[Self-made small refrigerator] thermostat Design

1. design objectives

(1) Four-way control, up to four semiconductor refrigeration units

(2) Two-way sensor input with two temperature sensor headers.

(3) LCD display, with menus, temperature setting and other parameters.

(4) set the date and enable it regularly.

(5) Smart fan control, which can be started based on real-time temperature.

(6) High Power, 4x100 W

(7) Good heat dissipation.

 

2. Circuit Diagram Drawing

 

It consists of the following parts:

(1) MCU, fig, MCU core

(2) ds1302, at24c02, date, storage module

(3) key input.

(4) Temperature Sensor Processing

(5) LCD Control

(6) filter module for noise processing.

(7) electronic switch control module

(8) fan control module

 

3. PCB design

The design should follow the design goal.

 

Area: 15x10 cm * cm

Type: Single Side + jumper

Special: tin wire processing, increase the current flow excessive.

 

At present, I have made the circuit board and still need more detailed tests. You are welcome to discuss it together.