# Fifth Lichuang Electronic Design Competition # Temperature alarm system

Note: * is required.

[Please fill in during the registration stage↓]
* 1. Self/team introduction:
Three new electronic designers from the School of Electronics and Information Engineering, Sun Yat-sen University, all share a love for electronic design and the idea of ​​learning from others.
* 2. Briefly introduce the project:
Our team designs a temperature alarm system. It can display the current indoor temperature in real time, and also display the maximum and minimum temperature thresholds; the temperature thresholds are set by the user through buttons. When the temperature is higher than the maximum threshold, the temperature alarm system will issue a high temperature alarm. At this time, a buzzer will sound, an LED light will light up, and a fan will rotate. When the temperature is lower than the minimum threshold, an LED light will light up. up and the other stepper motor will turn.

[Please fill in during the competition stage↓]
* 1. Describe the project details:
This circuit is a temperature measurement, display and alarm system, with the stm32F103C8T6 microcontroller as the main control core. You can use JWAG to download the program, or you can use ISP to download it with one click.

* Use temperature sensor DS18B20 to detect the temperature of the surrounding environment, and then display it in real time through LCD1602, and also display the set maximum temperature threshold and minimum temperature threshold.
* This circuit has four key switches, the first is a confirmation key, the second is a key to reduce the maximum or minimum temperature threshold, the third is to increase the maximum or minimum temperature threshold, and the fourth is a setting key: used Select whether the maximum temperature threshold or the minimum temperature threshold is to be reduced or increased, and you can also select the accuracy of the temperature threshold change.
* This circuit also has two blue LEDs, one lights up when the ambient temperature is above the maximum threshold, and the other lights up when the temperature is below the minimum threshold.
* The buzzer module will sound when the temperature is higher than the maximum threshold, which is to achieve the purpose of alarming and reminding the user.
* < span class="size">The last is the stepper motor and fan module driven by ULN2003AN. When the temperature is higher than the highest threshold, the fan rotates, which is also in line with people's daily thinking; when the temperature is lower than the lowest threshold, another stepper motor rotates. < span class="size">< /span>

* 2. Describe the challenges faced by the project and the problems solved.
Our temperature measurement alarm uses the stm32 minimum system board. The challenges faced by this project mainly lie in the chip and external settings connection. Our peripherals mainly include LCD displays, temperature sensors, fans, and active buzzers. The drive of the fan requires a relatively strong current, so a relay needs to be used to connect the fan and the chip. The chip can drive the fan to rotate when the temperature exceeds the set maximum temperature to achieve the purpose of reducing the temperature. However, due to equipment limitations, the accuracy of the temperature alarm is 0.1, which is difficult to meet the temperature measurement and alarm needs of places with strict temperature requirements. < span class="size">Our temperature alarm can be freely set by the user. When the temperature is lower than the minimum temperature, the chip can be accelerated by itself. When the temperature is higher than the maximum temperature, The fan can be driven to lower the chip display temperature and sound a sharp alarm. Our purpose is to make the chip work in a relatively suitable temperature environment, ensure the normal operation of the equipment, and improve the performance and safety of the equipment. Considering that the components we use are relatively cheap, our temperature alarms can be used in industrial situations, and our temperature alarms can be used inside equipment to ensure that the inside of the equipment works at a relatively suitable temperature. < span class="size">In addition, our devices can also be used in home life. The temperature measurement range of our temperature alarm is 0~99℃ with an accuracy of 0.1, which is enough to meet the needs of daily life. Temperature alarms can first be used as the most common thermometer to display the temperature of the current environment; secondly, temperature alarms can also be used in kitchens, bedrooms, living rooms, etc. to alarm when the temperature exceeds the normal range to prevent possible fires. < span class="size">< /span>
* 3. Describe the key points involved in the hardware and software parts of the project:

* The hardware selected stm32F103C8T6 as the main control chip. It is not expensive but has excellent performance, high operating efficiency and memory. The fast data retrieval speed, coupled with the extremely large number of GPIO pins of the stm32 microcontroller, makes circuit connection easy, and there will be no shortage of pins to connect peripherals.
* In terms of software, keil5 MDK is used as the compiler to encapsulate the underlying functions of stm32F103, making software development simpler and more convenient. At the same time, there are a large number of rich libraries available for calling. Basically every peripheral can call the content of the standard firmware library, so that developers do not need to pay too much attention to the underlying implementation and focus on the overall logical function of the program. < span class="size">< /span>

