CN110418449A - Drive circuit device for automatically detecting line lights and optimizing drive voltage - Google Patents

Abstract

A driving circuit device for automatically detecting the optimal driving voltage of a line lamp includes a power converter, a reference light source, a mask element, a brightness detection element, a comparison circuit and a controller. The power converter outputs a driving voltage to drive the line lamp to emit light, and the driving voltage is continuously increased from a starting value to a maximum value, and stops increasing the fixed driving voltage according to an interrupt signal. One end of the reference light source is electrically connected to the line lamp, and the other end is electrically grounded. The mask element has a light-proof chamber, and the reference light source is disposed in the chamber. The brightness detection element is disposed in the chamber and feeds back a brightness signal related to the light intensity. The comparison circuit receives the brightness signal and compares whether the intensity of the brightness signal is greater than the intensity of the reference signal. When the intensity of the brightness signal is greater than the intensity of the reference signal, the controller sends an interrupt signal to the power converter, and the power converter outputs a fixed driving voltage.

Description

Drive circuit device for automatically detecting line lights and optimizing drive voltage

technical field

The present invention relates to a driving circuit of a line lamp, in particular to a driving circuit device for automatically detecting the optimum driving voltage of a line lamp.

Background technique

A line lamp is a long-line lighting device formed by connecting multiple light sources (such as light-emitting diodes and small light bulbs) in series, in parallel, or in series/parallel hybrids. The optimal driving voltage for line lights is affected by the number of light sources. Taking simple series connection as an example, if individual light sources are to achieve the same brightness, the long-term light needs a larger driving voltage, and the short-term light needs a smaller driving voltage. Therefore, the driving circuit must match the design of the line light, so that individual light sources can reach the maximum brightness (the maximum current that can be received) allowed by the specification without being burned.

Whether it is assembled in a factory or replaced by consumers themselves, it is necessary to cooperate with the driving circuit and select the correct type of linear light. Otherwise, the driving voltage may be too low and the brightness may be insufficient, or the driving voltage may be too high and the linear light may burn out. And different drive lines also cause inventory preparation management problems for manufacturers or sellers.

Although there are drive circuits capable of outputting multiple voltages, the output voltage of these drive circuits must be correctly switched by the user or assembler through a switch. Once the switch is wrong, the line lamp will burn out quickly after being powered on.

Contents of the invention

The line lamp driving circuit in the prior art needs to be selected according to the specifications of the line light, which leads to technical problems that the line light is prone to insufficient brightness or burnt out.

In order to solve the above technical problems, the present invention proposes a driving circuit device that automatically detects the optimal driving voltage of the line lamp, which is used to output the driving voltage to drive the line lamp to emit light, and automatically detects the multiple light sources of the line lamp to reach the predetermined The driving voltage required by the brightness is characterized by including a power converter, a reference light source, a mask element, a brightness detection element, a comparison circuit and a controller.

The power converter outputs the driving voltage, and the driving voltage is continuously increased from the initial value to the maximum value, and stops increasing the driving voltage according to the interrupt signal to fix the driving voltage. One end of the reference light source is electrically connected to the line lamp, and the other end is electrically grounded. The shielding element has a light-tight cavity, and the reference light source is arranged in the cavity. The brightness detection element is arranged in the chamber, detects the light intensity emitted by the reference light source, and feeds back a brightness signal related to the light intensity. The comparison circuit receives the luminance signal, compares whether the intensity of the luminance signal is greater than that of the reference signal, and outputs the comparison result. The controller is electrically connected to the power converter and the comparison circuit, and when the strength of the luminance signal is greater than the strength of the reference signal, an interrupt signal is sent to the power converter so that the power converter can output a fixed driving voltage.

According to the aforesaid driving circuit device, the problem of insufficient brightness or burnt-out caused by changing the specification of the line lamp due to the fixed output of the driving voltage in the prior art can be avoided.

Preferably, the reference light source has the same specification as that of each light source of the line light.

Preferably, the shielding element is an opaque tube, the reference light source is arranged at the opening at one end, and the brightness detecting element is arranged at the opening at the other end.

Preferably, when the driving circuit device is activated, the controller sends a start signal to the power converter to start the power converter to start outputting the driving voltage, and continuously increases the driving voltage from the starting value to the maximum value.

Preferably, the brightness detection element is a photoresistor, one end of which receives a standard voltage, and the other end is grounded through a grounding resistor. brightness signal, and the reference signal is a reference voltage.

Preferably, the comparison circuit includes a comparator, which compares the voltage of the brightness signal and the reference voltage, and outputs a high level when the voltage of the brightness signal and the reference voltage is greater than the reference voltage to trigger the controller to send the interrupt signal.

Preferably, the drive circuit device also includes an auxiliary comparator, which is arranged in parallel with the comparator; the auxiliary comparator receives the brightness signal, and compares whether the intensity of the brightness signal is greater than the intensity of the upper limit signal, and outputs a warning result, when the intensity of the brightness signal is greater than the upper limit Signal strength, the controller re-controls the power converter to increase the driving voltage from the initial value to the maximum value and receives the comparison result of the comparator.

Preferably, the drive circuit device further includes a switch element, the reference light source passes through the switch element, and the controller continuously outputs a switching signal, so that the switch element is quickly switched between on and off.

Preferably, the driving circuit device further includes a memory unit, wherein, each time the driving circuit device is started, the controller checks whether the memory unit stores the value of the driving voltage; if so, the controller uses the value of the driving voltage stored in the memory unit, Control the power converter to output the driving voltage with a numerical value instead of detecting the driving voltage; if not, the controller controls the power converter to increase the driving voltage from the initial value to the maximum value, and receives the comparison result of the comparator.

Preferably, the driving circuit device further includes a reset switch, electrically connected to the controller, for resetting the memory unit, so that the controller re-controls the power converter to increase the driving voltage from the initial value to the maximum value, and receives the comparison device comparison results.

According to the aforementioned driving circuit device, when replacing or installing the linear lamp, the user does not need to understand the difference in specifications of the linear lamp, but can directly connect the linear lamp to the driving circuit device. The drive circuit device can automatically detect the drive voltage required to drive the line lamp to reach the maximum brightness without burning out, and continuously drive the line lamp to emit light with the drive voltage. In addition, in one or more embodiments of the present invention, the controller can restart the driving voltage detection process periodically, by being reset or according to real-time detection, so that the value of the driving voltage can match the change of the actual situation of the line lamp And change to obtain the best driving voltage.

Description of drawings

Accompanying drawing 1 is the circuit block diagram of the first embodiment of the present invention.

Accompanying drawing 2 is the circuit diagram of the second embodiment of the present invention.

Accompanying drawing 3 is the circuit diagram of the third embodiment of the present invention.

Accompanying drawing 4 is the circuit diagram of the fourth embodiment of the present invention.

Explanation of reference signs

100 drive circuit device; 110 power converter;

120 reference light source; 130 masking element;

140 brightness detection element; 142 grounding resistance;

150 comparison circuits; 152 comparators;

154 amplifiers; 156 auxiliary comparators;

160 controllers; 162 switching elements;

164 memory units; 166 reset switches;

200 line lights; 210 light sources;

Ve external power; Vdd drive voltage;

Vref reference voltage; Vs standard voltage;

Vmax upper limit voltage.

Detailed ways

Please refer to FIG. 1 , which is a driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of line lights disclosed in the first embodiment of the present invention, and is used to automatically detect multiple light sources for line lights 200 210 reaches the magnitude of the driving voltage Vdd required for a predetermined brightness, so as to automatically switch the output driving voltage Vdd. The driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of line lamps includes a power converter 110, a reference light source 120, a mask element 130, a brightness detection element 140, a comparison circuit 150 and a controller 160 .

As shown in FIG. 1 , the power converter 110 is used to receive an external power Ve and convert it into a driving voltage Vdd, and can change the magnitude of the driving voltage Vdd according to a control signal or automatically, so that the driving voltage Vdd is continuously increased from an initial value to a maximum value, and stop raising the driving voltage Vdd according to an interrupt signal, so as to fix the magnitude of the driving voltage Vdd. One terminal of the line lamp 200 to be driven is electrically connected to the power converter 110 through a power output port, and receives the driving voltage Vdd. In most power converters 110 for driving the line lights 200, the driving voltage Vdd can be switched between 0V and 29V.

