Navigation light control circuit and navigation light control box using the same

Abstract

The application discloses a navigation light control circuit and a navigation light control box adopting the same. The navigation light control circuit outputs different reference voltages to control ends of three linear constant current sources according to selected gears, so that each linear constant current source adjusts its output current according to the input reference voltage, thereby simultaneously adjusting brightness of three signal lamps, and further realizing multi-gear brightness synchronous adjustment of the three signal lamps.

Description

Technical Field

[0001] This invention relates to the field of navigation light control technology, and in particular to a navigation light control circuit. Furthermore, it also relates to a navigation light control box employing the aforementioned navigation light control circuit. Background Technology

[0002] Aircraft navigation lights typically consist of three colors: red, green, and white. When flying or taxiing at night, all three colors must be activated simultaneously to help pilots determine the flight or taxiing directions of other aircraft and prevent collisions. Currently, the brightness of all three navigation lights is fixed, with only two settings: on and off. It is not possible to synchronize the brightness of the three navigation lights according to actual conditions. Summary of the Invention

[0003] This invention provides a navigation light control circuit and a navigation light control box using the same, to solve the technical problem in the prior art that it is impossible to synchronously adjust the brightness of three types of navigation lights.

[0004] According to one aspect of the present invention, a navigation light control circuit is provided, comprising a power supply circuit, a brightness adjustment control circuit, and three linear constant current sources. The brightness adjustment control circuit is connected to the power supply circuit and the three linear constant current sources respectively. The three linear constant current sources are connected to three types of signal lights in a one-to-one correspondence. The power supply circuit is used to convert an external power supply voltage into an internal operating voltage. The brightness adjustment control circuit is used to simultaneously output different reference voltages to the control terminals of the three linear constant current sources according to different brightness levels. Each linear constant current source adjusts its output current according to the magnitude of the input reference voltage, thereby achieving synchronous brightness adjustment of the three types of signal lights.

[0005] Furthermore, the power supply circuit includes a DC / DC converter, a three-terminal regulator, and a reference voltage source connected in series. The DC / DC converter is used to step down the external power supply voltage, the three-terminal regulator is used to output a first power supply voltage, and the reference voltage source is used to output a second power supply voltage.

[0006] Furthermore, the brightness adjustment control circuit includes an encoding circuit, three reference voltage circuits, and three multiplexer voltage distributors. The encoding circuit is connected to the address terminals of the three multiplexer voltage distributors, the three reference voltage circuits are connected one-to-one with the analog input terminals of the three multiplexer voltage distributors, and the three multiplexer voltage distributors are connected one-to-one with three linear constant current sources. The encoding circuit is used to select different brightness adjustment levels and encode the level selection state. The reference voltage circuit is used to provide multiple levels of reference voltage to the multiplexer voltage distributors. The number of reference voltage levels is the same as the number of brightness adjustment levels and corresponds one-to-one. The multiplexer voltage distributor is used to select the reference voltage of the corresponding channel and output it to the linear constant current source according to the input encoding.

[0007] Furthermore, the encoding circuit includes a rotary switch and an encoder. The rotary switch is used to select a brightness adjustment level based on a rotation operation, and the encoder is used to encode the level selection state of the rotary switch.

[0008] Furthermore, the number of reference voltage levels and the number of brightness adjustment levels are five.