* 4. Project material list display

| | | | | | | | | | | | |
--- | --- | --- | --- | -- - | --- | --- | --- | --- | --- | --- |
| ID | Name | Designator | Footprint | Quantity | Manufacturer Part | Manufacturer | Supplier | Supplier Part | LCSC Assembly | value(Ω) |
| 1 | 22pF | C18,C17 | C0603 | 2 | CL10C220JB8NNNC | SAMSUNG | LCSC | C1653 | Yes |
| LCSC | C365184 | | |
| 3 | HD44780LCD-1602 | LCD1602 | LCD1602 | 1 |
| 1 | IDC Box 2.54mm 16P Straight | BOOMELE | LCSC | C3406 | | |
| 5 | 1K | R9,R7,R8 | R0603 | 3 | AC0603DR-071KL | YAGEO | LCSC | C227458 |
| ,C5 | C0603 | 2 | 0603N220J500 | WTC | LCSC | C107451 | | |
| 7 | K2-3.6×6.1_SMD | KEY4,KEY2,KEY1,KEY3 | KEY-SMD_2P-L6.2-W3.6-LS8.0 | 4 | K2-1107ST-A4SW-06 | | LCSC | C118141 | | |
| 8 | 1N4148 | D1 | DO-35_BD2.0-L4.2-P8.20-D0.5-RD | 1 | 1N4148 | LGE | LCSC | C402212 | | |
| 9 | 8MHz | X1 | HC-49S_L11. 4-W4.8 | 1 | 49MD-8.00-20-10-10/A | Suzhou Liming Elec | LCSC | C240996 | | |
10 | 104 | C21,C8,C7,C4,C16,C9,C22,C10 | C0603 | 8 | CL10B104KO8NNNC | SAMSUNG | LCSC | C66501 | | |
| 11 | 10uF | C11,C3 | C0603 | 2 | JMK107ABJ106KA-T | Taiyo Yuden | LCSC
| BUZ-TH_BD17.0-P10.00-D0.9|1|HNR-1707|HNDZ|LCSC|C129400||||
13|SYS|PWR1|LED0805-R-RD|1|ORH-R35A|Orient|LCSC | C205444 | Yes | |
| 14 | Red | LED4 | LED0805-R-RD | 1 | ORH-R35A | Orient | LCSC | C205444 | Yes |
| | | | | | |
| 16 | Yellow Green | LED3 | LED0805-R-RD | 1 | ORH-YG35A | Orient | LCSC | C205449 | |
| | C22935 | Yes | |
| 18 | Header2x3 | J3 | HDR-TH_6P-P2.54-V-R2-C3-S2.54 | 1 | Header-Male-2.54_2x3 | BOOMELE | LCSC
| | 12MHZ | Y3 | HC-49US_L11.5-W4.5-P4.88 | 1 | ESA12.0000F20M25F | ZHUHAI MONEC ELEC | LCSC
| 0-P0.50-LS9.0-BL | 1 | STM32F103C8T6 | STMicroelectronics | LCSC | C8734 | Yes | |
| 21 | 2N3904(TO-92) | Q1 | TO-92-3_L5.1-W4.1-P1 .27-L | 1 | 2N3904 | SEMTECH | LCSC | C118538 | | |
| 22 | DS18B20 | U2 | TO-92-3_L4.9-W3.7-P1.27-L | 1 | DS18B20 | , Ltd. | LCSC | C376006 | | |
| 23 | CH340G | U5 | SOIC-16_L9.9-W3.9-P1.27-LS6.0-BR | 1 |
| 24 | ULN2003AN | U1 | DIP-16_16P-L20.2-W6.6-P2.54-LS7.6-BL | 1 | ULN2003AN | TI | LCSC | C90448 | |
| IN1 | MICRO-USB-SMD\_5P\_C40957 | 1 | | ValuePro | LCSC | C40957 | | |
| 26 | Header-Male-2.54_1x20 | J2,J4 | mm 1*20PHeader | BOOMELE | LCSC | C50981 | | |
| 27 | 0 | R5,R10 | R0603 | 2 | RK73Z1JTTD | KOA | LCSC | C130238 | |
| -TH\_BD3.0\_BLUE | 2 | 204-10SUBC/S400-A4 | EVERLIGHT (Taiwan Everlight) | LCSC | C86881 | | | |
29 | TSA363G25-250B | KEY5,KEY6,KEY-UP1,RESET1 | SW -SMD_L6.5-W3.6-LS8.0 | 4 | TSA363G25-250B | BRIGHT | LCSC | C354943 |
| C25804 | Yes | |
31 | 15pF | C19,C20 | C0603 | 2 | C1608C0G2A150JT000N | TDK | LCSC | C342548 | | |
| 32 | Header-Male-2.54_1x8 | H2 | 1 | 210S-1*8P L=11.6MMGold-plated black | Ckmtw | LCSC | C124381 | | |
| 33 | Blue | LED5 | LED0805-R-RD | 1 | ORH-B35A | Orient | LCSC | C205441 | | |
| 34 | 104 | C12,C13 | C0603 | 2 | 0603B104K250 | WTC | LCSC | C83054 | Yes | |
| 35 | HDR-IDC-2.54-2X10P | P1 | -S2.54 | 1 | IDC Box 2.54mm 2X10P Straight | BOOMELE | LCSC | C3405 | | | | 36 | NRF2401 | H3 | HDR-F-2.54_2X4 | 1 | | | LCSC | C239344 |
| | KHz
|
-W1.3-P1.90-LS2.4-BR | 2 | S8050 | High Diode | LCSC | C466625 | | |
| 39 | R\_3386P\_US | RP1 | WH06-2 | 1 | | | LCSC | | | 10K |
| 40 | CAT24C04WI-GT3 | U3 | SOIC-8_L5.0-W4.0-P1.27-LS6.0-BL | 1 | CAT24C04WI-GT3 | ON | LCSC | C71194 | Yes | | |
41 | AMS1117-ADJ | U4 | SOT-223_L6.7-W3.5-P2.30-BR | 1 | AMS1117-ADJ | AMS | LCSC | C6188 | Yes |
| 0-P1.50-D0.8-FD | 2 | electrolytic capacitor10UF50V | ValuePro | LCSC | C32856 | | |
| 43 | 4.7k | R1 | R_AXIAL-0.4 | 1 | | | | | | |
| 44 | 240 | R4,R3 | R_AXIAL-0.4 | 2 | | | | | | |
| 45 | 120 | R2 | R_AXIAL-0.4 | 1 |
| -2.54_1X4 | 1 | | | LCSC | C124378 | | |
| 47 | A2541HWV-4P | H1 | HDR-TH\_4P-P2.54-V\_A2541HWV-4P | 1 |

