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How to generate a reference current of 5uA?

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surianova

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hi all!

i need to generate a reference current of 5uA. This 5 uA must indepedent of power supply, process and temperature. Any idea or journal i can refer to generate this current? Thanks in advance.
 

yxo

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Reference current

There are four type of current sources. They are proportional to absolute temperature (PTAT); gm-matching; temperature independent;and currents with a negative temperature coefficient (TC). Find in google any of this current source. Or
https://www.freepatentsonline.com/ :)
 

surianova

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Re: Reference current

yxo said:
There are four type of current sources. They are proportional to absolute temperature (PTAT); gm-matching; temperature independent;and currents with a negative temperature coefficient (TC). Find in google any of this current source. Or
https://www.freepatentsonline.com/ :)

but all these is temperature dependence.
 

kumar123

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Re: Reference current

surianova said:
hi all!

i need to generate a reference current of 5uA. This 5 uA must indepedent of power supply, process and temperature. Any idea or journal i can refer to generate this current? Thanks in advance.

Chk if this post if it can help you
 

DenisMark

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Re: Reference current

It's very difficult in analog design to obtain PVT stable current reference with high tolerance.
U can make bandgap reference to get stable voltage with 2-3% tolerance (without trimming). To make stable current u can use off-chip resistor. It's one way.
The second one is using on-chip low TC resistor with trimming.
U can make voltage and current references separately or u can make compact circuit.
 

    surianova

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surianova

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Re: Reference current

DenisMark said:
It's very difficult in analog design to obtain PVT stable current reference with high tolerance.
U can make bandgap reference to get stable voltage with 2-3% tolerance (without trimming). To make stable current u can use off-chip resistor. It's one way.
The second one is using on-chip low TC resistor with trimming.
U can make voltage and current references separately or u can make compact circuit.

yes, thank you.i try already.. i found out it is quite ok to get constant current across power supply and temperature. But quite hard to get across process especially SS and FF.. i think that one might need trimmimg of resistors.
 

jluhzw

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Re: Reference current

Hello surianova
you can refer this paper in the following site, maybe it is useful.


I am also designing a current reference with invariant for process and temperature.
I also think it is not very difficult for design a current reference with invariant for
temp and power supply.
 

babbage

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Reference current

PTAT current+NTAT current
 

codec

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Re: Reference current

Consider I1=Vbe/R, I2=VT/R and then mix I1 and I2 with proper coefficients
 

wolf001

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Reference current

A ideal refrence current,;babbage
, Can the PTAT current+NTAT current realize it?
 

gavin168

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Reference current

Is there any good idea to make current reference with indenpendence of Temp and Process. all component should be on-chip. It is better to not use resistor, because it is too hard to make a precise resistor in silicon.
 

anilshrirao

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Re: Reference current

since its very low current and need stabilization for various parameter. u must use band gap reference to design design current mirror....
 

mvishwakreddy

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Re: Reference current

refer to sixth chapter in analog integrated circuit by ken martin
 

kumar123

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Re: Reference current

surianova said:
hi all!

i need to generate a reference current of 5uA. This 5 uA must indepedent of power supply, process and temperature. Any idea or journal i can refer to generate this current? Thanks in advance.


chk if these can help you
 

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    surianova

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yxk

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Re: Reference current

kumar123 said:
surianova said:
hi all!

i need to generate a reference current of 5uA. This 5 uA must indepedent of power supply, process and temperature. Any idea or journal i can refer to generate this current? Thanks in advance.


chk if these can help you


thanks
 

Sadegh.j

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Re: Reference current

Use a band gap reference circuit for your supply.
 

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