[0009] Furthermore, the brightness adjustment control circuit includes a five-level dimming switch, three reference voltage circuits, and four quad-bidirectional analog switches. The five-level dimming switch is used to adjust the brightness to five levels. Each reference voltage circuit provides a reference voltage for each of the five levels. The four quad-bidirectional analog switches include a first quad-bidirectional analog switch, a second quad-bidirectional analog switch, a third quad-bidirectional analog switch, and a fourth quad-bidirectional analog switch. The three reference voltage circuits are connected one-to-one with the first, second, and third quad-bidirectional analog switches, respectively. The first four output terminals of each reference voltage circuit are connected to the analog input terminal of the same quad-bidirectional analog switch. The fifth output terminal of each of the three reference voltage circuits... The five-level dimming switch is connected to the analog input terminal of the fourth bidirectional analog switch. Each of the first four output terminals of the five-level dimming switch is simultaneously connected to the control terminals of the first, second, and third bidirectional analog switches. The fifth output terminal of the five-level dimming switch is connected to the control terminal of the fourth bidirectional analog switch. The four output terminals of the first and fourth bidirectional analog switches and the first output terminal of the fourth bidirectional analog switch are connected to the first constant current source. The four output terminals of the second and fourth bidirectional analog switches and the second output terminal of the fourth bidirectional analog switch are connected to the second constant current source. The four output terminals of the third and fourth bidirectional analog switches and the third output terminal of the fourth bidirectional analog switch are connected to the third constant current source. When the brightness level is selected by the five-level dimming switch, the corresponding channels of the first four bidirectional analog switches, the second four bidirectional analog switches, and the third four bidirectional analog switches are simultaneously turned on, or the fourth four bidirectional analog switch is turned on to turn on all channels, so as to output the same reference voltage to the three linear constant current sources at the same time.

[0010] Furthermore, the reference voltage circuit includes five voltage divider circuits connected in parallel, each voltage divider circuit including two voltage divider resistors connected in series, and the midpoint of the two voltage divider resistors serves as the output terminal of that voltage divider circuit.

[0011] Furthermore, it also includes an infrared mode circuit for providing a fixed power supply for the three types of signal lights. The output of the DC / DC converter is connected to the infrared mode circuit and the three-terminal regulator respectively through a mode selection switch. When the mode selection switch is switched to be connected to the three-terminal regulator, it switches to the brightness adjustment mode. When the mode selection switch is switched to be connected to the infrared mode circuit, it switches to the normal mode.

[0012] Furthermore, the model number of the four bidirectional analog switches is CC4066.

[0013] In addition, the present invention also provides a navigation light control box, which employs the navigation light control circuit described above.

[0014] The present invention has the following effects: The navigation light control circuit of the present invention outputs reference voltages of different magnitudes to the control terminals of three linear constant current sources according to the selected level through a brightness adjustment control circuit. This allows each linear constant current source to adjust its own output current according to the input reference voltage, thereby simultaneously adjusting the brightness of the three signal lights and achieving multi-level brightness synchronous adjustment of the three signal lights.

[0015] In addition, the navigation light control box of the present invention also has the above-mentioned advantages.

[0016] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the module structure of the navigation light control circuit according to a preferred embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the encoding circuit in a preferred embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the circuit principle of a reference voltage circuit connected to a five-to-one voltage divider in a preferred embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the brightness adjustment control circuit in another embodiment of the present invention. Detailed Implementation

[0021] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0022] Understandable, such as Figure 1 As shown, a preferred embodiment of the present invention provides a navigation light control circuit, including a power supply circuit, a brightness adjustment control circuit, and three linear constant current sources. The brightness adjustment control circuit is connected to the power supply circuit and the three linear constant current sources respectively. The three linear constant current sources are connected to three types of signal lights one by one. The power supply circuit is used to convert the external power supply voltage into an internal working voltage. The brightness adjustment control circuit is used to select different reference voltages to simultaneously output to the control terminals of the three linear constant current sources according to different settings. Each linear constant current source adjusts the output current according to the input reference voltage, thereby realizing synchronous brightness adjustment of the three types of signal lights.

[0023] It can be understood that the navigation light control circuit in this embodiment outputs different magnitude reference voltages to the control terminals of three linear constant current sources according to the selected level through the brightness adjustment control circuit. This allows each linear constant current source to adjust its own output current according to the input reference voltage, thereby simultaneously adjusting the brightness of the three signal lights and achieving multi-level brightness synchronous adjustment of the three signal lights.

