阅读说明：本技术 免电压侦测之快速启动系统 (Fast start system without voltage detection ) 是由 杨世学 林义雄 于 2019-08-09 设计创作，主要内容包括：本发明提供一种免电压侦测之快速启动系统,包括一驱动电路、一电流控制开关、以及一控制器。该驱动电路馈入电流至负载以及对应该负载设置的滤波电容。该电流控制开关连接至该驱动电路的输出,经由接收到的讯号启闭回路以控制该负载以及该滤波电容的输入功率。该控制器系连接至该电流控制开关,该控制器系记录前次电容放电相关性参数,以获取到达LED工作电压参数的等效充电期间,并依据该等效充电期间传送控制讯号至该电流控制开关以切换该负载以及该滤波电容的该输入功率。(The present invention provides a fast start system without voltage detection, which comprises a driving circuit, a current control switch, and a controller. The driving circuit feeds current to a load and a filter capacitor arranged corresponding to the load. The current control switch is connected to the output of the driving circuit, and controls the load and the input power of the filter capacitor through a received signal start-stop loop. The controller is connected to the current control switch, records the discharge related parameters of the previous capacitor to obtain the equivalent charging period of the working voltage parameters of the LED, and transmits a control signal to the current control switch according to the equivalent charging period to switch the load and the input power of the filter capacitor.)

1. A voltage detection-free fast start system is characterized in that it comprises:

a driving circuit for feeding current to the load and a filter capacitor corresponding to the load;

a current control switch connected to the output of the drive circuit, and controlling the input power of the load and the filter capacitor by opening and closing a loop through a received signal; and

a controller connected to the current control switch for recording the related parameters of the previous capacitor discharge to obtain the equivalent charging period of the working voltage parameters of the LED, and transmitting a control signal to the current control switch to switch the load and the input power of the filter capacitor according to the equivalent charging period.

2. The system of claim 1, wherein the controller transmits a first control signal to the current control switch to output a high power charging current to charge the filter capacitor during the equivalent charging period, and transmits a second control signal to the current control switch to switch the output to a normal charging current to normally power the load and the filter capacitor after the equivalent charging period.

3. The voltage-detection-free fast start system as claimed in claim 1, wherein the current control switch is connected to a constant current source.

4. The voltage detection-free fast start system as claimed in claim 3, wherein the controller obtains the equivalent charging period according to the following calculation formula:

wherein T is the equivalent charging period, M is the capacitor discharge correlation parameter, V_CIs the LED barrier voltage, X is the charge end point ratio, I_inFor charging current, I_LThe constant current source is a current, and C is a capacitance value of a capacitor.

5. The voltage detection-free fast start system as claimed in claim 1, wherein the current control switch is loaded with a resistor on its loop.

6. The voltage detection-free fast start system as claimed in claim 5, wherein the controller obtains the equivalent charging period according to the following calculation formula:

wherein, T is an equivalent charging period, M is a capacitor discharge correlation parameter, VC is an LED barrier voltage, X is a charging terminal point proportion, Iin is a charging current, C is a capacitor capacitance value, and R is a resistance value.

7. A fast start method without voltage detection is disclosed, which is characterized in that it comprises:

the controller records the discharge correlation parameter of the previous filter capacitor;

the controller obtains an equivalent charging period reaching the termination working parameter of the filter capacitor according to the capacitor discharge correlation parameter; and

the controller transmits a control signal to the current control switch according to the equivalent charging period to switch the input power of the driving circuit to the load and the filter capacitor.

8. The voltage detection-free fast start-up method as claimed in claim 7,

the controller transmits a first control signal to the current control switch during the equivalent charging period to output a high-power charging current to charge the filter capacitor;

the controller transmits a second control signal to the current control switch after the equivalent charging period so as to switch and output the current control switch into a conventional charging current to supply power to the load and the filter capacitor conventionally.

