Patent ID: 9681092
Date: 2017-06-13
CPC Classifications: H03F,H04N

Claim:
1. A cable TV amplifier system, including: an amplifier module, including a body, at least one circuit board, a power connecting port, a signal input port, and a plurality of signal output ports, the at least one circuit board being installed inside the body and including at least one signal amplifier, and all the power connecting port, the signal input port, and the plurality of signal output ports being installed on the body and electrically coupled with the at least one circuit board; and a power converter, including an AC power input terminal, at least one DC power output terminal, and a switching power converting circuit, the AC power input terminal being used for inputting an AC voltage, the switching power converting circuit being used for converting the AC voltage to a DC voltage, and one of the at least one DC power output terminal being coupled to the power connecting port to provide the DC voltage, the switching power converting circuit including: a surge protection circuit coupled with the AC power input terminal; a bridge rectifying circuit having a first input terminal and a first output terminal, the first input terminal being coupled with the surge protection circuit; an energy transmission unit having a second input terminal, a second output terminal, and a control terminal, the second input terminal being coupled with the first output terminal of the bridge rectifying circuit, and the energy transmission unit transmitting energy to the second output terminal to provide the DC voltage under a control of a pulse width modulation signal applied to the control terminal; a feedback unit coupled with the second output terminal to generate a feedback signal according to the DC voltage; an AC voltage sensing circuit for generating a sensed level signal according to the AC voltage; and a control unit for generating the pulse width modulation signal according to the feedback signal, wherein, the control unit will stop outputting the pulse width modulation signal when the sensed level signal is in an abnormal state where the sensed level signal is higher than a first level or lower than a second level, the first level being higher than the second level.