[0024] The power supply circuit includes a DC / DC converter, a three-terminal regulator, and a reference voltage source connected in series. The DC / DC converter steps down the external power supply voltage, the three-terminal regulator outputs a first power supply voltage, and the reference voltage source outputs a second power supply voltage. In essence, the power supply circuit first steps down the external power supply voltage using the DC / DC converter, then uses the three-terminal regulator to convert the voltage into a stable +12V output voltage, and finally uses the reference voltage source to convert the 12V power supply voltage into a +2.5V output voltage to meet the different operating voltage requirements of the internal circuitry.

[0025] It is understood that the brightness adjustment control circuit includes an encoding circuit, three reference voltage circuits, and three multi-select voltage distributors. The encoding circuit is connected to the address terminals of the three multi-select voltage distributors, the three reference voltage circuits are connected one-to-one with the analog input terminals of the three multi-select voltage distributors, and the three multi-select voltage distributors are connected one-to-one with three linear constant current sources. The encoding circuit is used to select different brightness adjustment levels and encode the level selection state. The reference voltage circuit is used to provide multiple levels of reference voltage to the multi-select voltage distributors. The number of reference voltage levels is the same as the number of brightness adjustment levels and corresponds one-to-one. The multi-select voltage distributor is used to select the reference voltage of the corresponding channel and output it to the linear constant current source according to the input encoding. The encoding circuit includes a rotary switch and an encoder. The rotary switch is used to select the brightness adjustment level based on rotation, and the encoder is used to encode the level selection state of the rotary switch. Of course, in other embodiments of the present invention, the encoding circuit can also be a digital encoder. The reference voltage and brightness adjustment have five levels, meaning the rotary switch has five levels and each reference voltage circuit can output five levels of reference voltage. The multi-select voltage distributor is a five-to-one voltage distributor. Of course, in other embodiments of the present invention, the specific number of levels can be selected according to actual needs, such as two, four, six, or eight.

[0026] It is understood that, in the preferred embodiments of the present invention, such as Figure 2 and Figure 3 As shown, the rotary switch has five positions. Each position's output is divided by a resistor. The five outputs of the rotary switch are connected to the encoder's inputs D0-D4, while the encoder's inputs D5-D7 are grounded. When a position is selected by rotation, the encoder encodes the selected position based on the input signal and outputs it as an address to the 5-to-1 voltage divider. The encoder's encoding truth table is shown in Table 1.

[0027] Table 1. Encoding Truth Table

[0028] Three reference voltage circuits provide reference voltages to three linear constant current sources. Each reference voltage circuit provides five reference voltage levels, corresponding to the five brightness adjustment levels of the rotary switch. Each reference voltage circuit operates on a +2.5V voltage provided by the reference voltage source. Each reference voltage circuit includes a parallel five-way voltage divider circuit. Each voltage divider circuit includes two series-connected voltage-dividing resistors, with the midpoint of the two resistors serving as the output terminal. The five reference voltages generated after voltage division are respectively sent to the five analog input terminals of a 5-to-1 voltage divider. The three 5-to-1 voltage dividers share an address bit and are all connected to the encoder output terminal. When the encoder output address bit changes, it can control the corresponding channel of the three 5-to-1 voltage dividers to connect, thereby outputting the same reference voltage to the three linear constant current sources to synchronously adjust the brightness of the three indicator lights. The encoder model is CD4532BM, and the 5-to-1 voltage divider model is CD4097BM.

[0029] It is understood that the brightness adjustment control circuit of the present invention uses a rotary switch and an encoder to form an encoding circuit. The encoder encodes the selected state of the rotary switch. When different brightness adjustment levels are selected, the encoding output by the encoder also changes accordingly. Furthermore, a five-to-one voltage divider is used to form a decoding circuit. The five reference voltage levels are synchronously selected by three five-to-one voltage dividers sharing the address bit, thereby realizing the synchronous adjustment of the brightness levels of the three indicator lights.

