Operating principle of touch switch
There are many kinds of touch switches, and the common ones are as follows:
1. Mechanical touch switch: it is still the traditional button switch, but after improvement, the stroke is short and the pressing interval is small.
2. Double piece conductive switch: the front end is two electrode pieces, and inside is an expanding circuit, which expands the current formed in the two electrode pieces when the finger touches, and drives the later stage circuit to complete the switch or control function.
3. Single chip trigger switch: there is only one electrode at the front end. After touching, the human body receives the electromagnetic wave absorbed from space as an antenna and sends it to the circuit through the electrode. The circuit is a high gain expansion circuit, which can expand a small signal, and use this signal to trigger the subsequent circuit to complete the switching or control function. Due to the need of high input impedance to enlarge the small signal, this kind of circuit has weak static electricity ability and is easy to be damaged by static electricity.
4. Resistance film or conductive film pressure sensitive switch: this kind of switch is completed by a three-layer structure. There is a support lattice between the upper layer and the base layer conductive sheet. Computer keyboard is generally this kind of structure. In fact, it is still the same type as the touch switch, but people can hardly feel the journey.
5. Capacitive touch switch: the capacitor composed of specially shaped PCB (printed circuit board) is used as the trigger condition for touch. Generally, the rigid FR-4 substrate is used. The capacitive touch plate made of this material has a small capacitance base, obvious capacitance change after touch and good function. A slope circuit or frequency voltage conversion circuit is used to judge the change of capacitance and determine whether there is finger touch. This is a better one, which is adopted on the iPod. But it also has the risk of electrostatic breakdown due to the high impedance of the front end.
The article comes from:http://www.heturn.com.cn
-
07-23
How to choose the manufacturer of bathroom mirror touch switch?
Some customers in the choice of bathroom mirror switch, do not know which brand to choose, making a headache. In fact, it is appropriate and easy to choose a reliable brand, but it may encounter some blocking situations from time to time. So now, Xiaobian will talk about what aspects to consider
-
07-23
How to install the touch switch of bathroom mirror?
1. Cut off the main power supply at home before using the equipment. Connect the black line and red line on the switch host to AC: 220V input, and the other black line and blue line to AC220V output and connect to the lamp.2. Use screws to fix the host at the position where the LED cursor wi
-
07-23
What are the advantages of bathroom mirror touch switch?
The advantages of mirror contact switch are as follows:1. It adopts imported intelligent IC electronic control and excellent technology. It has no arc, can be operated with wet hands and does not bear human electric shock.2. The equipment is made of high-strength tempered glass panel, wh
-
07-23
What should I pay attention to when using the bathroom mirror touch switch?
There is a switch in the contact switch of the bathroom mirror that just needs to be opened and it will ring. This is a kind of sound of lighting. It will produce "heat" together and burn out the switch after a long time. Check whether the screw fastening the wire is loose; The tension