| 摘要 |
PURPOSE:To produce a rectangular wave signal having a high frequency, by carrying out a charge/discharge switching of a capacitor through a circuit constitution that actuates a transistor at the nonsaturated region and thus setting the minor carrier accumulating time at zero. CONSTITUTION:The transistors (TR) Q10 and Q11 plus a constant current source I1 constitute a differential amplifier with a hysteresis caused to the reverse and reset action. In case when the TRQ10 conducts with the TRQ11 cut off, the reverse threshold voltage VE1 is high with a cut-off given to the TRs Q12 and Q14, respectively. Accordingly the current i2 of the current source I2 flows to the capacitor C1 to continue a charging. When the voltage VC of the capacitor C1 exceeds the voltage VE1, the differential amplifying circuit is inverted. Thus the reverse threshold voltage VE2 is set at a low level , and the TRs Q11 and Q12 conduct to start the flowing of the current i1 of the constant current source I1. Thus the TRQ14 also conducts to absorb the current i2 from the TRQ13 and the capacitor C1. When the capacitor C1 discharges to set the voltage VC at VE2, the differential amplifying circuit is inverted again to be put under a charging state. In such way, the charging and discharging are repeated in a high speed to deliver both the triangular and rectangular waves having a high frequency each to the terminals A and B. |
