Projection device, control circuit and control method thereof

Abstract

The invention provides projection equipment, a control circuit and a control method thereof. The control circuit includes a plurality of voltage shifters and an operational circuit. The voltage shifter receives a plurality of selection signals, and shifts peak voltage values of the selection signals to generate a plurality of processed signals. The arithmetic circuit performs a signal decoding action according to the processed signal to generate a plurality of strobe signals. The operational circuits respectively provide gating signals to a plurality of drivers in the driving device so that the drivers respectively generate a plurality of driving signals.

Description

Technical Field

[0001] The invention relates to a projection device, a control circuit and a control method thereof. Background Art

[0002] In a Pico Projector, an Application Specific Integrated Circuit (ASIC) and a Power Management Integrated Circuit (PMIC) are often used to complete the operation of the system. Under such an architecture, the brightness (lumens) that the light-emitting element can produce is limited and cannot provide a higher driving voltage or current. When a laser diode is used as a light-emitting element, the voltage or current provided by the power management chip is often too low, which cannot drive the light-emitting element normally and reduces the performance of the projection device. Summary of the invention

[0003] The invention provides a projection device, a control circuit and a control method thereof, which can expand the number of light-emitting elements and improve the working efficiency of the projection device.

[0004] Based on the above objectives, the present invention proposes a control circuit that drives multiple light-emitting elements through a driving device. The control circuit includes: multiple voltage shifters that respectively receive multiple selection signals and shift the peak voltage values ​​of the multiple selection signals to generate multiple processed signals; and an operation circuit that is coupled to the multiple voltage shifters and performs signal decoding operations according to the multiple processed signals to generate multiple selection signals, wherein the operation circuit respectively provides the multiple selection signals to multiple drivers in the driving device so that the multiple drivers respectively generate multiple driving signals.

[0005] In a preferred embodiment, each of the voltage shifters adjusts the peak voltage of each corresponding selection signal from a first voltage value to a second voltage value, wherein the first voltage value is smaller than the second voltage value.

[0006] In a preferred embodiment, each of the voltage shifters includes: a first resistor having a first end for receiving an operating voltage; a second resistor having a first end for receiving a corresponding selection signal; a transistor having a first end coupled to the second end of the first resistor, a control end of the transistor coupled to the second end of the second resistor, and a second end of the transistor connected to a reference ground terminal; and a third resistor coupled between the second end and the control end of the transistor, wherein the first end of the transistor generates the corresponding processed signal.

[0007] In a preferred embodiment, the operating voltage is greater than the peak voltage of the selection signal.

[0008] In a preferred embodiment, the operation circuit performs the signal decoding operation on the plurality of processed signals by performing a logic operation and generates the plurality of selection signals.

[0009] In a preferred embodiment, the multiple selection signals include a first selection signal and a second selection signal, the operation circuit performs an OR operation on the first processed signal and the second processed signal to generate a first selection signal; the operation circuit performs an AND operation on the first processed signal and the second processed signal to generate a first signal, and the operation circuit performs an AND operation on the first signal and the second processed signal to generate a second selection signal; the operation circuit performs an AND operation on the first signal and the first processed signal to generate a third selection signal, wherein the first processed signal corresponds to the first selection signal, and the second processed signal corresponds to the second selection signal.

[0010] In a preferred embodiment, the operation circuit includes: an NOR gate, which receives the first processed signal and the second processed signal and generates the first selection signal; an NAND gate, which receives the first processed signal and the second processed signal and generates the first signal; a first AND gate, which receives the first signal and the second processed signal and generates the second selection signal; and a second AND gate, which receives the first signal and the first processed signal and generates the third selection signal.

[0011] Based on the above-mentioned purpose, the present invention also proposes a projection device, which includes: a plurality of light-emitting elements; a driving device, which generates a plurality of driving signals according to a plurality of selection signals to drive the plurality of light-emitting elements respectively; and a control circuit, coupled to the driving device, the control circuit including: a plurality of voltage shifters, which respectively receive a plurality of selection signals and shift the peak voltage values ​​of the plurality of selection signals to generate a plurality of processed signals; and an operation circuit, coupled to the plurality of voltage shifters, which performs a signal decoding operation according to the plurality of processed signals to generate the plurality of selection signals.

