open drain output

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vmore
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Last seen: 2 years 2 months ago
Joined: 2018-03-01 18:22
open drain output

Hello,

I want to use the open drain output feature on the chip. I have a one shot pulse generator attached to the pin that configured as a open drain with a pull up. I would like the pin output to be held high and switch to ground when the one shot pulse is given as an input to this pin. Is this the correct way to use this feature? I have attached a simple design file that recreates what I am trying to do. Can you point out what needs to be added to it in order to work correctly? Will I need to use an external fet switch to achieve desired behavior?

Attachment: 
Device: 
Device Number: 
46533v
pavloZ
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Last seen: 2 years 8 months ago
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Joined: 2018-01-31 12:50
Hi vmore, yes this is correct

Hi vmore, yes this is correct way to use one shot feature, but you should use open drain NMOS with pull-up resistor or PMOS with pull-down. So please choose desired case in the output pin settings (PIN20 of your design). Here is the waveform of the corrected design in the attachment. Yellow line input PIN4, blue line output PIN20.

Attachment: