Sequencing ADM1085 - ADM1088

Question

Hello,,, I just hope i am not going against the rules of this site. i want to use ADM1087 in my project. I need a delay between pulses. this is a very simple scheme, but it does not work in practice. 
 maybe i do something wrong? 
 Vin=5Vptp, Vofset=0 
 
 Thanks very much

Ren · Accepted Answer

Hi Max, 
 What do you mean the circuit is not working? 
 two things i can think of that may have caused the circuit not behaving as you would expect: 
 
 the ADM1087 has an open-drain output so the output needs a pullup resistor. is i not drawn in your schematic but maybe you have it. 
 If you want to create a delay on a switching signal then this may not work as you expected. The ADM1087 will only create a delay if the input changes from low to high and remains high. If the input changes state before the output toggles then the timer would be reset.And there is little delay from input goes low to output goes low. 
 
 Ren

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Sequencing> ADM1085 - ADM1088