| 摘要 |
<P>PROBLEM TO BE SOLVED: To automatically and surely reset a microcomputer in the case of microcomputer latch without adding any special configuration for watch dog. <P>SOLUTION: In a reset circuit 100 of a microcomputer 200 to which a clock signal is input from a crystal oscillation circuit using a crystal oscillator Xtal, the microcomputer 200 including a GPIO terminal 201 whose output periodically changes between High and Low is configured so as to be automatically put in a reset state when the input of the clock signal is stopped, and the reset circuit 100 is configured to smooth the output of the GPIO terminal 201 by using a capacitor, and to, when a smooth voltage is set to an intermediate potential between High and Low, generate resistance which is smaller than the negative resistance of the crystal oscillator Xtal, and to apply the resistance to the crystal oscillator Xtal, and to, when the smooth voltage is set to High or Low, generate resistance which is equal to or more than the negative resistance of the crystal oscillator Xtal, and to apply the resistance to the crystal oscillator Xtal. <P>COPYRIGHT: (C)2013,JPO&INPIT |
