SELF-STOP CIRCUIT USING NONVOLATILE STORAGE ELEMENT CHARGE AMOUNT AS TIMER

摘要

A self-stop circuit includes a nonvolatile storage element (20), a write terminal (50) and an erase circuit (30) for controlling charge/discharge of the nonvolatile storage element (20). A judgment circuit (40) detects whether the charge amount accumulated in the nonvolatile storage element (20) is lower than a predetermined threshold value so as to detect a time elapse. This detects the product service life elapse so that operation of a product whose service life has expired can be stopped or modified. In order to recover the operation, the nonvolatile storage element (20) is charged or a cancel signal is supplied from an external terminal (53) to the judgment circuit (40) to realize this.