If input signal is 3V (1) on the base, OUT is around 0V (0). When input is 0V (0), OUT will be 3V (1). Application is inverting an arduino laser sensor signal before arriving to the digital port. A diode is used to protect the photo-transistor, connected to the base. When the laser is not blocked, signal is aways 3V from the receiver. When there is a detection, the signal will be HIGH, else LOW. Searching for a single port inverter IC but not found yet. Design not testes yet and trying to select an adequate transistor. Problably a BC537 or 547 but not sure. Help very much appreciated. Thanks.
