A dual NTC control circuit

Abstract

The utility model provides a kind of double NTC control circuit, comprising: voltage reduction subcircuit, the voltage reduction subcircuit is used to convert 220V alternating current into 5V direct current;Switching control subcircuit, the switching control subcircuit is connected in the output of the voltage reduction subcircuit, and the switching control subcircuit is used to control the switching of 5V direct current;Chip control module, the chip control module is connected in the output of the switching control subcircuit, and the switching control subcircuit is used to power supply to the chip control module;LCD subcircuit and LED subcircuit are respectively connected in the chip control circuit;NTC subcircuit, the quantity of the NTC subcircuit is 2, and the NTC subcircuit is respectively connected in the chip control circuit, and the NTC subcircuit is used to realize the temperature monitoring function of baking tray double position;Buzzer subcircuit, the buzzer subcircuit is connected in the chip control circuit, and the buzzer subcircuit is used to provide alarm buzzer prompt function.

Description

Technical Field

[0001] This utility model relates to the field of electrical circuits, and more specifically, to a dual NTC control circuit. Background Technology

[0002] Waffles are a type of baked flatbread that originated in Belgium and are made using an oven equipped with a special baking pan.

[0003] Existing waffle machines typically consist of an upper shell and a lower shell, with an upper baking tray and a lower baking tray installed on the upper and lower shells, respectively. The cavity formed by the upper and lower baking trays after they are closed is the waffle ingredient receiving chamber. Heating devices are installed on the back of both the upper and lower baking trays. The ingredients are poured into the chamber, the mold is closed, and the upper and lower baking trays are heated to a certain temperature and maintained for a period of time. After the ingredients are heated by the heat transferred from the upper and lower baking trays, the moisture in the ingredients evaporates and turns into a solid, thus forming a waffle.

[0004] The existing waffle maker has the problem that it lacks a single-station heating function, making it difficult to control the cooking amount based on the amount of food consumed. When only one station is used to make one waffle, the other station will be wasting heat by heating without heating. Therefore, improvements are needed, and a corresponding circuit design is required. Utility Model Content

[0005] The purpose of this invention is to provide a dual NTC control circuit.

[0006] The present invention aims to solve the problem that existing waffle machine circuits do not have a single-station heating function.

[0007] Compared with the prior art, the technical solution of this utility model and its beneficial effects are as follows:

[0008] A dual NTC control circuit includes: a step-down sub-circuit for converting 220V AC to 5V DC; a switch control sub-circuit connected to the output of the step-down sub-circuit for controlling the switching of the 5V DC power; a chip control module connected to the output of the switch control sub-circuit for powering the chip control module; an LCD sub-circuit connected to the chip control module for providing LCD liquid crystal display functionality; an LED sub-circuit connected to the chip control module for providing LED lighting functionality; two NTC sub-circuits, each connected to the chip control module for temperature monitoring of a dual-station baking pan; and a buzzer sub-circuit connected to the chip control module for providing an alarm buzzer function.

