4017 Reset Pin: min and max voltage?

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I want to add a hard reset button to a 4017 sequencer. Therefore, I am studying the datasheet to figure out the minimum and maximum voltage that can be applied to the reset pin (https://www.ti.com/lit/pdf/schs027). Page 4 of the datasheet shows the dynamic electrical characteristics, but the data on the reset operation somewhat confuse me. It shows Vdd of 5, 10, and 15 V, with nano second time limits. How should I interpret this? Can I simply use a 12V with a momentary switch? Or do I need a small circuit to limit the pulse time to not exceed the limit listed in the datasheet for the voltage used?

Thanks for your input!

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That’s the minimum pulse width, you should be OK with a button, I don’t think you can get a pulse in the ns range with a button…

The different VDD values are the voltage used to power the circuit, less voltage = slower operation = longer minimum pulse width.

The reset pulse should be close to the voltage used to power the IC, but the margin for what is a high for CMOS is quite large.

Explanation for low and high values you can find here :

In summary, a pulldown to ground, a push-button to +12V will work.

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like this i think

4017 reset
4017 reset944Ă—817 89 KB

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Yes, if you have other sources of reset you’ll need the diodes.

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Thanks for this information, this confirms my initial thoughts.

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Thanks @Dud, this is exactly how I have it hooked up now, so I will proceed with this route.

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