PURPOSE: To provide the magnetic head disconnection detecting circuit with high operational margin and timing margin and with superior high frequency characteristic.
CONSTITUTION: A magnetic head disconnection detecting circuit ED is basically provided with a first differential circuit consisting of transistors T1 and T2 receiving an inversion input signal VIY or a non-inversion input signal VIX of a light amplifier, a second differential circuit consisting of transistors T3 and T4 receiving the inversion input signal VIY or the non-inversion input signal VIX, a third differential circuit consisting of transistors T5 and T6 receiving a non-inversion output signal VOX of the light amplifier or a reference potential VR, and a fourth differential circuit consisting of transistors T7 and T8 receiving the reference potential VR or the inversion output signal VOY. Thus, the required operational point is given to each differential circuit, intentionally delaying the state transition of transistors T6 and T7.
HATANAKA NORIAKI
HIRAI TOMOAKI
YOSHINAGA MAKI
NAGAYA YUJI