[0009] As a further improvement, the step-down sub-circuit includes: one end of fuse F1 connected to the live wire, the other end of fuse F1 connected to one end of capacitor CX1, the other end of capacitor CX1 connected to the neutral wire, the AC input terminal of rectifier bridge DB1 connected in parallel to capacitor CX1, the positive terminal of electrolytic capacitor EC1 connected to the positive output terminal of rectifier bridge DB1, the negative terminal of electrolytic capacitor EC1 connected to the negative output terminal of rectifier bridge DB1, one end of inductor L3 connected to the positive terminal of electrolytic capacitor EC1, the other end of inductor L3 connected to the positive terminal of electrolytic capacitor EC5, the negative terminal of electrolytic capacitor EC5 connected to the negative terminal of electrolytic capacitor EC1, the DRAIN terminal of controller U1 connected to the positive terminal of electrolytic capacitor EC5, the positive terminal of diode D2 connected to the negative terminal of electrolytic capacitor EC5, the negative terminal of diode D2 connected to the GND terminal of controller U1, one end of resistor R1 connected to the negative terminal of diode D2, and the other end of resistor R1 connected to the CS terminal of controller U1. One end of resistor R2 is connected to the FB terminal of controller U1 and to one end of resistor R7. The other end of resistor R7 is connected to the negative terminal of diode D2. The other end of resistor R2 is connected to one end of capacitor EC2. The other end of capacitor EC2 is connected to the other end of resistor R7. One end of capacitor EC3 is connected to the VDD terminal of controller U1. The other end of capacitor EC3 is connected to the other end of capacitor EC2. The negative terminal of diode D1 is connected to one end of capacitor EC2. One end of inductor L1 is connected to the other end of capacitor EC3. The other end of inductor L1 is connected to the positive terminal of diode D1. The positive terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D1. The negative terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D2. One end of resistor R8 is connected to the positive terminal of electrolytic capacitor EC4 and to the 5V voltage output terminal. One end of resistor R9 is connected to the negative terminal of electrolytic capacitor EC4. The other end of resistor R8 is connected to the other end of resistor R9 and to the ground terminal.

[0010] As a further improvement, the switch control sub-circuit includes: one end of the load side of relay K1 is connected to the 5V voltage input terminal and to one end of resistor R14; the other end of resistor R14 is connected to the cathode of diode D5; the anode of diode D5 is connected to the other end of the load side of relay K1 and to the collector of transistor Q1; the base of transistor Q1 is connected to one end of resistor R4; the other end of resistor R4 is connected to one end of resistor R5; the other end of resistor R5 is connected to one end of resistor R6 and to transistor Q2. The base of the transistor is connected to the emitter of transistor Q2 and grounded. The emitter of transistor Q1 is connected to the collector of transistor Q2. The positive terminal of electrolytic capacitor C2 is connected to one end of resistor R5 and to the negative terminal of diode D3. The negative terminal of electrolytic capacitor C2 is connected to the other end of resistor R6 and to the positive terminal of diode D4. The negative terminal of diode D4 is connected to the positive terminal of diode D3 and to the negative terminal of electrolytic capacitor C1. The positive terminal of electrolytic capacitor C1 is connected to one end of resistor R3. The other end of resistor R3 is the output terminal.

[0011] As a further improvement, the chip control module includes a chip U2, a capacitor C3, and a capacitor C4. One end of capacitor C3 is connected to the 5V voltage input terminal and to the VDD terminal of chip U2, and the other end of capacitor C3 is grounded. One end of capacitor C4 is connected to the 5V voltage input terminal and to the VDD terminal of chip U2, and the other end of capacitor C4 is grounded. The VSS terminal of chip U2 is grounded.

[0012] As a further improvement, the LCD sub-circuit includes an LCD module, a controller U3, capacitor C7, and capacitor C8. The LCD module is connected to the controller U3. The VLCD terminal of the controller U3 is connected to the VDD terminal of the controller U3. The VDD terminal of the controller U3 is connected to the 5V voltage input terminal. One end of capacitor C7 is connected to the VDD terminal of the controller U3, and the other end of capacitor C7 is connected to the VSS terminal of the controller U3 and grounded. One end of capacitor C8 is connected to the VDD terminal of the controller U3, and the other end of capacitor C8 is connected to the VSS terminal of the controller U3 and grounded.

[0013] As a further improvement, the LED sub-circuit includes: the input terminal of the LED module is connected to the 5V voltage input terminal, the output terminal of the LED module is connected to one end of resistor R16, the other end of resistor R16 is connected to one end of resistor R9, the other end of resistor R9 is connected to the collector of transistor Q4, the base of transistor Q4 is connected to one end of resistor R10, the other end of resistor R10 is connected to the LED terminal of chip U2, and the emitter of transistor Q4 is grounded.

