I / O port multiplexing circuit for LED and electric cooker

Abstract

The utility model relates to the technical field of I / O port multiplexing, and discloses an I / O port multiplexing circuit for an LED and an electric cooker, the circuit comprises a control chip, a first LED indicating lamp, a second LED indicating lamp, a perfusion resistor, a push-pull resistor, a zero potential end and a high potential end VCC. A first I / O port of the control chip is provided with three output modes, the first I / O port is connected with the two LED indicating lamps, and the two indicating lamps are controlled to display three indicating states through the push-pull resistor, the zero potential end, the high potential end VCC and the perfusion resistor. The problem of I / O port resource shortage of the I / O port of the control chip under the condition that a composite LED indicating lamp is used for displaying various indicating states is relieved, the I / O port resource utilization rate of the control chip is improved, and meanwhile the requirement for household appliance miniaturization is met.

Description

Technical Field

[0001] The utility model relates to the technical field of I / O port multiplexing, in particular to an I / O port multiplexing circuit for LEDs and an electric rice cooker. Background Art

[0002] With the development of miniaturization of smart home appliances, the corresponding control circuits are becoming more and more streamlined, and the resources of controllers on the market are limited. When choosing a controller model, there are often situations where the controller resources are insufficient or the controller resources cannot match the required functions. Choosing a controller with more resources is likely to waste resources and increase costs, and it cannot meet the needs of miniaturization of home appliances. Utility Model Content

[0003] The purpose of the utility model is to provide an I / O port multiplexing circuit for LED and an electric rice cooker, so as to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0004] The utility model solves the technical problem by providing an I / O port multiplexing circuit for LED and an electric rice cooker.

[0005] According to an embodiment of the first aspect of the utility model, there is provided an I / O port multiplexing circuit for LEDs, comprising: a control chip, a first LED indicator light, a second LED indicator light, a perfusion resistor, a push-pull resistor, a zero potential terminal and a high potential terminal VCC;

[0006] The control chip is provided with a first I / O port, and the first I / O port is provided with a high impedance mode, a push-pull output mode and a PWM output mode;

[0007] The high potential terminal VCC is connected to the anode of the first LED indicator, the cathode of the first LED indicator is connected to the push-pull resistor, the push-pull resistor and the perfusion resistor are both connected to the first I / O port, the perfusion resistor is connected to the anode of the second LED indicator, and the cathode of the second indicator is connected to the zero potential terminal;

[0008] The zero potential terminal is connected to the ground terminal of the control chip, and the high potential terminal VCC is connected to the power supply terminal of the control chip.

[0009] Furthermore, an I / O port multiplexing circuit for LEDs also includes: a current limiting resistor; one end of the current limiting resistor is connected to the first I / O port, and the other end of the current limiting resistor is respectively connected to the pouring resistor and the push-pull resistor.

[0010] Furthermore, the high potential terminal VCC is used to supply a 5V DC voltage.

[0011] Furthermore, the first LED indicator light is a warm color indicator light.

[0012] Furthermore, the second LED indicator light is a cool color indicator light.

[0013] Furthermore, the resistance value range of the push-pull resistor is 1KΩ to 10KΩ.

[0014] Furthermore, the resistance of the perfusion resistor ranges from 1KΩ to 10KΩ.

[0015] Furthermore, the first I / O port outputs a high level signal or a low level signal in a push-pull output mode.

[0016] Furthermore, the first I / O port outputs a PWM signal in a PWM output mode.

[0017] According to an embodiment of the second aspect of the utility model, there is provided an electric rice cooker, comprising an I / O port multiplexing circuit for LEDs according to the embodiment of the first aspect of the utility model.

[0018] The beneficial effects of the utility model are as follows: the first I / O port of the control chip is provided with three output modes, the first I / O port is connected to two LED indicator lights, and the two indicator lights are controlled to display three indication states through a push-pull resistor, a zero potential end, a high potential end VCC and a perfusion resistor, thereby alleviating the problem of tight I / O port resources of the control chip when the composite LED indicator lights are used to display multiple indication states, improving the utilization rate of the I / O port resources of the control chip and meeting the demand for miniaturization of household appliances. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a partial circuit diagram of an I / O port multiplexing circuit for LEDs provided by an embodiment of the utility model;

[0020] Figure 2 It is a schematic diagram of a framework of an I / O port multiplexing circuit for LED and an electric rice cooker provided by an embodiment of the utility model;

[0021] Figure 3 The utility model is another embodiment of an I / O port multiplexing circuit for LED and a partial circuit diagram of an electric rice cooker. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and cannot be understood as limiting the present utility model.

