| 摘要 |
PURPOSE:To prevent an off-delay timer from malfunctioning in application of electric power, by resetting a counting part the output of logical operation between an external signal and the output of a flip-flop circuit reset in the application of electric power. CONSTITUTION:On feed (a) of electric power, FF5 is reset and output Q' becomes ''1'' and is supplied to reset part 4 through exclusive OR circuit 6 to let reset part 4 generate an output, resetting counting part 2. Once external signal SP is input, FF5 is set and output Q becomes ''1'', but circuit 6 outputs signal SP and while counting part 2 stays reset, output ''1'' is passed through output part 3' to generate output signal (c) of the timer. As signal SP disappears, the signal from circuit 6 becomes ''0'', and consequently counting part 2 starts counting the output of oscillation part 1 and, when reaching a preset count value, generates its output to reset FF5, making the delay output from output part 3' into ''0''. |
