Introduction

Many adults, especially parents, complain that kids always open the fridge every time they pass by it. Thus, they want something that keeps them away. Like the regular Door alarms, which are an excellent way to keep your home safe from intruders, this fridge door alarm circuit is a perfect way to keep your refrigerator safe from children. So, together with us, let's make this a fun project. The Project requires fundamental electronic components readily available in the market.

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Hardware Required

Circuit Diagram

Working Explanation

The LDR is used in this fridge door alarm circuit as the primary component and two 555 timer ICs. As we know, the fridge has a light in it, which turns On when we open the refrigerator. Here the LDR plays the role. Since ita a light-dependent resistor, when the fridge is closed, the LDR provides high resistance and maintains the resistor R1 fully charged. The potential divider's output voltage appears across the capacitor greater than 2/3Vcc, making the output LOW.