[0012] In a preferred embodiment, each of the voltage shifters adjusts the peak voltage of each corresponding selection signal from a first voltage value to a second voltage value, wherein the first voltage value is smaller than the second voltage value.

[0013] In a preferred embodiment, each of the voltage shifters includes: a first resistor having a first end for receiving an operating voltage; a second resistor having a first end for receiving a corresponding selection signal; a transistor having a first end coupled to the second end of the first resistor, a control end of the transistor coupled to the second end of the second resistor, and a second end of the transistor connected to a reference ground terminal; and a third resistor coupled between the second end and the control end of the transistor, wherein the first end of the transistor generates a corresponding processed signal.

[0014] In a preferred embodiment, the operating voltage is greater than the peak voltage of the selection signal.

[0015] In a preferred embodiment, the operation circuit performs the signal decoding operation on the plurality of processed signals by performing a logic operation and generates the plurality of selection signals.

[0016] In a preferred embodiment, the multiple selection signals include a first selection signal and a second selection signal, the operation circuit performs an OR operation on the first processed signal and the second processed signal to generate a first selection signal; the operation circuit performs an AND operation on the first processed signal and the second processed signal to generate a first signal, and the operation circuit performs an AND operation on the first signal and the second processed signal to generate a second selection signal; the operation circuit performs an AND operation on the first signal and the first processed signal to generate a third selection signal, wherein the first processed signal corresponds to the first selection signal, and the second processed signal corresponds to the second selection signal.

[0017] In a preferred embodiment, the device further includes: an encoder coupled to the control circuit for providing the plurality of selection signals.

[0018] Based on the above-mentioned purpose, the present invention also proposes a control method for a driving device, which is used to drive multiple light-emitting elements. The characteristic of the control method is that the method includes: providing multiple voltage shifters to respectively receive multiple selection signals, shifting the peak voltage values ​​of the multiple selection signals to generate multiple processed signals; providing an operation circuit to perform a signal decoding operation according to the multiple processed signals to generate multiple selection signals; and enabling the operation circuit to respectively provide the multiple selection signals to multiple drivers in the driving device so that the multiple drivers respectively generate multiple driving signals.

[0019] In a preferred embodiment, the step of shifting the peak voltage values ​​of the plurality of selection signals to generate the plurality of processed signals includes: adjusting the peak voltage of each corresponding selection signal from a first voltage value to a second voltage value, wherein the first voltage value is smaller than the second voltage value.

[0020] In a preferred embodiment, the step of providing an operation circuit to perform the signal decoding operation according to the multiple processed signals to generate the multiple selection signals includes: performing the signal decoding operation on the multiple processed signals by performing a logic operation and generating the multiple selection signals.

[0021] In a preferred embodiment, the multiple selection signals include a first selection signal and a second selection signal, wherein the step of providing the operation circuit to perform the signal decoding operation according to the multiple processed signals to generate the multiple selection signals further includes: performing an OR operation on the first processed signal and the second processed signal to generate a first selection signal; performing an AND operation on the first processed signal and the second processed signal to generate a first signal; performing an AND operation on the first signal and the second processed signal to generate a second selection signal; and performing an AND operation on the first signal and the first processed signal to generate a third selection signal, wherein the first processed signal corresponds to the first selection signal, and the second processed signal corresponds to the second selection signal.

[0022] Based on the above, the control circuit of the present invention is used to receive the selection signal from the encoder and obtain the selection signal by decoding the selection signal. The control circuit of the present invention provides the selection signal to the driving device, and the driving device can drive one or more light-emitting diodes according to the selection signal. By setting the control circuit of the present invention, the number of light-emitting elements of the projection device can be appropriately expanded, and the working efficiency of the projection device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a projection device showing a control circuit according to an embodiment of the present invention is shown.

[0024] Figure 2 A schematic diagram of a control circuit of a projection device according to an embodiment of the present invention is shown.

[0025] Figure 3 A schematic diagram of a projection device according to an embodiment of the present invention is shown.

[0026] Figure 4 A flow chart of a control method of a driving device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0027] In order to provide a further understanding of the purpose, structure, features, and functions of the present invention, the following detailed description is given in conjunction with the embodiments.