9. The voltage detection-free fast start method as claimed in claim 7, wherein the controller obtains the equivalent charging period according to the following calculation formula:

wherein T is the equivalent charging period, M is the capacitor discharge correlation parameter, V_CIs the LED barrier voltage, X is the charge end point ratio, Iin is the charge current, I_LThe constant current source is a current, and C is a capacitance value of a capacitor.

10. The voltage detection-free fast start method as claimed in claim 7, wherein the controller obtains the equivalent charging period according to the following calculation formula:

wherein T is the equivalent charging period, M is the capacitor discharge correlation parameter, V_CThe voltage of the LED barrier is shown, X is the charging end point proportion, Iin is the charging current, C is the capacitance value of the capacitor, and R is the resistance value of the resistor.

Technical Field

The present invention relates to a fast start system of LED, and more particularly to a fast start system without voltage detection.

Background

With the development of the technology and the breakthrough of the white light LED technology, the LED has been widely used in various household lighting devices nowadays. Since the led lamp itself is a high-performance illumination light source, it is gradually replacing the traditional incandescent lamp and fluorescent lamp in recent years, and becomes the mainstream of the illumination market.

In order to improve the output stability of the light emitting diode, a large capacitor is mounted on an output stage of a driving circuit of the light emitting diode at present, and if the output is in a low dimming (low current) state, the LED lamp is turned on only within an excessively long time due to the excessively long charging time of the capacitor, so that a user misjudges whether the LED lamp can normally work. However, this problem is mainly caused by the operating voltage characteristic of the LED, and when the capacitor charging voltage does not reach the operating voltage of the LED, the LED lamp is over-charged but the voltage is insufficient and still stays in the cut-off region of the LED lamp, so that the LED cannot be turned on.

Disclosure of Invention

The main objective of the present invention is to provide a voltage-detection-free fast start system, which includes a driving circuit, a current control switch, and a controller. The driving circuit feeds current to a load and a filter capacitor arranged corresponding to the load. The current control switch is connected to the output of the driving circuit, and controls the load and the input power of the filter capacitor through a received signal start-stop loop. The controller is connected to the current control switch, records the discharge related parameters of the previous capacitor to obtain the equivalent charging period of the working voltage parameters of the LED, and transmits a control signal to the current control switch according to the equivalent charging period to switch the load and the input power of the filter capacitor.

Another objective of the present invention is to provide a voltage detection-free fast start method, which comprises: the controller records the related parameters of the previous capacitor discharge; the controller obtains an equivalent charging period of the LED working voltage parameter according to the capacitor discharge correlation parameter; and the controller transmits a control signal to the current control switch according to the equivalent charging period so as to switch the input power of the driving circuit to the load and the filter capacitor.

Therefore, the present invention has the following technical effects compared with the prior art:

1. the system and the method provided by the invention can rapidly charge the filter capacitor when the optical drive circuit is switched from off to on so as to achieve the effect of rapidly starting the lamp source in a low dimming state.

2. The invention can reduce the pin position needed by IC (such as controller) because it doesn't need reading voltage, it doesn't need voltage dividing resistance, it doesn't have normal state loss, so the standby power consumption is lower, and the circuit is simpler.

Drawings

FIG. 1 is a schematic diagram of a voltage detection-free fast start system according to the present invention.

Fig. 2 is a schematic diagram of a high-speed discharge module according to the present invention.

Fig. 3 is a circuit diagram of the first embodiment of the present invention.

FIG. 4 is a circuit diagram illustrating a second embodiment of the present invention.

FIG. 5 is a flow chart of the fast start method without voltage detection according to the present invention.

100, quickly starting a system; 10 a drive circuit; 20 current control switches; 30 a high-speed discharge module; 31 a first controller; 32 a second controller; 33 a logic gate; 34 a counter; 35 a discharge cell; 40 a controller; a 50 load; a CF filter capacitor; a1 constant current source; r1 fixed resistance; steps S01-S03

Detailed Description

The detailed description and technical contents of the present invention will be described below with reference to the accompanying drawings. Furthermore, for convenience of illustration, the drawings are not necessarily drawn to scale, and they are not intended to limit the scope of the invention.