[0030] Optionally, such as Figure 4As shown, in another embodiment of the present invention, the brightness adjustment control circuit includes a five-level dimming switch, three reference voltage circuits and four quad bidirectional analog switches. The five-level dimming switch is used to adjust five brightness levels, and each reference voltage circuit is used to provide a reference voltage for the five levels. The four bidirectional analog switches include a first bidirectional analog switch, a second bidirectional analog switch, a third bidirectional analog switch, and a fourth bidirectional analog switch. Three reference voltage circuits are connected one-to-one with the first, second, and third bidirectional analog switches, respectively. The first four outputs of each reference voltage circuit are connected to the analog input of the same bidirectional analog switch. The fifth output of each of the three reference voltage circuits is connected to the analog input of the fourth bidirectional analog switch. Each of the first four outputs of the five-level dimming switch is simultaneously connected to the control terminals of the first, second, and third bidirectional analog switches. The fifth output of the five-level dimming switch is connected to the control terminal of the fourth bidirectional analog switch. The four outputs of the first and fourth bidirectional analog switches are connected to a first constant current source. The four outputs of the second and fourth bidirectional analog switches are connected to a second constant current source. The four outputs of the third and fourth bidirectional analog switches are connected to a third constant current source. When the brightness level is selected by the five-level dimming switch, the corresponding channels of the first, second, and third quadrilateral analog switches are simultaneously activated, or the fourth quadrilateral analog switch is activated to activate all channels, so as to simultaneously output the same reference voltage to the three linear constant current sources. The preferred model of the quadrilateral analog switch is CC4066.

[0031] It is understood that each reference voltage circuit can provide five levels of reference voltage, and three reference voltage circuits correspond to three types of indicator lights, requiring fifteen bidirectional switches for control. However, each quad bidirectional analog switch only has four bidirectional switches, therefore, four quad bidirectional analog switches are needed, one of which needs to be shared. Therefore, this invention connects the first four level outputs of each reference voltage circuit to the four analog inputs of a quad bidirectional analog switch, corresponding to controlling the four brightness levels of one indicator light. The fifth level output of each of the three reference voltage circuits is connected to the three analog inputs of the shared quad bidirectional analog switch, while the other analog input of the shared quad bidirectional analog switch is left floating. When the five-level dimming switch is operated to any of the first four levels, the corresponding channels of the three non-shared quad bidirectional analog switches are connected, thereby controlling the three indicator lights to achieve synchronous brightness adjustment at the first four levels. When the five-level dimming switch is operated to the fifth level, all three channels of the shared quad bidirectional analog switch are connected, thereby controlling the three indicator lights to achieve synchronous brightness adjustment at the fifth level. The brightness adjustment control circuit in this embodiment uses a five-level dimming switch to select and control four bidirectional analog switches. Compared with the brightness adjustment control circuit in the preferred embodiment above, the encoding and decoding process is eliminated, making signal transmission simpler and more reliable.

[0032] In this embodiment, the reference voltage circuit is the same as that in the preferred embodiment described above. That is, the reference voltage circuit includes five parallel voltage divider circuits, each of which includes two voltage divider resistors connected in series. The midpoint of the two voltage divider resistors serves as the output terminal of that voltage divider circuit.

[0033] Optionally, the navigation light control circuit also includes an infrared mode circuit for providing a fixed power supply to the three signal lights. The output of the DC / DC converter is connected to the infrared mode circuit and a three-terminal voltage regulator via a mode selection switch. When the mode selection switch is connected to the three-terminal voltage regulator, the system switches to brightness adjustment mode; when the mode selection switch is connected to the infrared mode circuit, the system switches to normal mode. The infrared mode circuit outputs a stable +28V power supply voltage to the three indicator lights. Furthermore, when the mode selection switch is left floating (not connected to the infrared mode circuit or the three-terminal voltage regulator), the three signal lights are off.