The line light 200 has multiple light sources 210 connected in series, in parallel or in series/parallel; the light sources 210 can be light emitting diodes or other small bulbs. The power output port can be a socket, and the input end of the line light 200 is provided with a plug, and the plug can be quickly plugged into the socket, so as to facilitate the connection or removal of the line light 200 .

As shown in Figure 1, one end of the reference light source 120 is electrically connected to the line lamp 200, and the other end is electrically grounded. The line lamp 200 and the reference light source 120 can form a complete loop from the output end of the driving voltage Vdd to the ground, so that the line lamp 200 , the reference light source 120 is driven by the driving voltage Vdd to emit light, and the brightness of the reference light source 120 will vary with the resistance of the line lamp 200 . Generally speaking, the reference light source 120 can be of the same specification as the light source 210 of the line lamp 200 , so as to facilitate the comparison condition setting of the comparison circuit 150 .

The shielding element 130 has a light-tight chamber, and the reference light source 120 is disposed in the chamber of the shielding element 130, so that the light emitted by the reference light source 120 will not leak out. Generally speaking, the mask element 130 can be an opaque tube (such as a black tube), the reference light source 120 is disposed at an opening at one end, and the reference light source 120 is fixed and sealed with an opaque material.

The brightness detection element 140 may be a combination of a photoresistor and necessary circuits, or other photoelectric elements capable of detecting brightness. The brightness detection element 140 is also arranged in the cavity of the mask element 130, so that the brightness detection element 140 will not be affected by external light, and detects a light intensity emitted by the reference light source 120, and feeds back a light intensity related to the light intensity. Brightness signal; the form of the brightness signal depends on the configuration of the brightness detection element 140 . When the shielding element 130 is an opaque tube, the brightness detecting element 140 is disposed at the opening at the other end, and the brightness detecting element 140 is fixed and sealed with an opaque material.

The comparison circuit 150 is connected to the brightness detection element 140 for receiving the brightness signal, and compares whether the strength of the brightness signal is greater than the strength of a reference signal, and outputs a comparison result.

The controller 160 is electrically connected to the comparison circuit 150 and the power converter 110 . The controller 160 can send a starting signal to the power converter 110 when the driving circuit device 100 starts up, so as to start the power converter 110 to start outputting the driving voltage Vdd, and continuously increase the driving voltage Vdd from the starting value to the maximum value. The controller 160 continues to receive the comparison result of the comparison circuit, and sends an interrupt signal to the power converter 110 when the intensity of the brightness signal is greater than a reference signal, so that the power converter 110 outputs a fixed driving voltage Vdd.

As shown in FIG. 1, when the line lamp 200 is connected to the driving circuit device 100, and the driving circuit device 100 is started, the line lamp 200 and the reference light source 120 will be driven by the driving voltage Vdd to emit light, and as the driving voltage Vdd increases Gradually increase brightness. When the light sources 210 of the line light 200 are arranged in series, the reference light source 120 and each light source 210 of the line light 200 will have the same brightness. When the light sources 210 of the line light 200 are mixed in series and parallel, there will also be a certain proportional relationship between the brightness of the reference light source 120 and each light source 210 of the line light 200; therefore, the brightness of the line light 120 can be used to obtain the line The brightness of each light source 210 of the lamp 200 .

At this time, the brightness detection element 140 can detect the brightness of the reference light source 120, and compare whether the intensity of the brightness signal is greater than the intensity of the reference signal, and output a comparison result. The intensity of this reference signal corresponds to the optimum brightness of each light source 210 of the line lamp 200 and will not cause the intensity of each light source 210 of the line lamp 200 to burn out due to too high driving voltage Vdd. If the intensity of the brightness signal is not greater than the intensity of the reference signal, it means that the brightness of the light source 210 is still insufficient. If the strength of the brightness signal is greater than the strength of the reference signal, the brightness of the light source 210 has reached the optimum brightness, and if the driving voltage Vdd is further increased, the light source 210 will be burned; at this time, the controller 160 can send an interrupt signal to The power converter 110 stops the power converter 110 from boosting the driving voltage Vdd, and fixes the magnitude of the driving voltage Vdd to drive the line lamp 200 .