[0014] As a further improvement, the NTC sub-circuit includes: one end of the NTC thermistor J1 is connected to the 5V voltage input terminal, the other end of the NTC thermistor J1 is connected to one end of the resistor R20, the other end of the resistor R20 is grounded, one end of the capacitor C5 is connected to the other end of the NTC thermistor J1 and connected to the AD-NTC terminal of the chip U2, and the other end of the capacitor C5 is grounded.

[0015] As a further improvement, the buzzer sub-circuit includes: the positive terminal of buzzer module BZ1 is connected to one end of resistor R17 and connected to the 5V voltage input terminal; the negative terminal of buzzer module BZ1 is connected to the other end of resistor R17; the collector of transistor Q3 is connected to the negative terminal of buzzer module BZ1; the emitter of transistor Q3 is grounded; the base of transistor Q3 is connected to one end of resistor R11; the other end of resistor R11 is connected to one end of resistor R15; and the other end of resistor R15 is connected to the BZ terminal of chip U2.

[0016] The beneficial effects of this utility model are as follows:

[0017] The present invention provides a dual NTC control circuit that combines a step-down sub-circuit, a switch control sub-circuit, a chip control module, an LCD sub-circuit, an LED sub-circuit, an NTC sub-circuit, and a buzzer sub-circuit. This circuit enables dual-station heating and baking tray temperature monitoring in a waffle maker, and allows for individual control of the heating function at each station, as well as single-station heating and simultaneous dual-station heating. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the step-down circuit provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the switch control sub-circuit provided in an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the chip control module provided in an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the LCD sub-circuit provided in an embodiment of the present invention.

[0022] Figure 5 This is a schematic diagram of the LED sub-circuit provided in an embodiment of this utility model.

[0023] Figure 6 This is a schematic diagram of the NTC sub-circuit provided in an embodiment of the present invention.

[0024] Figure 7 This is a schematic diagram of the buzzer circuit provided in an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely to represent selected embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0026] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] Reference Figures 1 to 7 As shown, a dual NTC control circuit includes: a step-down sub-circuit for converting 220V AC to 5V DC; a switch control sub-circuit connected to the output of the step-down sub-circuit for controlling the 5V DC switch; a chip control module connected to the output of the switch control sub-circuit for powering the chip control module; an LCD sub-circuit connected to the chip control module for providing LCD liquid crystal display functionality; an LED sub-circuit connected to the chip control module for providing LED lighting functionality; two NTC sub-circuits, each connected to the chip control module for temperature monitoring of the dual-station baking pan; and a buzzer sub-circuit connected to the chip control module for providing alarm beeping functionality.

[0028] Reference Figure 1As shown, the step-down sub-circuit includes: one end of fuse F1 connected to the live wire, the other end of fuse F1 connected to one end of capacitor CX1, the other end of capacitor CX1 connected to the neutral wire, the AC input terminal of rectifier bridge DB1 connected in parallel to capacitor CX1, the positive terminal of electrolytic capacitor EC1 connected to the positive output terminal of rectifier bridge DB1, the negative terminal of electrolytic capacitor EC1 connected to the negative output terminal of rectifier bridge DB1, one end of inductor L3 connected to the positive terminal of electrolytic capacitor EC1, the other end of inductor L3 connected to the positive terminal of electrolytic capacitor EC5, the negative terminal of electrolytic capacitor EC5 connected to the negative terminal of electrolytic capacitor EC1, the DRAIN terminal of controller U1 connected to the positive terminal of electrolytic capacitor EC5, the positive terminal of diode D2 connected to the negative terminal of electrolytic capacitor EC5, the negative terminal of diode D2 connected to the GND terminal of controller U1, one end of resistor R1 connected to the negative terminal of diode D2, the other end of resistor R1 connected to the CS terminal of controller U1, and so on. One end of resistor R2 is connected to the FB terminal of controller U1 and to one end of resistor R7. The other end of resistor R7 is connected to the negative terminal of diode D2. The other end of resistor R2 is connected to one end of capacitor EC2. The other end of capacitor EC2 is connected to the other end of resistor R7. One end of capacitor EC3 is connected to the VDD terminal of controller U1. The other end of capacitor EC3 is connected to the other end of capacitor EC2. The negative terminal of diode D1 is connected to one end of capacitor EC2. One end of inductor L1 is connected to the other end of capacitor EC3. The other end of inductor L1 is connected to the positive terminal of diode D1. The positive terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D1. The negative terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D2. One end of resistor R8 is connected to the positive terminal of electrolytic capacitor EC4 and to the 5V voltage output terminal. One end of resistor R9 is connected to the negative terminal of electrolytic capacitor EC4. The other end of resistor R8 is connected to the other end of resistor R9 and to the ground terminal.

