vincentspm
New Member
Hi,
I'm gonig to design a timer with about 5.5 hour OFF and 13 sec ON.
TRIED:
1)i had try is using 555 timer and (3 x 4017) counter
2)5 hour = 5*3600 = 18000s
3)Setting Astable 555 timer, R1 and R2 = 100k and C=0.0001F,
get 0.05Hz clock, 13s ON, 7s OFF
4)cascaded 3 x 4017 counter,connect to output pin 11,
cycle time(20) multiply 1000(3 x 4017 counter) = 20000s = 5.5Hour
PROBLEM FACE:
The high output from 3rd 4017 counter will base on 2nd 4017 clock,
there 2000s ON and 18000s OFF.
Any one can give me a help on this, i need to ON in less than 1 minute??
I'm gonig to design a timer with about 5.5 hour OFF and 13 sec ON.
TRIED:
1)i had try is using 555 timer and (3 x 4017) counter
2)5 hour = 5*3600 = 18000s
3)Setting Astable 555 timer, R1 and R2 = 100k and C=0.0001F,
get 0.05Hz clock, 13s ON, 7s OFF
4)cascaded 3 x 4017 counter,connect to output pin 11,
cycle time(20) multiply 1000(3 x 4017 counter) = 20000s = 5.5Hour
PROBLEM FACE:
The high output from 3rd 4017 counter will base on 2nd 4017 clock,
there 2000s ON and 18000s OFF.
Any one can give me a help on this, i need to ON in less than 1 minute??