According to the driving circuit device 100 mentioned above, the problem of insufficient brightness or burnt-out when the specification of the line lamp 200 is replaced due to the fixed output of the driving voltage Vdd in the prior art can be avoided. The driving circuit device 100 can automatically detect the optimal driving voltage Vdd, so that the line lamp 200 can reach the maximum brightness without burning out.

As shown in FIG. 2 , the second embodiment of the present invention discloses a driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of the linear lamp, which is used to automatically detect the arrival of multiple light sources 210 of the linear lamp 200. The magnitude of the driving voltage Vdd required by a predetermined brightness, so as to automatically switch the output driving voltage Vdd. The driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of line lights includes a power converter 110 , a reference light source 120 , a masking element 130 , a brightness detecting element 140 , a comparison circuit 150 and a controller 160 . The power converter 110 , the reference light source 120 , the masking element 130 and the controller 160 are substantially the same as those of the first embodiment, and will not be repeated below. Only the details of the brightness detection element 140 and the comparison circuit 150 will be described below.

The brightness detection element 140 is a photoresistor, one end of which receives a standard voltage Vs, and the other end is grounded through a grounding resistor 142 . The resistance of the photoresistor can change the voltage at the connection between the brightness detection element 140 and the grounding resistor 142 as the brightness decreases, as a brightness signal.

The comparison circuit 150 includes a comparator 152 for receiving the luminance signal and comparing the luminance signal with a reference signal. The reference signal is a reference voltage Vref. Both the reference voltage Vref and the standard voltage Vs can be fixed voltage outputs provided by the power converter 110 . An amplifier 154 may be further provided between the comparator 152 and the photoresistor to amplify the brightness signal, thereby adjusting the proportional relationship between the brightness signal and the reference signal, so as to set the optimal brightness of the line lamp 200 .

The increase of the driving voltage Vdd gradually increases the brightness of the light source 210, the resistance of the photoresistor will continue to decrease, and the voltage value of the brightness signal will continue to increase. When the voltage value of the brightness signal is lower than the reference voltage Vref of the reference signal, it means that the brightness of the line lamp 200 has not reached the desired brightness. At this time, the comparison result output by the comparator 152 will maintain a low level, and the controller 160 will not act. When the voltage value of the brightness signal is greater than the reference voltage Vref of the reference signal, it means that the brightness of the line lamp 200 has reached the desired brightness. At this time, the comparison result output by the comparator 152 will become a high level, and the controller 160 will be triggered. The interrupt signal is sent, so that the power converter 110 stops raising the driving voltage Vdd, and the magnitude of the driving voltage Vdd is fixed to drive the line lamp 200 .

In addition, the driving circuit device 100 further includes a switch element 162 , such as a transistor switch. Reference light source 120 is grounded via switching element 162 . The controller 160 continuously outputs a switching signal, so that the switching element 162 can be quickly switched between on and off, so that the driving voltage Vdd can only briefly drive the line lamp 200 to light up during the detection process, and avoid the initial state of the driving voltage. If the value is too high, the line lamp 200 will burn out during the detection process. At the same time, the continuously blinking line light 200 can also let the user know that the driving circuit device 100 is detecting the magnitude of the driving current.

As shown in FIG. 3 , the third embodiment of the present invention discloses a driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of the linear lamp, which is used to automatically detect the arrival of multiple light sources 210 of the linear lamp 200. The magnitude of the driving voltage Vdd required by a predetermined brightness, so as to automatically switch the output driving voltage Vdd. The driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of line lights includes a power converter 110 , a reference light source 120 , a masking element 130 , a brightness detecting element 140 , a comparison circuit 150 and a controller 160 . The difference of the driving circuit device 100 of the third embodiment is that it further includes a memory unit 164 and a reset switch 166 .

In the third embodiment, the memory unit 164 is electrically connected to the controller 160 . When the memory unit 164 does not store the value of the driving voltage Vdd, for example, the driving circuit device 100 is used for the first time, and the memory unit 164 is not preloaded with any value of the driving voltage Vdd, the controller 160 controls the power converter 110 to start from the initial value Gradually increase the driving voltage Vdd to the maximum value. The controller 160 outputs an interrupt signal according to the comparison result of the comparator 152 so that the power converter 110 stops raising the driving voltage Vdd, and fixes the magnitude of the driving voltage Vdd to drive the line lamp 200. The value of the driving voltage Vdd is obtained and stored in the memory unit 164 .

