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For instance, in this CD4075, when any one of the 3 inputs is 1 (say 5V), then the output is constant 1 (say 5V) as long as the input value is 1.

I want a similar IC which is capable of outputting constant 1 for about 10 seconds (or <1 min) when input is supplied. The output should remain constant even if the input is returned to ZERO (0). The output maybe any value less than 9V.

Please suggest the appropriate IC which is capable of performing the above desired logic.

enter image description here

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    \$\begingroup\$ A monostable 555 is what you're looking for. \$\endgroup\$ 2 days ago
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    \$\begingroup\$ Please add any unstated additional requirements (like the fact that you want the solution to work without capacitors) to the question, to prevent apparently correct answers being rejected. \$\endgroup\$
    – StarCat
    2 days ago

3 Answers 3

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This classic circuit is a monostable multivibrator. Of which the most well-known chip is the 555.

This is from Art of Electronics 3ed, p460: enter image description here

Another well-known chip is the LTC6993, good for up to about 30 seconds: enter image description here

If, for whatever reason, you want a purely digital chip, consider a very small microcontroller such as an ATTiny with the appropriate trivial program. Many microcontrollers have internal resonators and would need no external components.1

Honestly, any microcontrol would work. This particular one has an internal 128 kHz oscillator. This is from ATTiny13 datasheet enter image description here

If, for whatever reason, you can't use capacitors or inductors, you can do delays in the range of seconds to hours the really old way: a cam timer. Incredibly, are still in stock at some major distributors for about €50! (I've actually used one to soak test microprocessor designs!)

enter image description here


Note 1: Well, no external components other than decoupling capacitors. Horowitz and Hill say, (p 19),

enter image description here

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    \$\begingroup\$ maybe a CD4060? \$\endgroup\$
    – Kartman
    2 days ago
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    \$\begingroup\$ @NarT why is that ? The function you want will always need some sort of capacitor and resistor to set the timings. Unless you want to use a microcontroler with a mosfet switch (for heavy loads) \$\endgroup\$
    – Rahmany
    2 days ago
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    \$\begingroup\$ @NarT If you have additional requirements what is or is not an acceptable answer, add it to the question. \$\endgroup\$
    – Justme
    2 days ago
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    \$\begingroup\$ Now, Im looking for IC without capacitor. any IC requires a capacitor believe me. You won't get away from placing even a 100n at the Vcc/VDD pin of any IC. \$\endgroup\$ 2 days ago
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    \$\begingroup\$ @NarT Why do you want to avoid capacitors? The only real alternative, if you can get away without a decoupling cap (you can't), would be to use RL circuit for your timing, and an inductor would be even bigger than a capacitor... (Crystals and ceramic resonators are also capacitors, so I'm assuming you don't want those either.) \$\endgroup\$
    – Hearth
    2 days ago
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There exists special timer ICs, for example Analog devices (formerly Linear) TimerBlox. Take a look at LTC6995.

If not that, ANY MCU will happily do that job for you and more. Take a look at ATtiny, PIC, STM32 and the like.

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Program a PICAXE. My friend asked for something similar for Halloween decorations and that is what I used. Main investment cost is the programming cable which is $30CAD.

I didn't want to learn BASIC so I used the flow chart software to program it.

You aren't going to find an non-MCU IC that just happeens to do exactly what you are asking for.

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