The combination of relay and led small night light realizes the control of small night light cycle on and off

Catalog

1、 Preface

2、 Physical diagram and principle of relay

3、 Code and LED Wiring of night light

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1、 Preface

Relay （relay） It's an electrical control device , It is when the input quantity changes to meet the specified requirements , An electrical device in an electrical output circuit that causes a predetermined step change in the controlled quantity .

The relay has a control system and a controlled system , It is usually used in automatic control circuits , It plays an automatic adjustment in the circuit 、 safeguard 、 Switching circuit, etc .

2、 Physical diagram and principle of relay

A relay is simply a switch , It's just different from the usual switch at home that it's a code switch , The code can be used to control the relay ,VCC Indicates the positive pole of the power supply 、GND Indicates the negative pole of the power supply 、IN Indicates the signal input pin （ Usually with STM32 Chip io Mouth to mouth ）,COM Represents the public end ,NC（normal close） Indicates normally closed end ,NO(normal open) It means to start often

VCC Connect the positive pole of the power supply ,GND Connect the negative pole of the power supply ,LN Pick up STM32 Output pin on （ The input high-level common terminal is normally closed , The input low-level common terminal is normally open ）
In short, it's

When IN When the foot input is high ,NC And COM Connected to a ; When the input power is low ,NO And COM Connected to a

3、 Code and LED Wiring of night light

   

 

  The wiring is as follows

be based on STM32103C8T6 chip （ Other chips can also be used ）

  Night light GND（ white ） Receive STM32 Of GND

  Night light VCC（ Red ） Connected to the relay NO mouth

Relay COM Oral reception STM32 Of VCC

Relay VCC and GND Corresponding receiving STM32 Of VCC and GND

Relay IN Oral reception STM32 Of PA3 mouth

The core source code attachment is as follows

link ：https://pan.baidu.com/s/131ZeDSV-izc-AVJT-MIJYw 
Extraction code ：1008

  Learn from Jiang Xingji , Beginners STM32 I hope you guys will forgive me for the bad writing

If you have any questions, you can raise them below