| 摘要 |
PURPOSE:To reduce the chip area required by a timer integrating circuit, by commonly using a resistance for feeding back voltage and another resistance for setting reference voltage and respectively fetching the feedback voltage of a constant-voltage circuit and reference voltage of a timer circuit from two voltage-dividing points. CONSTITUTION:When this timer integrating circuit is compare with conventional ones, this circuit has the same constitution as conventional ones have except that the resistances R1 and R2 for feeding back voltage and resistances R3 and R4 for setting reference voltage which are separately provided in conventional ones become common resistances R11-R13 in this circuit and the voltage dividing point (a) for fetching feedback voltage and another voltage dividing point (b) for fetching reference voltage respectively become the voltage dividing point (d) between the resistances R12 and R13 and voltage dividing point (e) between the resistances R11 and R12. When such a constitution is used, the constant voltage Vcc, reference voltage Vt, and timer time T can be determined from a formula. The length of the resistance body section of a contact section S becomes about a half as compared with conventional ones.
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