| 摘要 |
PURPOSE:To enable a component to be changed in flashing period keeping it unchanged in type by a method wherein an AND gate, which computes the logical product of an input signal and a rectangular wave output generated from a rectangular wave generating circuit, and a light emitting diode which is turned ON or OFF basing on the output of the AND gate are provided. CONSTITUTION:A reference voltage generating circuit 107 generates a reference voltage for an input signal 1E, and a voltage difference between the reference voltage and the voltage of the signal 1E is obtained through a difference detector 109. In the result, an output signal 1F of the difference detector 109 is a voltage which varies according to whether the input signal 1E is kept at an intermediate level or at a normal level. The signal 1F is inputted into a rectangular wave generating circuit 108, and a slow rectangular wave is outputted as an signal 1G when a the input signal 1E is set at an intermediate level and a fast rectangular wave is outputted as an signal 1G when the input signal 1E is set at a normal level, and the signal 1G is inputted into an AND gate 111. The input signal 1E is converted into an output 1H through the AND gate 111 to enable a light emitting diode to start a flashing operation. |