[0028] Please refer to Figure 1 , Figure 1 A schematic diagram of a projection device of a control circuit according to an embodiment of the present invention is shown. The projection device 100 may be a pico projector. The projection device 100 includes a control circuit 110 and a driving device 120. The driving device 120 is used to drive a plurality of light emitting elements LD1-LDM. The light emitting elements LD1-LDM may be light emitting diodes, laser diodes, or any other light emitting elements known to those skilled in the art.

[0029] In the present embodiment, the control circuit 110 is coupled to the driving device 120. The control circuit 110 includes voltage shifters 1111-111N and an operation circuit 112. The voltage shifters 1111-111N can receive the selection signals LED_SEL1-LED_SELN respectively. Here, the selection signals LED_SEL1-LED_SELN can be encoded signals and generated by an encoder outside the control circuit 110. The voltage shifters 1111-111N respectively perform voltage shifting operations on the received selection signals LED_SEL1-LED_SELN to generate a plurality of processed signals PS1-PSN respectively. In detail, the voltage shifters 1111-111N are used to adjust the voltage peaks of the selection signals LED_SEL1-LED_SELN from the first voltage to the second voltage to generate the processed signals PS1-PSN respectively. In the present embodiment, the first voltage can be less than the second voltage.

[0030] In addition, the operation circuit 112 is coupled to the voltage shifters 1111 ˜ 111N. The operation circuit 112 receives the processed signals PS1 ˜PSN respectively provided by the voltage shifters 1111 ˜ 111N, performs signal decoding on the processed signals PS1 ˜PSN, and generates a plurality of selection signals STB1 ˜STBM through the signal decoding.

[0031] On the other hand, the operation circuit 112 is coupled to the driving device 120. The driving device 120 is further coupled to the light-emitting elements LD1-LDM. The driving device 120 receives the selection signals STB1-STBM generated by the operation circuit 112, and the driving device 120 can generate driving signals DV1-DVM respectively according to the selection signals STB1-STBM. The driving device 120 also provides the driving signals DV1-DVM to the light-emitting elements LD1-LDM respectively, and thereby controls whether each of the light-emitting elements LD1-LDM emits light, and can further control the light intensity thereof.

[0032] In this embodiment, the operation circuit 112 can perform signal decoding operations through logical operations. The driving device 120 can generate driving signals DV1-DVM as current signals or voltage signals according to the corresponding selection signals STB1-STBM to drive the light-emitting elements LD1-LDM respectively. In this embodiment, the values ​​of the driving signals DV1-DVM can be set by the designer according to the specifications of the light-emitting elements LD1-LDM without specific restrictions.

[0033] In this embodiment, the number of selection signals LED_SEL1-LED_SELN can determine the number of controllable light emitting elements LD1-LDM. Taking N selection signals LED_SEL1-LED_SELN as an example, the number of controllable light emitting elements LD1-LDM of the projection device 100 can be equal to 2 to the Nth power minus 1 at most.

[0034] It is worth noting that in this embodiment, the control circuit 110 can be used in conjunction with the driving device 120 to decode the selection signals LED_SEL1 to LED_SELN so that the driving device 120 generates driving signals DV1 to DVM to count the light emitting elements LD1 to LDM. In this way, in addition to the light emitting elements originally provided in the projection device 100, a plurality of light emitting elements LD1 to LDM can be additionally expanded to serve as projection light sources. This can effectively improve the display performance of the projection device 100.

[0035] Please refer to the following Figure 2 , Figure 2 A schematic diagram of a control circuit of a projection device according to an embodiment of the present invention is shown. The control circuit 200 includes voltage shifters 211, 212 and a computing circuit 220. The voltage shifters 211, 212 receive selection signals LED_SEL1 and LED_SEL2, respectively. The output ends of the voltage shifters 211, 212 are coupled to the computing circuit 220 and provide processed signals PS1, PS2 to the computing circuit 220, respectively.

[0036] In detail, the voltage shifter 211 includes a transistor Q1 and resistors R1 to R3. The control terminal of the transistor Q1 is coupled to the resistor R1, and receives the selection signal LED_SEL1 through the resistor R1. The first terminal of the transistor Q1 is coupled to the resistor R3, and receives the operating voltage V2 through the resistor R3. In addition, the resistor R2 is coupled between the control terminal and the second terminal of the transistor Q1, and the second terminal of the transistor Q1 is coupled to the reference ground terminal GND. The voltage shifter 212 includes a transistor Q2 and resistors R4 to R6. The control terminal of the transistor Q2 is coupled to the resistor R4, and receives the selection signal LED_SEL2 through the resistor R4. The first terminal of the transistor Q4 is coupled to the resistor R5, and receives the operating voltage V2 through the resistor R5. In addition, the resistor R6 is coupled between the control terminal and the second terminal of the transistor Q2, and the second terminal of the transistor Q2 is coupled to the reference ground terminal GND.

