| 摘要 |
PURPOSE:To obtain a triangle wave signal having a minute leading time by providing a delay circuit utilizing saturation of a PNP transistor (TR) in a negative feedback loop formed between the input and output of a TR. CONSTITUTION:When a power supply Vcc is fed, TRs Q4, Q13, Q14 are turned on and a reference voltage VREF is obtained. A TR Q9 constitutes a current mirror circuit and when the TR is turned on, a bias voltage is applied to a TR Q3. As a result, a capacitor CA is charged. Since the PNP TR Q5 is turned on while being saturated deeply, the TR Q3 keeps forcibly the on-state even when a TR Q6 is turned off to keep the charging to the capacitor CA. When the voltage of the capacitor CA rises up to a prescribed value, the TRs Q5, Q3 are turned off and the voltage across the capacitor CA is decreased gradually. |
