Introduction to the Working Form of Key Switch
Release time：2019-07-18 Clicks： Click
What is the working form of the key switch? What is the specific situation when it works? Let's give you a detailed introduction.
How does the key switch work?
Keyboard switches are well used in many enterprises'production, which can enable people to achieve more aspects of operation, so as to achieve efficient production. So how do keyboard switches work?
In fact, the key switch, we can see as a delay circuit, consisting of a large capacitor, a large resistance, and an insulated gate FET. When triggered, it charges the capacitor, and the trigger cycle ends. At this time, the gate capacitor of the insulated gate acts on a high voltage field in the gate. The effect transistor is turned on, and the drain of the gate is connected with a load, so the load works. Because the resistance of the gate to the ground is very high, usually hundreds of megaohms, so the discharge is slow, so we need to add a discharge resistance, usually adjustable resistance, to adjust the delay time. The resistance is large, the delay is long, the resistance is small and the delay is short. When the capacitor is dead and the gate voltage is dead, the FET enters the cut-off state and the drain load stops working.