[0029] Reference Figure 2As shown, the switch control sub-circuit includes: one end of the load side of relay K1 is connected to the 5V voltage input terminal and to one end of resistor R14; the other end of resistor R14 is connected to the cathode of diode D5; the anode of diode D5 is connected to the other end of the load side of relay K1 and to the collector of transistor Q1; the base of transistor Q1 is connected to one end of resistor R4; the other end of resistor R4 is connected to one end of resistor R5; the other end of resistor R5 is connected to one end of resistor R6 and to the base of transistor Q2. The other end of resistor R6 is connected to the emitter of transistor Q2 and grounded. The emitter of transistor Q1 is connected to the collector of transistor Q2. The positive terminal of electrolytic capacitor C2 is connected to one end of resistor R5 and to the negative terminal of diode D3. The negative terminal of electrolytic capacitor C2 is connected to the other end of resistor R6 and to the positive terminal of diode D4. The negative terminal of diode D4 is connected to the positive terminal of diode D3 and to the negative terminal of electrolytic capacitor C1. The positive terminal of electrolytic capacitor C1 is connected to one end of resistor R3. The other end of resistor R3 is the output terminal.

[0030] Reference Figure 3 As shown, the chip control module includes chip U2, capacitor C3 and capacitor C4. One end of capacitor C3 is connected to the 5V voltage input terminal and the VDD terminal of chip U2, and the other end of capacitor C3 is grounded. One end of capacitor C4 is connected to the 5V voltage input terminal and the VDD terminal of chip U2, and the other end of capacitor C4 is grounded. The VSS terminal of chip U2 is grounded.

[0031] Reference Figure 4 As shown, the LCD sub-circuit includes an LCD module, a controller U3, capacitor C7, and capacitor C8. The LCD module is connected to the controller U3. The VLCD terminal of the controller U3 is connected to the VDD terminal of the controller U3. The VDD terminal of the controller U3 is connected to the 5V voltage input terminal. One end of capacitor C7 is connected to the VDD terminal of the controller U3, and the other end of capacitor C7 is connected to the VSS terminal of the controller U3 and grounded. One end of capacitor C8 is connected to the VDD terminal of the controller U3, and the other end of capacitor C8 is connected to the VSS terminal of the controller U3 and grounded.

[0032] Reference Figure 5 As shown, the LED sub-circuit includes: the input terminal of the LED module is connected to the 5V voltage input terminal; the output terminal of the LED module is connected to one end of resistor R16; the other end of resistor R16 is connected to one end of resistor R9; the other end of resistor R9 is connected to the collector of transistor Q4; the base of transistor Q4 is connected to one end of resistor R10; the other end of resistor R10 is connected to the LED terminal of chip U2; and the emitter of transistor Q4 is grounded.

[0033] Reference Figure 6As shown, the NTC sub-circuit includes: one end of NTC thermistor J1 connected to the 5V voltage input terminal, the other end of NTC thermistor J1 connected to one end of resistor R20, the other end of resistor R20 grounded, one end of capacitor C5 connected to the other end of NTC thermistor J1 and connected to the AD-NTC terminal of chip U2, and the other end of capacitor C5 grounded. The main function of the NTC sub-circuit is to monitor the temperature of the baking pan, equivalent to a temperature sensor. The NTC circuit feeds back the detected signal to chip U2 in real time, and chip U2 makes a judgment to determine the on / off state of the heating element circuit, thereby achieving precise temperature control of the heated product. The purpose of the dual NTC circuit is to prevent asymmetrical addition of food to the product and to more accurately detect the temperature of the heating pan and the food.

