Photo chopper circuit

摘要

The photo chopper circuit comprises a photo chopper, a power switch, an overvoltage detection/control device, and a protective diode. The photo chopper detects the turning angle of the motor of the motor drive and sends the detected signal to the voltage detection terminal (SENSOR) of a satellite antenna allocator. The photo chopper has one end connected through the power switch to the VCC terminal of the satellite antenna allocator and an opposite end connected to the positive terminal of the protective diode. The negative terminal of the protective diode is connected to the ground terminal (GND) of the satellite antenna allocator. The overvoltage detection/control device is connected to between the internal circuit of the power switch and the positive terminal of the protective diode, and connected to the VCC terminal and voltage detection terminal (SENSOR) of the satellite antenna allocator. If the output voltage of the photo chopper is connected to the high-tension lines (M1, M2) of the satellite antenna allocator for driving the motor drive, or its power supply voltage is connected to the high-tension lines (M1, M2) of the satellite antenna allocator for driving the motor drive, the power switch will be switched off by the overvoltage detection/control device to turn off the photo chopper so as to protect the photo chopper from damage. If the power supply voltage and output voltage of the photo chopper are erroneously connected to the VCC terminal and ground terminal (GND) of the satellite antenna allocator, the protective diode prohibits reverse flow of voltage from damaging the photo chopper, and therefore the photo chopper is protected.