And every time when the driving circuit device 100 is started, the controller 160 first checks whether the memory unit 164 stores the value of the driving voltage Vdd, and if so, the controller 160 uses the value of the driving voltage Vdd stored in the memory unit 164 to directly control the power conversion The device 110 outputs the driving voltage Vdd by a numerical value, and no longer detects the driving voltage Vdd. If not, the controller 160 controls the power converter 110 to gradually increase the driving voltage Vdd from the initial value to the maximum value, and receives the comparison result of the comparator 152 to detect the optimum value of the driving voltage Vdd.

The reset switch 166 is electrically connected to the controller 160 for resetting the memory unit 164, so that the controller 160 re-controls the power converter 110 to gradually increase the driving voltage Vdd from the initial value to the maximum value, and receives the input from the comparator 152 The results are compared to detect the optimum value of the driving voltage Vdd.

Of course, in the foregoing embodiments, since the light source 210 of the line lamp 200 may have brightness decay over time, the controller 160 can regularly re-control the power converter 110 to gradually increase the driving voltage from the initial value to the maximum value. Vdd, and receive the comparison result of the comparator 152, so as to detect the best value of the driving voltage Vdd.

As shown in FIG. 4 , the fourth embodiment of the present invention discloses a driving circuit device 100 for automatically detecting the optimal driving voltage Vdd of the linear lamp, which is used to automatically detect the arrival of multiple light sources 210 of the linear lamp 200. The magnitude of the driving voltage Vdd required by a predetermined brightness, so as to automatically switch the output driving voltage Vdd. The difference between the fourth embodiment and the third embodiment lies in the comparison circuit 150 , and the comparison circuit 150 will be described below.

When the value of the driving voltage Vdd is stored in the memory unit 164 , the controller 160 directly controls the power converter 110 to output the driving voltage Vdd by the value. But at this time, the line lamp 200 may be replaced with a line lamp 200 with a lower resistance value, and the user also forgot to press the reset switch 166 to restart the detection of the driving voltage Vdd.

In the fourth embodiment, in addition to the original comparator 152 , the comparison circuit 150 also includes an auxiliary comparator 156 which is arranged in parallel with the comparator 152 . The auxiliary comparator 156 is also used to receive the luminance signal, and compare whether the intensity of the luminance signal is greater than the intensity of an upper limit signal, and output a warning result, indicating that the intensity of the upper limit signal is greater than the intensity of the reference signal. Sudden partial failure of the line lamp 200 (part of the light source 210 burnt out), cut off, replacement, change of connection mode, etc., will cause the brightness of the reference light source 120 to increase (that is, the current passing through it will increase) when the resistance value drops. The reference signal is an upper limit voltage Vmax, which is greater than the reference voltage Vref. The upper limit voltage Vmax may be a fixed voltage output provided by the power converter 110. The auxiliary comparator 156 can receive the luminance signal directly, or receive the amplified luminance signal through the amplifier 154, so as to adjust the proportional relationship between the luminance signal and the reference signal. The upper limit voltage Vmax mainly corresponds to the upper limit of the brightness that the light source 210 of the line lamp 200 can emit, that is, corresponds to the value of the maximum driving voltage Vdd that the light source 210 can withstand.

When the power converter 110 drives the line lamp 200 with a fixed driving voltage Vdd, the controller 160 continues to receive the warning result. When the intensity (voltage) of the brightness signal is lower than the intensity (upper limit voltage Vmax) of the upper limit signal, the driving voltage Vdd has not yet reached the warning value, and the auxiliary comparator 156 outputs a low level. At this time, the controller 160 does not act. When the intensity of the luminance signal is greater than the intensity of the upper limit signal, the driving voltage Vdd is about to reach the warning value, the auxiliary comparator 156 outputs a high level and triggers the controller 160, the controller 160 restarts the voltage detection, and controls the power converter 110 to start. Gradually increase the driving voltage Vdd from the initial value to the maximum value, and receive the comparison result of the comparator 152, so as to detect the best value of the driving voltage Vdd.

