Working Principle and Common Dimensions of Light Touch Switch
Release time：2019-08-09 Clicks： Click
What are the working principles and commonly used dimensions of light touch switch, and what are the specific details? Here we will give you a detailed introduction in this respect.
Today's content is related to the analysis of light touch switch and waterproof light touch switch, including the abnormal handling of light touch switch, the working principle and common size of light touch switch, the analysis of advantages and disadvantages of light touch switch, the introduction of attention, selection criteria and current situation analysis of water proof light touch switch.
Firstly, the light touch switch is introduced. Firstly, the working principle and common size of the switch are clarified, and the matters needing attention are introduced.
The working principle of light touch switch:
220V AC passes through the bulb H and rectifier bridge and becomes DC pulsating voltage; as forward bias, it is added to thyristor VS and R branches. In the daytime, when the brightness is greater than a certain degree, the photodiode D presents a bottom resistance state of less than 1K, which cuts off the triode V. Its emitter has no current output, and the one-way thyristor VS is blocked because of no trigger current. At this time, the current flowing through the bulb H is less than 2.2mA, and the bulb H cannot emit light. Resistor R1 and voltage regulator diode DW make the bias voltage of triode V not exceed 6.8V and protect triode. At night, when the brightness is less than a certain degree, the photodiode D presents a high resistance state (> 100K), which makes the transistor V forward conducting. The emitter has a voltage of about 0.8V, which makes the thyristor VS trigger and turn on, and the lamp H emits light. RP is a brightness selection element for switching in the morning or evening.
Touch switch is the fourth generation switch product developed with the development of electronic technology. The earliest volume is 12 mm * 12 mm, 8 mm * 8 mm, and now it is 6 mm * 6 mm. There are three types of product structure: vertical, horizontal and horizontal with ground ends. Now there are two kinds of combination (3M, 4M, SM, 6M, SM) and potentiometer light touch switch combination, which meet the requirements of various domestic electronic products. Now there are fifth generation switch - thin film switch, which has the same function as touch switch. It is mainly used in electronic instruments and CNC machine tools, but it has large resistance and poor handle. In order to overcome the phenomenon of poor hand feel, there are also contact reeds installed in the membrane switch instead of using silver layer as contact point.
Due to the increasing market demand for light touch switches, there are many types of light touch switch specifications. Small light touch switch specificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecificspecific4mm*4mm*4mm*4mm*4 mm*4 mm*1.6, 4mm*4 mm*4 6 mm*1.6 6 mm, 4mm*4mm*4mm*6mm mm*4 mm*4.3mm mm*4 mm*4 mm*4 mm*4.6mm*6 mm mm*4 mm*2.6 mm mm mm mm, 4 4 4 mm mm*4.5 mm*4 mm*4 mm mm*4 4 mm*4 mm mm*4 4* 5, 4.5 mm * 4.5 mm * 6, 4.5 mm * 4.5mm*7mm, 4.5mm*4.5mm*8mm, 4.5mm*4.5mm*9mm and other specifications.