| 摘要 |
<p>PURPOSE:To obtain a triangle wave signal having a stable frequency by setting a charging circuit of a capacitor while a terminal voltage of the capacitor is lower than a reference voltage fed to a comparator circuit thereby setting a generated voltage from a reference voltage generating circuit to the 1st reference voltage switchingly. CONSTITUTION:When a terminal voltage VC of a capacitor CT reaches a voltage VH, an output of a comparator circuit 13 is inverted into a high level and switch elements S1, S2 are turned on. Thus, in this stage, a reference voltage Vref fed to the comparator circuit 13 is expressed as R1XI=VL, the capacitor CT is discharged via the switch element S1 and the 2nd constant current circuit 12 and the voltage VC is decreased in proportion to a time (t). When the terminal voltage VC of the capacitor CT reaches the reference voltage VL, the output of the comparator circuit 13 is inverted again into a low level and the capacitor CT is subject to charging control. Thus, a triangle wave is generated at the terminal of the capacitor CT succeedingly.</p> |