[0034] Reference Figure 7 As shown, the buzzer sub-circuit includes: the positive terminal of buzzer module BZ1 is connected to one end of resistor R17 and connected to the 5V voltage input terminal; the negative terminal of buzzer module BZ1 is connected to the other end of resistor R17; the collector of transistor Q3 is connected to the negative terminal of buzzer module BZ1; the emitter of transistor Q3 is grounded; the base of transistor Q3 is connected to one end of resistor R11; the other end of resistor R11 is connected to one end of resistor R15; and the other end of resistor R15 is connected to the BZ terminal of chip U2.

[0035] The above embodiments are only used to explain the technical solution of this utility model and are not intended to limit it. Those skilled in the art should understand that any modifications and equivalent substitutions that do not depart from the spirit and scope of this utility model should fall within the protection scope of the claims of this utility model.

Claims

1. A dual NTC control circuit, characterized in that, include: A step-down circuit, which converts 220V AC power into 5V DC power; A switch control sub-circuit is connected to the output terminal of the step-down sub-circuit, and the switch control sub-circuit is used to control the switch of 5V DC power. A chip control module is connected to the output terminal of the switch control sub-circuit, and the switch control sub-circuit is used to supply power to the chip control module. The LCD sub-circuit is connected to the chip control module and is used to provide LCD liquid crystal display function; The LED sub-circuit is connected to the chip control module and is used to provide LED light display function; The NTC sub-circuit consists of two NTC sub-circuits, each connected to the chip control module. The NTC sub-circuit is used to monitor the temperature of the dual-station baking pan. A buzzer sub-circuit is connected to the chip control module and is used to provide an alarm buzzer prompt function.

2. The dual NTC control circuit according to claim 1, characterized in that, The step-down circuit includes: One end of fuse F1 is connected to the live wire, and the other end of fuse F1 is connected to one end of capacitor CX1. The other end of capacitor CX1 is connected to the neutral wire. The AC input terminal of rectifier bridge DB1 is connected in parallel to capacitor CX1. The positive terminal of electrolytic capacitor EC1 is connected to the positive output terminal of rectifier bridge DB1, and the negative terminal of electrolytic capacitor EC1 is connected to the negative output terminal of rectifier bridge DB1. One end of inductor L3 is connected to the positive terminal of electrolytic capacitor EC1, and the other end of inductor L3 is connected to the positive terminal of electrolytic capacitor EC5. The negative terminal of electrolytic capacitor EC5 is connected to the negative terminal of electrolytic capacitor EC1. The DRAIN terminal of controller U1 is connected to the positive terminal of electrolytic capacitor EC5. The positive terminal of diode D2 is connected to the negative terminal of electrolytic capacitor EC5, and the negative terminal of diode D2 is connected to the GND terminal of controller U1. One end of resistor R1 is connected to the negative terminal of diode D2, and the other end of resistor R1 is connected to the CS terminal of controller U1. One end of resistor R2... The following circuits are connected: FB terminal of controller U1 and one end of resistor R7; the other end of resistor R7 is connected to the negative terminal of diode D2; the other end of resistor R2 is connected to one end of capacitor EC2; the other end of capacitor EC2 is connected to the other end of resistor R7; one end of capacitor EC3 is connected to the VDD terminal of controller U1; the other end of capacitor EC3 is connected to the other end of capacitor EC2; the negative terminal of diode D1 is connected to one end of capacitor EC2; one end of inductor L1 is connected to the other end of capacitor EC3; the other end of inductor L1 is connected to the positive terminal of diode D1; the positive terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D1; the negative terminal of electrolytic capacitor EC4 is connected to the positive terminal of diode D2; one end of resistor R8 is connected to the positive terminal of electrolytic capacitor EC4 and is connected to the 5V voltage output terminal; one end of resistor R9 is connected to the negative terminal of electrolytic capacitor EC4; the other end of resistor R8 is connected to the other end of resistor R9 and is connected to the ground terminal.

