| 摘要 |
<p>PURPOSE:To revise an oscillating frequency and a triangle waveform without replacing a timing resistor and a timing capacitor. CONSTITUTION:A charging current source section outputting a charge current to a timing capacitor CT is provided with plural current source sections 6-8 and charging current source control switched 22-24 selecting individually the validity/invalidity of an output of each of the current source sections 6-8. A discharging current source section outputting a discharging current to the capacitor CT has plural current source sections (transistor(TRs) 12-14) and is provided with discharging current source control switches 25-27 selecting individually the validity/invalidity of an output of each of the current source sections 12-14. A symmetrical triangle wave is obtained by selecting a charging current and a discharging current to/from the capacitor CT equal to each other and an asymmetrical triangle wave is obtained by selecting a charging current and a discharging current to/from the capacitor CT so as to be different from each other. Moreover, the frequency of a triangle wave is changed by changing only the current without changing a charge/discharge current ratio.</p> |