C225501 |
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​And recorded into video upload
          6.1, video upload competition official website
          6.2, B station video title and link
B station video title: The 5th Lichuang Electronic Design Competition: (Temperature alarm) Self-introduction - Project introduction - Function demonstration - Other
B stations Video link: [https://www.bilibili.com/video/BV125411b75w](https://www.bilibili.com/video/BV125411b75w)< br>
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Notes: ①: Video requirements: Please screen horizontally Shoot, the resolution is no less than 1280×720, the format is Mp4/Mov, the size of a single video is limited to 100M; ②: Video upload: please upload to the official website of the competition and B station simultaneously ([[www.bilibili.com](www.bilibili .com)), the top 10 most popular projects at Station B will receive cash rewards of 1,000-5,000 yuan, and other uploaded projects will receive 100 yuan Lichuang Mall no-threshold coupons; ③: Video title: The 5th Lichuang Electronic Design Competition: {Project Name} - {Video module name}; such as the 5th Lichuang Electronic Design Competition: "Autonomous Driving" project - team introduction. ](http://www.bilibili.com](www.bilibili.com)), the top 10 most popular projects at Station B will receive a cash reward of 1,000-5,000 yuan, and other uploaded projects will receive a 100-yuan Lichuang Mall no-threshold coupon; ③: Video title: The 5th Lichuang Electronic Design Competition: {Project Name}-{Video Module Name}; For example, the 5th Lichuang Electronic Design Competition: "Autonomous Driving" Project - Team Introduction. )< br>

* 6. Open source documents

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