[0037] In terms of operation details, the voltage shifters 211 and 212 can perform similar operation actions. The voltage shifter 211 is used as an example for description. The selection signal LED_SEL1 can be a square wave that switches between the operation voltage V1 and the ground voltage. The operation voltage V1 can be less than the operation voltage V2. When the selection signal LED_SEL1 is the operation voltage V1, the transistor Q1 can be turned on and the generated processed signal PS1 can be pulled down to the ground voltage. Conversely, when the selection signal LED_SEL1 is the ground voltage, the transistor Q1 can be turned off and the generated processed signal PS1 can be pulled up to the operation voltage V2. That is, the peak voltage of the selection signal LED_SEL1 (equal to the operation voltage V1) is equal to the peak voltage of the operation voltage V2 through the voltage shifting action of the voltage shifter 211. In this embodiment, the operation voltage V1 can be, for example, 1.8V, and the operation voltage V2 can be, for example, 3.3V, but it is not limited thereto.

[0038] It is worth mentioning that the voltage shifters 211 and 212 in the embodiment of the present invention are inverting voltage shifters, wherein the logic values ​​of the selection signals LED_SEL1 and LED_SEL2 and the corresponding processed signals PS1 and PS2 are complementary to each other.

[0039] On the other hand, in the present embodiment, the operation circuit 220 includes a NOR gate NO2, a NAND gate ND1, and an AND gate AD1 and AD2. The NOR gate NO2 receives the processed signals PS1 and PS2, and performs a NOR operation on the processed signals PS1 and PS2 to generate a selection signal STBB. The NAND gate ND1 receives the processed signals PS1 and PS2, and performs a NAND operation on the processed signals PS1 and PS2 to generate a signal A1. The AND gate AD1 receives the signal A1 and the processed signal PS2, and performs an AND operation on the signal A1 and the processed signal PS2 to generate a selection signal STBG. The AND gate AD2 receives the signal A1 and the processed signal PS1, and performs an AND operation on the signal A1 and the processed signal PS1 to generate a selection signal STBR.

[0040] The operation circuit 220 can transmit the strobe signals STBB, STBG and STBR to the driving device, and enable the driving device to generate a driving signal to drive the corresponding light-emitting element. In this embodiment, the strobe signal STBB can correspond to the blue light-emitting element; the strobe signal STBG can correspond to the green light-emitting element; and the strobe signal STBR can correspond to the red light-emitting element.

[0041] In this embodiment, the truth table of the selection signals LED_SEL1, LED_SEL2 and the selection signals STBB, STBG and STBR can be shown in the following table:

[0042] LED_SEL1 LED_SEL2 STBB STBG STBR 0 0 0 0 0 0 1 0 0 1 1 0 0 1 0 1 1 1 0 0

[0043] It can be seen from the above truth table that in this embodiment, according to the logic values ​​of the selection signals LED_SEL1 and LED_SEL2, all three light-emitting elements can be turned off, or one of the three light-emitting elements can be turned on. It is worth mentioning that the logic values ​​of the selection signals LED_SEL1 and LED_SEL2 can change dynamically over time. In this way, by selecting the combination of the logic values ​​of the signals LED_SEL1 and LED_SEL2, each light-emitting element can be dynamically turned on or off. By controlling the lighting time of each light-emitting element, the brightness of each light-emitting element can be adjusted.

[0044] Please note that in the embodiment of the present invention, only two selection signals LED_SEL1 and LED_SEL2 are used for illustration, which does not mean that the number of selection signals in the embodiment of the present invention is limited to two. In the scope of the present invention, the number of selection signals received by the control circuit can also be greater than 2 without specific limitation.

[0045] In addition, the circuit details of the voltage shifters 211 and 212 are not limited to Figure 2 The content shown. Any circuit architecture of any voltage shifter known to those skilled in the art can be applied to the present invention without any particular limitation. Similarly, the logic gate architecture in the operation circuit 220 is only an example for illustration and is not intended to limit the scope of implementation of the present invention. Among them, those skilled in the art know that under the same operation function, the combination of logic gates in the logic circuit can have a variety of transformation methods.

