random Access Memory, referred to as RAM), disk or optical disk and other media that can store program codes.

[0096] Although the description of the present application has been quite detailed and specifically describes several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, but should be regarded as providing a broad possible interpretation of these claims by reference to the attached claims, taking into account the prior art, so as to effectively cover the intended scope of the present application. In addition, the above description of the present application is based on the embodiments foreseeable by the inventor, and its purpose is to provide a useful description, and those non-substantial changes to the present application that have not yet been foreseen may still represent equivalent changes to the present application.

Claims

1. A constant current and constant light power driving circuit for multiple light emitting diodes, characterized in that: The circuit includes a power supply unit, a light emitting unit, a power tube unit and a control unit; The power supply unit is connected to the light emitting unit and is used to transmit a voltage signal to the light emitting unit; The power tube unit is connected to the light-emitting unit and is used to adjust the current of the light-emitting unit to control the light-emitting unit to be in a constant current state; The control unit is connected to the power supply unit and the power tube unit respectively, and is used to monitor the power tube unit and adjust the voltage signal through the power supply unit according to the monitored signal to control the voltage value of the power tube unit to be within the first target value range.

2. The multi-channel light emitting diode constant current constant light power driving circuit according to claim 1, characterized in that: The control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and issue an alarm notification of power tube unit abnormality when it is detected that the voltage value of the power tube unit is within a first abnormal value range.

3. The constant current and constant light power driving circuit for multiple light emitting diodes according to claim 1, characterized in that: The circuit further comprises a first sensor unit; The first sensor unit is connected to the control unit and is used to collect the temperature value of the light-emitting unit and transmit it to the control unit; The control unit is used to adjust the voltage signal through the power supply unit based on the power tube voltage drop value detected from the power tube unit and the temperature value, so as to control the voltage value of the power tube unit to be within a second target value range; The control unit is also used to control the power supply unit to stop outputting the voltage signal, control the power tube unit to be in a current cutoff state, and issue an alarm notification of abnormal light emitting unit temperature when it is detected that the temperature value of the light emitting unit is within a second abnormal value range.

4. The multi-channel light emitting diode constant current constant light power driving circuit according to claim 1, characterized in that: The control unit is also used to save the power tube pressure difference value monitored by the power tube unit as a historical pressure difference value; The control unit is further used to determine the difference between the current power tube pressure difference value and the historical pressure difference value, and to issue an alarm notification when the difference is greater than a preset difference.

5. The constant current and constant light power driving circuit for multiple light emitting diodes according to claim 1, characterized in that: The circuit further comprises a second sensor unit; The second sensor unit is connected to the control unit and is used to collect the ultraviolet light power signal of the light emitting unit and transmit it to the control unit; The control unit is used to compare the ultraviolet light power signal with a preset ultraviolet light power given signal to obtain an ultraviolet light power error value, and send adjustment signals to the power tube unit and the power supply unit respectively according to the ultraviolet light power error value to control the ultraviolet light power value of the light-emitting unit to be equal to a preset threshold value; The power tube unit is used to adjust the current of the light-emitting unit when the adjustment signal is obtained; The power supply unit is used to adjust the voltage signal transmitted to the light emitting unit when the adjustment signal is acquired.

6. The constant current and constant light power driving circuit for multiple light emitting diodes according to claim 5, characterized in that: The circuit comprises a plurality of the light-emitting units and a plurality of the power tube units; each of the light-emitting units is connected to one of the power tube units to form a plurality of integrated light-emitting units; The power supply unit is respectively connected to the light-emitting units in each of the integrated light-emitting units, and transmits the same parallel voltage signal to each of the integrated light-emitting units; The control unit is respectively connected to the power tube unit in each of the integrated light-emitting units, and is used to adjust the parallel voltage signal through the power supply unit according to the signal monitored from the target integrated light-emitting unit among the multiple integrated light-emitting units, so as to control the voltage value of the power tube unit in each of the integrated light-emitting units to be within a third target value range.

7. The constant current and constant light power driving circuit for multiple light emitting diodes according to claim 6, characterized in that: The circuit further comprises a plurality of the second sensor units; each light emitting unit of the integrated light emitting unit corresponds to one of the second sensor units; The power supply unit comprises a plurality of power switch modules, each of which is connected to one of the integrated light emitting units; Each of the second sensor units is used to collect the ultraviolet light power signal of the target light-emitting unit according to the corresponding relationship and transmit it to the control unit to determine the light power corresponding to each of the integrated light-emitting units; The power supply unit is further used to adjust the current transmitted to each of the integrated light-emitting units through each of the switch modules, until the optical power corresponding to each of the integrated light-emitting units is equal to the corresponding target optical power.

8. The multi-channel light emitting diode constant current constant light power driving circuit according to any one of claims 1 to 7, characterized in that: The power tube unit includes a power tube module and a negative feedback regulation module; The first end of the power tube module is used to connect the light-emitting unit, the second end of the power tube module is connected to the second input end of the negative feedback regulation module, and the third end of the power tube module is connected to the output end of the negative feedback regulation module; The first input terminal of the negative feedback regulation module is connected to the first control signal output terminal of the control unit.

9. The constant current and constant light power driving circuit for multiple light emitting diodes according to claim 8, characterized in that: The power tube module includes a power tube, a first resistor, a second resistor and a third resistor; The first end of the power tube serves as the first end of the power tube module, the second end of the power tube serves as the second end of the power tube module, and the third end of the power tube serves as the third end of the power tube module; One end of the first resistor is connected to the first end of the power tube, and the other end of the first resistor is connected to the first sampling signal input end of the control unit; One end of the second resistor is connected to the other end of the first resistor, and the other end of the second resistor is connected to the negative output end of the power supply unit; One end of the third resistor is connected to the second end of the power tube, and the other end of the third resistor is connected to the negative output end of the power supply unit.

10. The multi-channel light emitting diode constant current constant light power driving circuit according to any one of claims 1 to 7, characterized in that: The sampling signal output terminal of the power supply unit is connected to the second sampling signal input terminal of the control unit, and the control signal input terminal of the power supply unit is connected to the second control signal output terminal of the control unit; The control unit is used to obtain a power sampling signal through the second sampling signal input terminal of the control unit, generate a power control signal according to the power sampling signal, and transmit the power control signal to the power supply unit through the second control signal output terminal of the control unit.

11. An electronic device, characterized in that: It comprises the constant current and constant light power driving circuit for multiple light emitting diodes as described in any one of claims 1 to 10.

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