Please refer to fig. 1, which is a schematic diagram of the voltage detection-free fast start system of the present invention, and is shown in the figure:

the voltage detection-free fast start system 100 of the present invention is mainly configured on an LED lighting device, and is used for driving an LED at a high speed to reach an LED operating voltage in a short time. The voltage detection-free fast start system 100 mainly includes a driving circuit 10, a current control switch 20, a high-speed discharge module 30, and a controller 40 connected to the driving circuit 10, the current control switch 20, and the high-speed discharge module 30.

The driving circuit 10 feeds a current to the load 50 and a filter capacitor CF corresponding to the load 50(LED) to charge the filter capacitor CF and supply power required for the operation of the load 50. The driving circuit 10 may include a power supply (which may be an ac power supply or a dc power supply), a transformer, a rectifier, a filter, or other similar circuits or devices in one embodiment, which is not limited in the invention.

The current control switch 20 is connected to the output of the driving circuit 10, and controls the input power of the load 50 and the filter capacitor CF by turning on and off the loop via the signal received by the controller 40. Specifically, the current control switch 20 can control the period and frequency of the switch by using pulse modulation (PWM) as an input to determine the output power to the load 50 and the filter capacitor CF.

The high-speed discharging module 30 is connected to the load 50 and the filter capacitor CF, and the high-speed discharging module 30 can rapidly switch the loop of the load 50 to the ground, so as to linearly discharge and output the energy of the filter capacitor CF through the design of the constant-current dummy load, thereby reducing the discharging time. The high-speed discharge module will be described in detail later.

The controller 40 is connected to the driving circuit 10, the current control switch 20, and the high-speed discharging module 30 to control the operations of the circuits and modules. The controller 40 may be, for example but not limited to, a Central Processing Unit (CPU), or other programmable general purpose or special purpose Microprocessor (Microprocessor), Digital Signal Processor (DSP), Application Specific Integrated Circuit (ASIC), or other similar devices or combinations thereof. In one embodiment, the controller may be configured with the storage unit or be integrated with the storage unit as a single chip for permanently or semi-permanently storing a part of the information (e.g., a lookup table or operating parameters) so as to access the relevant operating parameters for the next execution. The controller 40 records the discharge related parameters of the previous high-speed discharge module 30 through the filter capacitor CF to obtain an equivalent charge period that breaks through the operating voltage parameters of the LED (load 50), and transmits a control signal to the current control switch 20 according to the equivalent charge period to switch the load 50 and the input power of the filter capacitor CF. In the control logic, when the controller 40 transmits a first control signal to the current control switch 20 during the equivalent charging period to output a high power charging current to charge the filter capacitor CF, and transmits a second control signal to the current control switch 20 after the equivalent charging period to switch the output to a normal charging current to normally power the load and the filter capacitor CF.

The specific calculation will be described in detail later.

Please refer to fig. 2, which is a schematic diagram of a high-speed discharge module according to the present invention, and the diagram is shown:

the high-speed discharging module 30 mainly includes a first controller 31 connected to the output of the driving circuit 10, a second controller 32 connected to the output of the filter capacitor CF, a logic gate 33 connected to the first controller 31 and the second controller 32, a counter 34 disposed between the first controller 31 and the logic gate 33, and a discharging unit 35 connected in parallel to the load 50. It should be specifically noted that the first controller 31 and the second controller 32 can be implemented as separate single chips, or can be configured together or as a single chip with the controller 40, and the present invention is not limited thereto. The logic Gate 33 may be an AND Gate (AND Gate), an OR Gate (OR Gate), a NAND Gate (NAND Gate), a NOR Gate (NOR Gate), etc., AND the type of the logic Gate 34 may be modified by modifying the circuit design (e.g., increasing the number of logic gates, the inverter, modifying the trigger condition of the counter, etc.) according to the actual configuration, which is not intended to limit the scope of the present invention.