[0034] In addition, another embodiment of the present invention provides a navigation light control box, preferably employing the navigation light control circuit described above.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0036] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A navigation light control circuit, characterized in that, It includes a power supply circuit, a brightness adjustment control circuit, and three linear constant current sources. The brightness adjustment control circuit is connected to the power supply circuit and the three linear constant current sources respectively. The three linear constant current sources are connected to three types of signal lights one by one. The power supply circuit is used to convert the external power supply voltage into the internal working voltage. The brightness adjustment control circuit is used to select different reference voltages to simultaneously output to the control terminals of the three linear constant current sources according to different levels. Each linear constant current source adjusts the output current according to the input reference voltage to achieve synchronous brightness adjustment of the three types of signal lights. The brightness adjustment control circuit includes a five-level dimming switch, three reference voltage circuits, and four quad bidirectional analog switches. The five-level dimming switch is used to adjust the brightness to five levels. Each reference voltage circuit provides a reference voltage for each of the five levels. The four quad bidirectional analog switches are a first quad bidirectional analog switch, a second quad bidirectional analog switch, a third quad bidirectional analog switch, and a fourth quad bidirectional analog switch. The three reference voltage circuits are connected one-to-one with the first, second, and third quad bidirectional analog switches, respectively. The first four level outputs of each reference voltage circuit are connected to the analog input of the same quad bidirectional analog switch. The fifth level output of each of the three reference voltage circuits is connected to the fourth quad bidirectional analog switch. The analog input terminal of the four bidirectional analog switches is connected. Each of the first four output terminals of the five-level dimming switch is simultaneously connected to the control terminals of the first, second, and third bidirectional analog switches. The fifth output terminal of the five-level dimming switch is connected to the control terminal of the fourth bidirectional analog switch. The four output terminals of the first and fourth bidirectional analog switches and the first output terminal of the fourth bidirectional analog switch are connected to the first constant current source. The four output terminals of the second and fourth bidirectional analog switches and the second output terminal of the fourth bidirectional analog switch are connected to the second constant current source. The four output terminals of the third and fourth bidirectional analog switches and the third output terminal of the fourth bidirectional analog switch are connected to the third constant current source. When the brightness level is selected by the five-level dimming switch, the corresponding channels of the first four bidirectional analog switches, the second four bidirectional analog switches, and the third four bidirectional analog switches are simultaneously turned on, or the fourth four bidirectional analog switch is turned on to turn on all channels, so as to output the same reference voltage to the three linear constant current sources at the same time.

2. The navigation light control circuit as described in claim 1, characterized in that, The power supply circuit includes a DC / DC converter, a three-terminal regulator, and a reference voltage source connected in series. The DC / DC converter is used to step down the external power supply voltage, the three-terminal regulator is used to output a first power supply voltage, and the reference voltage source is used to output a second power supply voltage.

3. The navigation light control circuit as described in claim 1, characterized in that, The reference voltage circuit includes five voltage divider circuits connected in parallel. Each voltage divider circuit includes two voltage divider resistors connected in series, and the midpoint of the two voltage divider resistors serves as the output terminal of that voltage divider circuit.

4. The navigation light control circuit as described in claim 2, characterized in that, It also includes an infrared mode circuit for providing a fixed power supply for three types of signal lights. The output of the DC / DC converter is connected to the infrared mode circuit and the three-terminal regulator respectively through a mode selection switch. When the mode selection switch is switched to be connected to the three-terminal regulator, it switches to the brightness adjustment mode. When the mode selection switch is switched to be connected to the infrared mode circuit, it switches to the normal mode.

5. The navigation light control circuit as described in claim 1, characterized in that, The model number of the four bidirectional analog switches is CC4066.

6. A navigation light control box, characterized in that, The navigation light control circuit described in any one of claims 1 to 5 is adopted.

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