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delay cell using MOSFETS

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cmos_ajay

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Hello, I need to make a delay cell giving about 100 us delay using mosfets. The cell needs to have a trigger input. Can someone give suggestions ? Thanks and regards.
 

leo_o2

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Use large L and smalle W MOSFET to work as a resistor. And use Cgs of MOSFET as capacitor. RC will lead to delay.
 

andre_teprom

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If you´re working w/ ASIC design that amount of time seems very large and space needed will be very expensive to waste w/ that function.
Maybe is better you implement something based on counter solution.
 

kgl_13gr

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Do a search for current starved inverters. It is quite a large time however. You might have to use an on- or off-chip capacitor.
 

andre_teprom

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Timered solutions based on silicon dopping characteristics are highly affected by temperature and thus result is imprecise.
Maybe could be not the better choice.
Think about a syncronous based solution.

+++
 

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