Need a timer
Preferably 4060 or 555 with some extra components
1)
Timer : 1 – 45Min
2)press to start ,a soft push should fire the timer .
This is because I don’t want the timer to fire always on power on.
example : if I am heating a glass of water with eggs via heater element
if power goes off and resumes , timer should not make heater on.
It has to make it on when I press soft switch.(just push,no latch)
After expiry sd make my device off ,relay is ok
now a days i am pulling my hairs in job ... just 8 hour weekends dont let me design these , again i like the idea of replacing c2 ,
if this works as needed ,it saves build time , also components..
expected operation
-power on , timer inactive
-press push, timer counts down , appliance is on
if
-power cut ,power resumes, obviously timer is inactive
In post #1 you say "It has to make it on when I press soft switch.(just push,no latch)", whereas in post #3 you say
"But the soft latch part is missing , w/o it the time will auto start w/o my permission". So which do you want? Latch or no latch?
soft latch is action [latching action in electronics ]..............
seems your circuit may fulfill this
Start timer switch is a pushbutton not a latch switch[like rocker switch post1], as if we use mechanical latch switch
timer will always start on power failure->resume
To meet your requirements fully I now think the circuit in the link won't do and a momentary switch plus a latching circuit will be needed.
Here's a possibility, simulated with LTSpice. I don't have a sim model of the CD4060 so used a CD4020 model instead. I've marked up the changes needed for use with a CD4060. An LED can be added as in the previous circuit if you wish.