| 摘要 |
<p>PURPOSE:To strengthen a circuit against a noise, and also, to constitute it so that it can be combined with a three-state type output circuit by providing differential transistors whose thresholds are different from each other, and obtaining the appropriate criterion level of a differential amplifier circuit. CONSTITUTION:In an input circuit 10, the differential transistor Q11 of an input side receives the input signal WIN of minute amplitude transferred through a data bus 3 by a gate, and the differential transistor Q12 of a reference side receives the reference potential VREF of the same potential as an intermediate potential power source VTT corresponding to roughly the intermediate potential of a high potential side power source VCC and a low potential side power source VSS by a gate. In such a case, thresholds of these transistors Q11 and Q12 are set to values being different from each other. Accordingly, for instance, output logic in the case the input signal VIN and the reference potential VREF are equal to each other is determined unequivocally from the size relation of the threshold. In such a manner, in the case the data bus is in high impedance, the uncertain problem of the output logic in (VIN=VREF) can be avoided, and resistance against ringing and an external noise, etc., can be improved.</p> |