When the driving circuit 10 is over-current (the switch is turned on), the first controller 31 compares the voltage of the driving circuit 10 with a default voltage level, when the voltage of the driving circuit 10 is greater than the default voltage level in the start-up state, the first controller 31 outputs a high level voltage, and the output high level voltage is oscillated to the high level through the schmitt trigger and is output to the counter 34. When receiving the high level output, the counter 34 continuously resets the count and outputs the first logic parameter to the first input of the logic gate 33, and at this time, the second controller 32 outputs a second logic parameter to the second input of the logic gate 33 because the filter capacitor CF is charged to the high level, and outputs a control signal to the discharge unit 35 through the logic gate 33 to keep the discharge unit 35 in an open state. At this time, the output of the driving circuit 10 is over-current to the filter capacitor CF and the load 50.

At the moment when the circuit switch is turned off, the first controller 31 compares the output voltage of the driving circuit 10 with the default voltage level, and since the output voltage is smaller than the default voltage level when the driving circuit 10 is in the off state, the first controller 31 outputs the low level voltage, and the output low level voltage is oscillated to the low level through the schmitt trigger and is output to the counter 34. At this time, since the reset pin of the counter 34 is changed from the high level to the low level, the counter 34 will continuously superimpose the output value according to the frequency, and when the output value reaches the set value, the counter 34 will output the third logic parameter to the first input of the logic gate 33. The above circuit is performed simultaneously, since the energy of the filter capacitor CF is not released during counting, the second controller 32 keeps outputting the second logic parameter because the filter capacitor CF is charged to the high level and the output is still the high level voltage, at this time, the logic gate 33 outputs another control signal to the discharging unit 35 to turn on (ground) the discharging unit, and the energy of the filter capacitor CF is guided to the ground until the energy of the filter capacitor is released to the low level.

The value of the counter 34 at the final stack is stored in the storage unit as the parameter related to the discharge of the capacitor. Based on the capacitor discharge correlation parameter, the controller can estimate the charging time required by the filter capacitor CF without retrieving voltage feedback. Based on the capacitor discharge correlation parameter, the calculation formula can be adjusted according to different circuit designs, and two different embodiments of the present invention are described below:

please refer to fig. 3, which is a circuit diagram illustrating a first embodiment of the present invention, as shown in the figure:

in a possible embodiment, in the embodiment of mounting the constant current source a1 on the loop of the current control switch 20, the following parameters can be confirmed after the first discharge is completed: capacitor discharge phaseCritical parameterWherein S_thIs the final superimposed value of the counter in the discharge state, F_swIs the power switching frequency; on circuit environment settings, the following parameters are determinable: v_CIs the LED barrier voltage, X is the charge end point ratio, I_inFor charging current, I_LThe current of the constant current source is C, and the capacitance value of the filter capacitor is C.

In the initial calculation, the end point voltage V of the charging must be determined_targetI.e. the target voltage at which the filter capacitor CF reaches the operating state. V_targetCan be obtained by the following calculation:

V_target＝V_C×X

then, a capacitor discharge dependency parameter is calculated, defined as the time T for the filter capacitor CF to discharge below the LED barrier voltage_Ron。T_RonCan be obtained by the following calculation:

wherein T is_RonOther characteristic parameters can be substituted, not limited by the above formula; then calculating the capacitor charge T_RonVoltage V of_C，TRon。V_C，TRonCan be obtained by the following calculation:

then calculate T_RonVoltage V of_C，TRonCharging to the end point voltage V_targetRequired time T_Roff：

Summarizing the above calculations, it is finally deduced that the equivalent charging period T can be obtained by the following equation:

thereby, the charging time required for the filter capacitor CF can be obtained finally.

