DC3-5V Digital Temperature DIY Kit Temperature sensor Sound and Light Alarm

With simple circuits and easy soldering, this suite is perfect for teens learning circuits and soldering. This suite is characterized by its small size and high sensitivity. It uses sound and light to complete the alarm, and it can be used to detect temperature. In short, it has high practicality

1. Circuit introduction

The circuit of this suite is very simple, it consists of three triodes (two S09014 and one S9015), an activity buzzer, an LED and a thermistor. Adjust the potential to set the temperature threshold, and use two S9014 transistors to drive the buzzer. When the temperature is lower than the threshold, the LED light and buzzer alarm high; when the temperature is lower than the threshold, the LED does not emit light and the buzzer does not Call the police.

2. Parameter

Working voltage: DC3-5V

PCB size: 21*30mm