The light touch switch is often used in the set-top box. In addition, it must have some special functions in the circuit and protection frequency. What specific problems are needed?
Light touch switch low voltage rectifier filter circuit: after high frequency transformer step-down start pulse voltage to use the same diode rectifier and filter and capacitor, and the rectifier part using ac impedance of capacitance also cannot have the too big, it won't be able to filter out the high frequency ac components, so the selection of capacitance larger capacity, not only have low ac resistance, can also see 1, 2, a large volume of magnetic core inductance coil, filter out high frequency components of communication together with the filter capacitor, guarantee the output pure dc. Press the shrapnel to connect the printed circuit.
What are the special features of the touch switch?
Short circuit instantaneous protection: the protection current is related to the rated working current of the electronic tripping device, and its setting current is 16In 15% and the operating time t3 0.1ms.
Short circuit time delay or fixed time protection: the protection current is related to the rated working current of the electronic tripping device, which can be adjusted on the setting current panel (6 ~ 12Ir1).
That is, in addition to the conventional thermal protection current can be set according to the load power, overcurrent protection setting current can also be adjusted on the panel (distribution load adjustment range is 3 ~ 6Ie, motor load adjustment range is 6 ~ 12Ie).
The special functions used by the light touch switch must be learned from it, and these problems can help us in our use.
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