The principle of light control and voice control of the smart voice control switch. In fact, the voice control smart switch contains many parts, and the operating principle of each part is different. However, as a whole, the voice control smart switch part is still light control and The part of voice control is the most important. In the voice control part, when there is a dynamic input of a satisfactory signal, the voice control part of the smart switch converts the dynamic signal into an electrical signal, and expands the signal through the transistor, so that the size of the signal can trigger the transistor.
The first stage and the second stage of the circuit are connected by resistors and capacitive elements, so it is called a resistance-capacitance coupling expansion circuit. The benefit of resistance-capacitance coupling is that because the front and rear stages are connected by capacitors, the DC circuits at all levels are not connected to each other, and the static operating points of each stage are independent of each other and will not affect each other. Planning and debugging bring great convenience. Moreover, as long as the coupling capacitor is selected satisfactorily, the output signal of the previous stage can be added to the input end of the next stage within a certain frequency range with almost no attenuation, so that the signal can be fully used.
The photosensitive part, as can be seen from the circuit schematic diagram, when the daylight or the brightness is greater than a certain degree, the resistance of the photosensitive resistor is very small, so for the photosensitive branch, it is equivalent to directly grounding, which is equivalent to connecting The back circuit is blocked from the front circuit, the transistor is always in the cut-off condition, the one-way thyristor will not conduct without trigger current, and the circuit will not work.
When there is no light, the photoresistor presents a high resistance value, which does not affect the signal transmission between the transistor and the transistor. At this time, the voice-activated part of the smart switch can play a role.
