noise analysis for a low-noise opamp

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_SquiD_

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some measures needed ...

Hi there, guys ! I have to make this noise analysis for a low-noise opamp. From where could I get the following:
- the flicker noise coefficients KF for the NMOS and the PMOS;
- gamma - the bulk transconductance parameter;
- the surface potential at strong inversion;
all of this for the gpdk .180nm technology ?

Thanks in advance.


P.S.: Some additional information about the noise analysis of a LNA that may come on handy it would be welcomed too.

_SquiD_
 

Re: some measures needed ...

Hi

For BSIM models AF,KF will be available in the model definition/model card.

For gamma,Phi @ strong inversion, U can use SPICE teststep to extract them. by this way u r calcualtions won't deviate much from simulaiton.

For LNA, Please ensure that u r using models with NQS included. Plot the noise/gain circles and do the matching.

thanks,
 

Re: some measures needed ...

Blackuni said:
For BSIM models AF,KF will be available in the model definition/model card.

Where will I find this because I didn't manage to find them anywhere ? Be more specific please.

Blackuni said:
For gamma,Phi @ strong inversion, U can use SPICE teststep to extract them.

For LNA, Please ensure that u r using models with NQS included. Plot the noise/gain circles and do the matching.
What is this SPICE teststep ? What about NQS (it's a shortcut for ...)?

_Squ!D_
 

Re: some measures needed ...

Hi,

1) Here is a sample Hspice model card( i found this handy), i mean the MOS model parameters provided by foundry. I hope u find it!! . Also please check your foundry documentation
******************
.MODEL nch3 NMOS ( LMIN = '0.18E-06-dxl3'
+NLEV = 3 AF = 0.9065 KF = 3.564E-24
+LMAX = 2.1E-05 WMIN = '1.00E-06-dxw3' WMAX = 0.000101
+LEVEL = 49 TNOM = 25 VERSION = 3.1
********************

2) write a spice netlist or draw a schematic for single nmos or pmos, with voltage biasing in such a way tht your MOS will be in strong inversion/saturation(vgs=vth + >70mv), do operating point analysis in any spice tool. Refer the documentation for that tool to find way to dump these values(gamma,Phi @ strong inversion)
you can also surf...there are literature explaining this in detail.(hint for searching.."MOSFET parameter extraction using spice for hand calculation)

3) NQS --> non quasi static effect, to be simple, its the delay in gate voltage change to corresponding channel charge.

Hope i am specific. Please let me know if i am not.. let me try again.

Thanks,
 

Re: some measures needed ...

Isn't there a way to determine these values using Cadence IC5033 ?
 

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