[0023] It should be noted that although the functional module division is performed in the schematic diagram, in some cases, the module division can be different from that in the system.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0026] With the development of miniaturization of smart home appliances, the corresponding control circuits are becoming more and more streamlined, and the resources of controllers on the market are limited. When choosing a controller model, there are often situations where the controller resources are insufficient or the controller resources cannot match the required functions. Choosing a controller with more resources is likely to waste resources and increase costs, and it cannot meet the needs of miniaturization of home appliances.

[0027] Reference Figure 1 In some embodiments of the first aspect of the utility model, an I / O port multiplexing circuit for LED includes: a control chip U1, a perfusion resistor R2, a push-pull resistor R1, a zero potential end, a high potential end VCC, a first LED indicator light D1 and a second LED indicator light D2.

[0028] The control chip U1 is provided with a first I / O port, and the first I / O port has a high impedance mode, a push-pull output mode and a PWM output mode. The control chip may be an STM32 single-chip microcomputer or a C51 single-chip microcomputer.

[0029] The high potential terminal VCC is electrically connected to the anode of the first LED indicator D1, the cathode of the first LED indicator D1 is electrically connected to one end of the push-pull resistor R1, and the other end of the push-pull resistor R1 is electrically connected to the first I / O port and one end of the perfusion resistor R2, respectively. The push-pull resistor R1 may have a value ranging from 1KΩ to 10KΩ.

[0030] One end of the perfusion resistor R2 is electrically connected to the first I / O port and the other end of the push-pull resistor R1, respectively, the other end of the perfusion resistor R2 is electrically connected to the anode of the second LED indicator D2, and the cathode of the second LED indicator D2 is electrically connected to the zero potential end. The resistance value range of the perfusion resistor R2 can be 1KΩ to 10KΩ.

[0031] The zero potential terminal is electrically connected to the ground terminal of the control chip U1 , and the high potential terminal VCC is electrically connected to the power supply terminal of the control chip U1 .

[0032] The current direction of the perfusion resistor R2 is from the first I / O port through the perfusion resistor R2 to the zero potential end. The current direction of the push-pull resistor R1 is from the high potential end VCC through the push-pull resistor R1 to the first I / O port.

[0033] In one embodiment, when the first I / O port is in high impedance mode, since the voltage drop of the first LED indicator D1 and the second LED indicator D2 is 3V, the first LED indicator D1 and the second LED indicator D2 are connected in series at 6V, and the DC voltage supplied by the high potential terminal VCC cannot drive the first LED indicator D1 and the second LED indicator D2 to light up, and both LED indicators are in an off state. The high potential terminal VCC is used to output a 5V DC voltage.

[0034] In one embodiment, when the first I / O port is in the push-pull output mode, when the first I / O port outputs a high-level signal, due to the high potential end VCC and the zero potential end, the high-level signal passes through the perfusion resistor R2 but not the push-pull resistor R1, the second LED indicator D2 is in the lit state, and the first LED indicator D1 is in the off state, thereby displaying the first indication state of the dual LED indicator.

[0035] In one embodiment, when the first I / O port is in the push-pull output mode, when the first I / O port outputs a low-level signal, due to the high potential end VCC and the zero potential end, the high potential end VCC passes through the push-pull resistor R1 and does not pass through the perfusion resistor R2, the first LED indicator D1 is in a lit state, and the second LED indicator D2 is in an off state, thereby realizing the second indication state of the dual LED indicator lights. It should be noted that the voltage of the low-level signal at this time is lower than the voltage drop of the second LED light.

[0036] In one embodiment, when the first I / O port is in PWM output mode, when the first I / O port outputs a PWM signal, due to the high potential end VCC and the zero potential end, the high voltage segment of the PWM signal passes through the perfusion resistor R2, and the low voltage segment of the PWM signal passes through the push-pull resistor R1, and the first LED indicator D1 and the second LED indicator D2 are both in a lit state, thereby realizing the dual LED indicator to form a third indication state.

[0037] In this embodiment, the number of the first LED indicator lights D1 and the number of the second LEDs can be multiple, multiple first LED indicator lights D1 are connected end to end, or multiple second LED indicator lights D2 are connected end to end, and the DC voltage output by the high potential terminal VCC is supplied accordingly.

[0038] The first I / O port of the control chip U1 is provided with three output modes. The first I / O port is connected to two LED indicator lights. Through the push-pull resistor R1, the zero potential end, the high potential end VCC and the perfusion resistor R2, the two indicator lights are controlled to display three indication states, thereby alleviating the problem of tight I / O port resources of the control chip U1 when the composite LED indicator lights are used to display multiple indication states, improving the utilization rate of the I / O port resources of the control chip U1 and meeting the demand for miniaturization of household appliances.

