| 摘要 |
PURPOSE:To obtain an oscillating frequency with very high stability against temperature change by utilizing the temperature dependancy of the forward voltage of plural transistors (TRs) or diodes so as to apply temperature correction. CONSTITUTION:A basic circuit of an emitter coupling type multivibrator is constituted by TRs 201, 202, 203 and 204 and TRs 218, 219, and a capacitor 250, and the temperature characteristic is compensated by TRs 205, 206, 207, 208, 216, 217, diodes 221, 222, 223, 224, 225, 226, 227, 228 and resistors 231, 235, 236. The resistance ratio is selected so as to obtain the relation of (alpha+alpha')/5alpha=R/R3, where alpha and alpha' are temperature coefficients of VBE, VBE(ON), R is the resistance value of the resistors 235, 236 and R3 is the resistance value of the resistor 231, allowing to compensate the temperature coefficient and eliminate the temperature dependance of the oscillated frequency. |