[0046] Please refer to Figure 3 , Figure 3 A schematic diagram of a projection device according to an embodiment of the present invention is shown. The projection device 300 includes an encoder 301, a control circuit 310, a driving device 320, and light-emitting elements LD1-LD3. The encoder 301 sends encoded selection signals LED_SEL1 and LED_SEL2. The control circuit 310 is coupled to the encoder 301 and receives the selection signals LED_SEL1 and LED_SEL2. The control circuit 310 decodes the selection signals LED_SEL1 and LED_SEL2 and generates a plurality of strobe signals.

[0047] The driving device 320 includes drivers 321, 322, and 323. The drivers 321, 322, and 323 are coupled to the light emitting elements LD1, LD2, and LD3, respectively. The drivers 321, 322, and 323 are also coupled to the control circuit 310, and receive the selection signals generated by the control circuit 310, respectively. Further, the drivers 321, 322, and 323 generate a plurality of driving signals according to the received selection signals, and drive the light emitting elements LD1, LD2, and LD3, respectively, through the driving signals.

[0048] The implementation details of the control circuit 310 have been described in detail in the aforementioned embodiments and will not be elaborated herein.

[0049] In addition, the drivers 321, 322 and 323 may be current drivers or voltage drivers for generating driving signals of current signals or voltage signals to drive the light emitting elements LD1, LD2 and LD3 respectively. In this embodiment, the drivers 321, 322 and 323 may be implemented by using any driving circuit of a light emitting element known to a person skilled in the art, without any specific limitation. The encoder 301 may be provided in a control chip and implemented by a digital circuit.

[0050] In the present embodiment, the projection device 300 may be a pico projector. The encoder 301 may be further coupled to a digital light processor (DLP) 302. The digital light processor 302 is originally configured to drive light emitting elements. However, the number of light emitting elements required for the projection device 300 needs to be increased, and the digital light processor 302 does not have sufficient driving capability to drive the light emitting elements LD1, LD2, and LD3. Therefore, the projection device 300 of the present invention may perform the driving operation of the light emitting elements LD1, LD2, and LD3 by setting a control circuit 310 and a driving device 320, which may effectively expand the number of light emitting elements in the projection device 300.

[0051] In this embodiment, the light emitting element originally connected to the output end of the digital light source processor 302 can be removed and left in an empty state. In addition, the digital light source processor 302 can also be used to power other components, such as powering precision components such as spatial light modulators, such as DMD, LCD, etc.

[0052] Incidentally, in this embodiment, the number of light emitting elements is increased according to actual needs. Thus, the number of drivers in the driving device 320 can be expanded corresponding to the number of light emitting elements, thereby improving the working performance of the projection device 300.

[0053] Please refer to Figure 4 , Figure 4 A flow chart of a control method of a driving device according to an embodiment of the present invention is shown. In step S410, a plurality of voltage shifters are provided to receive a plurality of selection signals respectively, and the peak voltage values ​​of the selection signals are shifted to generate a plurality of processed signals. In step S420, an operation circuit is provided to perform a signal decoding operation according to the processed signals to generate a plurality of selection signals. Furthermore, in step S430, the operation circuit is made to provide selection signals to a plurality of drivers in the driving device respectively so that the drivers respectively generate a plurality of driving signals.

[0054] The implementation details of the above steps have been described in detail in the aforementioned embodiments and will not be elaborated here.

[0055] In summary, the control circuit of the present invention generates a plurality of strobe signals by decoding the selection signal. The driving device can generate a driving signal to drive the light-emitting element according to the strobe signal. In the embodiment of the present invention, the projection device can increase the number of drivable light-emitting elements and improve the performance of the projection device by using a control circuit with a simple structure and a corresponding driving device.

[0056] The present invention has been described by the above-mentioned relevant embodiments, however, the above-mentioned embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, changes and modifications made without departing from the spirit and scope of the present invention are all within the scope of patent protection of the present invention.