According to the aforementioned driving circuit device 100 , when replacing or installing the linear light 200 , the user does not need to understand the difference in specifications of the linear light 200 , but can directly connect the linear light 200 to the driving circuit device 100 . The driving circuit device 100 can automatically detect that the driving line lamp 200 reaches the maximum brightness without burning out the required driving voltage Vdd, and continuously drive the line lamp 200 to emit light with the driving voltage Vdd. In addition, in one or more embodiments of the present invention, the controller 160 can restart the process of detecting the driving voltage Vdd periodically, by being reset or according to real-time detection, so that the value of the driving voltage Vdd can match the value of the line lamp 200. The actual situation changes to obtain the best driving voltage Vdd.

Claims (10)

1. a kind of driving circuit device of Auto-Sensing line lamp optimization driving voltage, to outputting drive voltage to drive line lamp to send out Light, and Auto-Sensing allows the multiple light sources of the line lamp to reach the driving voltage size required for predetermined luminance, feature It is, includes:

Power adapter exports the driving voltage, and the driving voltage is persistently promoted to maximum value, and foundation by initial value Signal is interrupted to stop promoting the driving voltage and the size of the fixed driving voltage；

Reference light source, one end are electrically connected at the line lamp, other end electrical ground；

Mask element has lighttight chamber, and the reference light source is set in the chamber；

Luminance detection element, setting in the cavity, detect the light intensity that the reference light source issues, and feedback with it is described The relevant luminance signal of light intensity；

Comparison circuit receives the luminance signal, and whether the intensity of the luminance signal is greater than the intensity of reference signal, And export comparison result；And

Controller, is electrically connected at the power adapter and the comparison circuit, and the intensity of Yu Suoshu luminance signal is greater than institute When stating the intensity of reference signal, sending interruption signal to the power adapter, and the power adapter is allowed to fix the drive Dynamic voltage output.

2. driving circuit device according to claim 1, which is characterized in that the reference light source is each with the line lamp Light source same size.

3. driving circuit device according to claim 1, which is characterized in that the mask element is lighttight tube body, The reference light source is set to the opening of one end, and the luminance detection element is set to the opening of the other end.

4. driving circuit device according to claim 1, which is characterized in that the controller is in the driving circuit device When starting, sending start signal to the power adapter starts to export the driving voltage to start the power adapter, And continue to promote the driving voltage by the initial value to the maximum value.

5. driving circuit device according to claim 1, which is characterized in that the luminance detection element is photo resistance, One end receives normal voltage, and the other end is by ground resistance earth, and the resistance value of the photo resistance declines with brightness, and institute State that change the voltage of the junction of luminance detection element and the ground resistance be the luminance signal, and the reference signal For reference voltage.

6. driving circuit device according to claim 5, which is characterized in that the comparison circuit includes comparator, is compared The luminance signal and voltage and the reference voltage, and in the luminance signal and voltage be greater than the reference voltage it is defeated High levle issues the interruption signal to trigger the controller out.

7. driving circuit device according to claim 6, which is characterized in that further include auxiliary comparator, compared with described Device is arranged in parallel；The auxiliary comparator receives the luminance signal, and whether the intensity of the luminance signal is greater than Limit the intensity of signal, output warning result；When the intensity of the luminance signal is greater than the intensity of the upper limit signal, the control Think highly of and newly controls the power adapter driving voltage is promoted by the initial value to the maximum value and receives the ratio Compared with the comparison result of device.

8. driving circuit device according to claim 1, which is characterized in that it further include switch element, the reference light source By the switch element, the controller persistently export switching signal so that the switch element rapidly in conducting with Switch between cutting.

9. driving circuit device according to claim 1, which is characterized in that further include memory unit, driven each time When circuit device starts, the controller checks whether the memory unit stores the numerical value of the driving voltage；

If so, the numerical value for the driving voltage that the controller is stored with the memory unit, controls the power adapter With the numerical value outputting drive voltage, and no longer carry out driving voltage detecting；And

If nothing, the controller controls the power adapter and promotes the driving electricity by the initial value to the maximum value Pressure, and receive the comparison result of the comparator.

10. driving circuit device according to claim 9, which is characterized in that further include Resetting Switching, be electrically connected at institute Controller is stated, to reset the memory unit, so that the controller controls the power adapter by described again Initial value promotes the driving voltage to the maximum value, and receives the comparison result of the comparator.