Patent attributes
An exemplary programming circuit (40) includes an input terminal (42) configured for receiving an external high voltage signal, a driving circuit (20), a switch circuit (43) connected between the input terminal and the driving circuit, and a feedback circuit (45). When the external high voltage signal is larger than a normal value thereof, the feedback circuit outputs a first control signal to turn off the switch circuit. When the external high voltage signal is less than the normal value thereof, the feedback circuit also outputs the first control signal to turn off the switch circuit. When the external high voltage signal is equal to the normal value thereof, the feedback circuit outputs a second control signal to turn on the switch circuit.