Claims

1. A control circuit, which drives a plurality of light-emitting elements through a driving device, characterized in that: The control circuit includes: A plurality of voltage shifters, respectively receiving a plurality of selection signals, shifting peak voltage values ​​of the plurality of selection signals to generate a plurality of processed signals; and The operation circuit is coupled to the plurality of voltage shifters and performs a signal decoding operation according to the plurality of processed signals to generate a plurality of strobe signals. The operation circuit provides the plurality of strobe signals to the plurality of drivers in the driving device respectively so that the plurality of drivers generate a plurality of driving signals respectively.

2. The control circuit according to claim 1, characterized in that: Each of the voltage shifters adjusts the peak voltage of each of the corresponding selection signals from a first voltage value to a second voltage value, wherein the first voltage value is smaller than the second voltage value.

3. The control circuit according to claim 1, characterized in that: Each of the voltage shifters comprises: A first resistor having a first end receiving an operating voltage; A second resistor having a first end receiving the corresponding selection signal; a transistor, wherein a first terminal of the transistor is coupled to the second terminal of the first resistor, a control terminal of the transistor is coupled to the second terminal of the second resistor, and a second terminal of the transistor is connected to a reference ground terminal; and A third resistor is coupled between the second terminal of the transistor and the control terminal. The first end of the transistor generates the corresponding processed signal.

4. The control circuit according to claim 3, characterized in that: The operating voltage is greater than a peak voltage of the selection signal.

5. The control circuit according to claim 1, characterized in that: The operation circuit performs the signal decoding operation on the plurality of processed signals by performing logic operations and generates the plurality of strobe signals.

6. The control circuit according to claim 1, characterized in that: The plurality of selection signals include a first selection signal and a second selection signal, the operation circuit performs an OR operation on the first processed signal and the second processed signal to generate a first selection signal; the operation circuit performs an AND operation on the first processed signal and the second processed signal to generate a first signal, the operation circuit performs an AND operation on the first signal and the second processed signal to generate a second selection signal; the operation circuit performs an AND operation on the first signal and the first processed signal to generate a third selection signal, wherein the first processed signal corresponds to the first selection signal, and the second processed signal corresponds to the second selection signal; Wherein, the operation circuit comprises: A NOR gate receives the first processed signal and the second processed signal and generates the first selection signal; A NAND gate receives the first processed signal and the second processed signal and generates the first signal; A first AND gate receives the first signal and the second processed signal to generate the second selection signal; and The second AND gate receives the first signal and the first processed signal to generate the third selection signal.

7. A projection device, characterized in that: include: a plurality of light emitting elements; A driving device, generating a plurality of driving signals according to the plurality of strobe signals to drive the plurality of light emitting elements respectively; as well as The control circuit as described in any one of claims 1 to 6 is coupled to the driving device.

8. A control method for a driving device, the driving device being used to drive a plurality of light-emitting elements, characterized in that: The control method includes: Providing a plurality of voltage shifters to respectively receive a plurality of selection signals and shift the peak voltage values ​​of the plurality of selection signals to generate a plurality of processed signals; providing an operation circuit to perform a signal decoding operation according to the plurality of processed signals to generate a plurality of strobe signals; and The operation circuit provides the plurality of strobe signals to the plurality of drivers in the driving device respectively so that the plurality of drivers generate a plurality of driving signals respectively.

9. The control method according to claim 8, characterized in that: The step of shifting the peak voltage values ​​of the plurality of selection signals to generate the plurality of processed signals comprises: The peak voltage of each corresponding selection signal is adjusted from a first voltage value to a second voltage value, wherein the first voltage value is smaller than the second voltage value.

10. The control method according to claim 8, characterized in that: The step of providing an operation circuit to perform the signal decoding operation according to the plurality of processed signals to generate the plurality of strobe signals comprises: performing the signal decoding operation on the plurality of processed signals by performing a logic operation and generating the plurality of strobe signals; The plurality of selection signals include a first selection signal and a second selection signal, and the step of providing the operation circuit to perform the signal decoding operation according to the plurality of processed signals to generate the plurality of selection signals also includes: performing a NOR operation on the first processed signal and the second processed signal to generate a first selection signal; performing a NAND operation on the first processed signal and the second processed signal to generate a first signal; performing an AND operation on the first signal and the second processed signal to generate a second selection signal; and performing an AND operation on the first signal and the first processed signal to generate a third selection signal, The first processed signal corresponds to the first selection signal, and the second processed signal corresponds to the second selection signal.

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