| 摘要 |
PURPOSE:To obtain a circuit having a function equal to that of a conventional function with a smaller number of components than the conventional number by providing a gate circuit connected to each collector of two PNP transistors (TRs) and inverting its output only when each collector current changed based on the input voltage is both smaller than the current of a current drawing circuit. CONSTITUTION:A circuit comprising TRs Q14, Q15 and a resistor R8 is a circuit applying a current to a differential circuit comprising TRs Q16, Q17 and a TR Q18 itself. The TR Q14 is a multi-collector TR and the ratio of a current I1 fed to the differential circuit to a current I2 fed to the TR Q18 is selected as I1:I2=3:2. TRs Q22, Q23 and a resistor R9 constitute a NOR circuit and resistors R6, R7 apply resistance division to the power voltage to give a trigger level VT. The TRs Q19-Q21 are NPN TRs of the same shape and the collector current of the TR Q19 is equal to the collector current of the TR Q20. |
