| 摘要 |
PURPOSE:To make it possible to increase sufficiently a threshold level viewed from an input terminal side by providing an additional diode besides an off-buffer circuit and charging-discharging transistor. CONSTITUTION:Between the base of output transistor TR2 and the collector of charging-discharging transistor TR3, diode D2 is provided. Consequently, when the voltage at input terminal 1 is increased from the low ''0'' level voltage to the high ''1'' level voltage, the base potential of phase-division transistor TR1 required for phase-division transistor TR1 to change from the off-action state to the on-action operation is sum (VCE3+VD2+VBE1) of collector-emitter voltage VCE3 of TR3, potential difference VD2 by diode D2 and base-emitter voltage VBE1 of TR1. In comparison with the conventional value, this potential is higher by potential difference VD2 by diode D2. Therefore, the threshold voltage viewed from the input terminal 1 side is higher. |