[0039] Reference Figure 1 In some embodiments of the present invention, the I / O port multiplexing circuit further includes: a current limiting resistor R3. One end of the current limiting resistor R3 is electrically connected to the first I / O port, the other end of the current limiting resistor R3 is electrically connected to one end of the current perfusion resistor R2, and the other end of the current limiting resistor R3 is electrically connected to the other end of the push-pull resistor R1.

[0040] Reference Figure 1 In some embodiments of the present invention, the first LED indicator light D1 is a warm light, and the first LED indicator light D1 can emit warm light, and the second LED indicator light D2 is a cold light, and the second LED indicator light D2 can emit cold light.

[0041] In this embodiment, the lighting effect is combined with the three indication states to indicate the current operating state of the smart home appliance, guide the user to select the correct function, and prompt the user with information, making the indication state effect more prominent.

[0042] In some embodiments of the second aspect of the utility model, an electric rice cooker includes an I / O port multiplexing circuit for LEDs in the first aspect of the utility model.

[0043] Reference Figure 2 and Figure 3 , the rice cooker also includes: a power management circuit and a PWM regulation circuit.

[0044] The input end of the power management circuit is electrically connected to the external power supply end, and the output end of the power management circuit is electrically connected to the high potential end in the I / O port multiplexing circuit. The power management circuit is used to convert the AC voltage input from the external power supply end to obtain the DC voltage required by the I / O port multiplexing circuit, and supply the required DC voltage to the high potential end of the I / O port multiplexing circuit.

[0045] In this embodiment, refer to Figure 3 The power management circuit includes: a transformer T1, a rectifier BD1 and a filtering and voltage stabilizing circuit.

[0046] The output end of the PWM regulation circuit is electrically connected to the control chip in the I / O port multiplexing circuit. The PWM regulation circuit is used to respond to user instructions and output a regulation signal to the control chip in the I / O port multiplexing circuit to adjust the high and low level ratio of the period of the PWM signal output by the first I / O port of the control chip, that is, to adjust the duty cycle of the PWM.

[0047] In this embodiment, the PWM regulation circuit includes: a response button and an adjustment resistor. The response button is connected to the adjustment resistor and the control chip respectively, and the adjustment resistor is connected to the high potential end. The response button responds to the user instruction and outputs the adjustment signal to the control chip to adjust the duty cycle of the PWM signal.

[0048] When the duty cycle of PWM is small, the effect of both LED lights being lit at the same time is achieved through the persistence of vision of the human eye. When the duty cycle of PWM is large, the effect of alternating flashing of the two LEDs is achieved.

[0049] The preferred implementation methods of the utility model are specifically described above, but the invention of the utility model is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the utility model. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An I / O port multiplexing circuit for LED, characterized in that: include: Control chip, first LED indicator light, second LED indicator light, perfusion resistor, push-pull resistor, zero potential terminal and high potential terminal VCC; The control chip is provided with a first I / O port, and the first I / O port is provided with a high impedance mode, a push-pull output mode and a PWM output mode; The high potential terminal VCC is connected to the anode of the first LED indicator, the cathode of the first LED indicator is connected to the push-pull resistor, the push-pull resistor and the perfusion resistor are both connected to the first I / O port, the perfusion resistor is connected to the anode of the second LED indicator, and the cathode of the second indicator is connected to the zero potential terminal; The zero potential terminal is connected to the ground terminal of the control chip, and the high potential terminal VCC is connected to the power supply terminal of the control chip.

2. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: Also includes: A current limiting resistor; one end of the current limiting resistor is connected to the first I / O port, and the other end of the current limiting resistor is respectively connected to the perfusion resistor and the push-pull resistor.

3. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The high potential terminal VCC is used to supply a 5V DC voltage.

4. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The first LED indicator light is a warm color indicator light.

5. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The second LED indicator light is a cold color indicator light.

6. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The resistance value of the push-pull resistor ranges from 1KΩ to 10KΩ.

7. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The resistance value of the perfusion resistor ranges from 1KΩ to 10KΩ.

8. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The first I / O port outputs a high level signal or a low level signal in a push-pull output mode.

9. The I / O port multiplexing circuit for LED according to claim 1, characterized in that: The first I / O port outputs a PWM signal in a PWM output mode.

10. An electric rice cooker, characterized in that: An I / O port multiplexing circuit for LEDs comprising any one of claims 1 to 9.

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