RF simulation using Pspice - RF Cafe Forums

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ARJ

Post subject: RF simulation using Pspice

Posted: Mon Oct 29, 2007 5:20 pm

Lieutenant

Joined: Mon Oct 29, 2007 5:07 pm
Posts: 4

Hi all,

I am trying to simulate BGA 427 Chip by Infineon. I was using ADS but as infineon doesnt have a model for ADS, switched over to Pspice.

I was wondering can i simulate the model using the transistor's parameter given in the datasheet. I am using Pspice's 2N2222 Transistor as a replacement.

http://www.ortodoxism.ro/datasheets/inf ... bga427.pdf for the datasheet.

My initial results are Gain of 46 dB at 200 MHz, 36 dB at 1 GHz.

Thanks

ARJ

Feng

Post subject:

Posted: Tue Oct 30, 2007 1:14 pm

Colonel

Joined: Sun Mar 19, 2006 5:25 pm
Posts: 30
Location: Burnaby

Hi ARJ,

I am not sure what kind of simulation you are going to do in ADS, but for certain simulations such as S-parameter simulation, you may think about BGA427 as a 2-port component, and use 2-Port S-parameter file component, which you can find it in Data Items. However, this method has many limitions due to limited data given in the data sheet.

Or you may try to build a model according to the Transistor Chip Data T1 on the data sheet. The possible models are in the Device BJT components in ADS. There may be one suit for your application.

ARJ

Post subject:

Posted: Fri Nov 02, 2007 4:48 pm

Lieutenant

Joined: Mon Oct 29, 2007 5:07 pm
Posts: 4

Thanks Feng

sorry for being late. I have to renew my Agilent ADS ID and that took time.
Now i have got the ID i am ready to try this out.

I guess building a model would be a good idea. The circuit isnt that big. Moreover i need a good simulation. U mentioned to go to Device BJT components. I have no clue as i am only a beginner. Could u please let me know how to do that.

Thanks

Anil

Feng

Post subject:

Posted: Sat Nov 03, 2007 2:01 am

Colonel

Joined: Sun Mar 19, 2006 5:25 pm
Posts: 30
Location: Burnaby

Hi ARJ,

You are welcome. The components with a square frame in the Devices_BJT may be the candidates for BJT modeling. You may try the component of BJT_Model and verify it first by simulating it in a given situation. After it is proved to suit for the required condition, then you can do what you want by taking advantage of this transistor model.

I hope it can help. Good luck.

ARJ

Post subject:

Posted: Thu Nov 08, 2007 6:52 pm

Lieutenant

Joined: Mon Oct 29, 2007 5:07 pm
Posts: 4

Hi Feng,

Thanks for your advice.

The amplifier I am modeling is a Si- MMIC BGA 427 amplifier. Can i model it using a BJT given in ADS. The reason for this question is that i tried modeling the amplifier according to the parameters given in the datasheet. http://www.ortodoxism.ro/datasheets/inf ... bga427.pdf

I used the Devices_BJT from the component list.
The results are totally different. The amplifier doesnt amplify the signal at all.

Could u please help me out.

Thanks
Anil

Feng

Post subject:

Posted: Thu Nov 08, 2007 8:33 pm

Colonel

Joined: Sun Mar 19, 2006 5:25 pm
Posts: 30
Location: Burnaby

Hi ARJ,

I review the datasheet again and list considerations as following.

1. Only parameters of transistor T1 and C-E diode are given in the datasheet, but in fact there are two transistor T1 and T2 in the package. So you may suppose that they have the same parameters when you were modeling. However, both we can not make sure they are identical.

2. Parasitic parameters may play an unignorable role in RF circuit. so you may include them, which is given just above the T1 chip data in the datasheet.

3. Verify your model first before you start your circuit simulation. Meanwhile, pay close attention to what kind of simultor you used. It depends on your goals.

I hope it is helpful.

ARJ

Post subject:

Posted: Sun Nov 11, 2007 9:55 pm

Lieutenant

Joined: Mon Oct 29, 2007 5:07 pm
Posts: 4

Hi Feng,

Does the capacitors and inductors due to Package should be included in the parasitics??

and does those S- parameters are for the Transistor or for the whole chip??

thanks for all your help....
Anil

Feng

Post subject:

Posted: Sun Nov 11, 2007 10:13 pm

Colonel

Joined: Sun Mar 19, 2006 5:25 pm
Posts: 30
Location: Burnaby

Hello ARJ,

You are welcome.

For a precise modeling or high frequency simulaiton, parasitic effect should be counted in. In my opinion, I think the S-parameters are for the whole chip because they are measurable and can be measured.

Posted 11/12/2012

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