For the set-top box light touch switch, the most important electronic device is the circuit and power supply. These problems are a relatively important process. In addition, the composition and use of Dongkun Electronics Technology Co., Ltd. need professional and technical personnel to explain to you. This is very important, but also a state that everyone needs. Please understand in detail. And learn this knowledge.
The light touch switching power supply is composed of main circuit, control circuit, detection circuit and auxiliary power supply.
1. Impulse current limit of main circuit: limit the impulse current of input side at the moment of switching on the power supply. Input filter: Its function is to filter the clutter existing in the power grid and hinder the local clutter feedback back to the power grid. Rectification and filtering: Direct rectification of AC power supply in power grid into smooth DC power supply. Inverter: Converting rectified DC to high frequency AC, which is the core part of high frequency switching power supply. Output Rectifier and Filter: According to the need of load, provide stable and reliable DC power supply.
2. On the one hand, the control circuit sampled from the output terminal, compared with the set value, and then controlled the inverters to change their pulse width or pulse frequency, so as to stabilize the output. On the other hand, according to the data provided by the test circuit, the protection circuit identifies and provides various protection measures for the power supply by the control circuit.
3. The detection circuit provides all kinds of parameters and instrumentation data that are in operation in the protection circuit.
4. Auxiliary power supply realizes software (remote) start-up of power supply, and supplies power for protection circuit and control circuit (PWM chip).
This is the basic circuit and power supply problems of the set-top box touch switch. All the problems that should be paid attention to when using them are listed. Please read them in detail.
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