PHILIPS TEA0678 Dual Dolby* B-type noise reduction circuit automatic music search with differential outputs mute handbook
TEA0678 is a bipolar integrated circuit that provides two channels of Dolby B noise reduction for playback applications in car radios. It includes head and equalization amplifiers with electronically switchable time constants. Furthermore it includes electronically switchable inputs for tape drivers with reverse heads. This device also detects pauses of music in Automatic Music Search (AMS) mode, with a delay time fixed externally by a resistor. The short-circuit proof output stage of the TEA0678 is differential and provides muting. The device will only output a signal when both NR channels are active.