3. The dual NTC control circuit according to claim 2, characterized in that, The switch control sub-circuit includes: One end of the load side of relay K1 is connected to the 5V voltage input terminal and to one end of resistor R14. The other end of resistor R14 is connected to the cathode of diode D5. The anode of diode D5 is connected to the other end of the load side of relay K1 and to the collector of transistor Q1. The base of transistor Q1 is connected to one end of resistor R4. The other end of resistor R4 is connected to one end of resistor R5. The other end of resistor R5 is connected to one end of resistor R6 and to the base of transistor Q2. The other end of resistor R6... The emitter of transistor Q2 is connected to ground, the emitter of transistor Q1 is connected to the collector of transistor Q2, the positive terminal of electrolytic capacitor C2 is connected to one end of resistor R5 and to the negative terminal of diode D3, the negative terminal of electrolytic capacitor C2 is connected to the other end of resistor R6 and to the positive terminal of diode D4, the negative terminal of diode D4 is connected to the positive terminal of diode D3 and to the negative terminal of electrolytic capacitor C1, the positive terminal of electrolytic capacitor C1 is connected to one end of resistor R3, and the other end of resistor R3 is the output terminal.

4. The dual NTC control circuit according to claim 3, characterized in that, The chip control module includes chip U2, capacitor C3 and capacitor C4. One end of capacitor C3 is connected to the 5V voltage input terminal and the VDD terminal of chip U2, and the other end of capacitor C3 is grounded. One end of capacitor C4 is connected to the 5V voltage input terminal and the VDD terminal of chip U2, and the other end of capacitor C4 is grounded. The VSS terminal of chip U2 is grounded.

5. A dual NTC control circuit according to claim 4, characterized in that, The LCD sub-circuit includes an LCD module, a controller U3, capacitor C7, and capacitor C8. The LCD module is connected to the controller U3. The VLCD terminal of the controller U3 is connected to the VDD terminal of the controller U3. The VDD terminal of the controller U3 is connected to the 5V voltage input terminal. One end of capacitor C7 is connected to the VDD terminal of the controller U3, and the other end of capacitor C7 is connected to the VSS terminal of the controller U3 and grounded. One end of capacitor C8 is connected to the VDD terminal of the controller U3, and the other end of capacitor C8 is connected to the VSS terminal of the controller U3 and grounded.

6. A dual NTC control circuit according to claim 4, characterized in that, The LED sub-circuit includes: the input terminal of the LED module is connected to the 5V voltage input terminal; the output terminal of the LED module is connected to one end of resistor R16; the other end of resistor R16 is connected to one end of resistor R9; the other end of resistor R9 is connected to the collector of transistor Q4; the base of transistor Q4 is connected to one end of resistor R10; the other end of resistor R10 is connected to the LED terminal of chip U2; and the emitter of transistor Q4 is grounded.

7. A dual NTC control circuit according to claim 4, characterized in that, The NTC sub-circuit includes: one end of NTC thermistor J1 is connected to the 5V voltage input terminal, the other end of NTC thermistor J1 is connected to one end of resistor R20, the other end of resistor R20 is grounded, one end of capacitor C5 is connected to the other end of NTC thermistor J1 and connected to the AD-NTC terminal of chip U2, and the other end of capacitor C5 is grounded.

8. A dual NTC control circuit according to claim 4, characterized in that, The buzzer sub-circuit includes: The positive terminal of buzzer module BZ1 is connected to one end of resistor R17 and to the 5V voltage input terminal. The negative terminal of buzzer module BZ1 is connected to the other end of resistor R17. The collector of transistor Q3 is connected to the negative terminal of buzzer module BZ1. The emitter of transistor Q3 is grounded. The base of transistor Q3 is connected to one end of resistor R11. The other end of resistor R11 is connected to one end of resistor R15. The other end of resistor R15 is connected to the BZ terminal of chip U2.

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