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current source circuit working in all corners

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fsm113

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I'm designing an ADC in 0.18um CMOS technology and I need an accurate and stable current source circuit for that. I have a couple of current sources designed by myself but all of them will fail in corner analysis. I want to make sure that my current sources will work in all corners. Could anyone here tell me about a current source which has been used in a tested and fabricated chip?
 

leo_o2

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Accuracy is failed for corner? What's accuracy requirement?
External resistor will help for accuracy improvement.
 

dgnani

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I'm designing an ADC in 0.18um CMOS technology and I need an accurate and stable current source circuit for that. I have a couple of current sources designed by myself but all of them will fail in corner analysis. I want to make sure that my current sources will work in all corners. Could anyone here tell me about a current source which has been used in a tested and fabricated chip?
what kind of corners are you running just process or voltage and temperature as well?

Depending on the type of corners and how strict the specs you can probably use a beta multiplier or a bandgap current reference, if neither design is enough then -as leo_o2 suggested- external components might be in order
 

houria

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I want a model of current source containing transistor CMOS.
pleaaaaaaase help me
 

fsm113

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I can not add any external resistor because I'm highly restricted by the design area. I need to reduce the process variation error as lower as possible. Right know the error is almost 90% which will cause a disaster in my chip!
 

rongo024

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As per I know none of the current source works well in all corner simulation. It will work well for a corner. To get a process tolerant current source you need to think about some feedback means calibration .
 

skowe26

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Hi, Have you considered trimming your current reference?
 

fsm113

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I don't know exactly what you mean by trimming.
 

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