Please refer to fig. 4, which is a circuit diagram illustrating a second embodiment of the present invention, as shown in the figure:

in another possible embodiment, in the embodiment of mounting the constant resistor R1 on the loop of the current control switch 20, the following parameters can be confirmed after the first discharge is completed: capacitance discharge dependent parameterWherein S_thIs the final superimposed value of the counter in the discharge state, F_SWIs the power switching frequency; on circuit environment settings, the following parameters are determinable: v_CIs the LED barrier voltage, X is the charge end point ratio, I_inIs the charging current, and C is the capacitance value of the filter capacitor.

In the initial calculation, the end point voltage V of the charging must be determined_targetI.e. the target voltage at which the filter capacitor CF reaches the operating state. V_targetCan be obtained by the following calculation:

V_target＝V_C×X

then, a capacitor discharge dependency parameter is calculated, defined as the time T for the filter capacitor CF to discharge below the LED barrier voltage_Ron。T_RonCan be obtained by the following calculation:

same as above, T_RonOther characteristic parameters can be substituted, not limited by the above formula; then calculating the capacitor charge T_RonVoltage V of_C，TRon。V_C，TRonCan be obtained by the following calculation:

then calculate T_RonVoltage V of_C，TRonCharging to the end point voltage V_targetRequired time T_Roff：

Summarizing the above calculations, it is finally deduced that the equivalent charging period T can be obtained by the following equation:

based on the above equations of the first and second embodiments, the controller 40 can calculate the charging time of the filter capacitor CF without voltage feedback. Based on that the charging time controller 40 can operate in two different power supply modes, the filter capacitor CF is charged with a high power charging current during the equivalent charging period, and is switched to a normal charging current after the equivalent charging period elapses to normally supply power to the load and the filter capacitor CF, thereby achieving the effect of fast LED start.

In another embodiment of the present invention, a fast start method is provided in conjunction with the above circuit architecture, and is correspondingly disposed on a driving system of an LED. Referring to fig. 5, a flow chart of the fast start method without voltage detection according to the present invention is illustrated as follows:

the fast boot method of the present invention can be implemented as software or firmware installed in a processor and executed by the processor, or directly implemented by a plurality of chips and circuits, which are not intended to limit the scope of the present invention. The method comprises the following steps:

the controller 40 records the capacitor discharge correlation parameter when the power is turned off last time (step S01); the capacitor discharge correlation parameter may be the discharge time of the filter capacitor CF, the number of times of the counter, or any other parameter having a positive correlation with the discharge time of the filter capacitor CF, which is not limited in the present invention.

The controller 40 obtains an equivalent charging period reaching the termination operating parameter of the filter capacitor CF according to the capacitor discharge correlation parameter of the filter capacitor (step S02); the equivalent charging period may be slightly different in calculation manner according to different types of circuits, and the emphasis in the present application is to obtain the equivalent charging period of the filter capacitor CF terminating operation parameter by recording the capacitor discharge correlation parameter, and the formula described in the above embodiment is only used as an example and is not used to limit the scope of the present invention.

The controller 40 transmits a control signal to the current control switch according to the equivalent charging period to switch the input power of the driving circuit 10 to the load and the filter capacitor CF (step S03); in step S03, the controller 40 switches between two different power supply modes; during the equivalent charging period, the controller 40 transmits a first control signal to the current control switch 20 to output a high power charging current to charge the filter capacitor CF; the controller 40 transmits a second control signal to the current control switch 20 after the equivalent charging period to switch the output to the normal charging current for the normal power supply of the load and the filter capacitor. Based on the above switching mode, the present invention can charge the filter capacitor CF to the working voltage in a relatively short time, so as to achieve the effect of fast lighting.

In summary, the system and method provided by the present invention can rapidly charge the filter capacitor when the optical drive circuit is turned on from off, so as to achieve the effect of rapidly starting the light source in a low dimming state. In addition, the invention does not need to read voltage, can reduce pins required by an IC (such as a controller), does not need a divider resistor, does not have normal loss, has lower standby power consumption and simpler circuit.

Although the present invention has been described in detail, it should be understood that the above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the invention, i.e., the appended claims are intended to cover all such modifications and changes as fall within the true spirit and scope of the invention.