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Ricky Chen Community Member Offline Posts: 49	Package Inductance for 10 GHz range operation Oct 05^th, 2011, 8:13am Dear friends, Can anybody tell the best package available for 10 GHz RF signal operation ? The lowest inductance is desirable. Bondwire inductance can be reduced for smaller package but what about LEAD inductance ? What PCB material should be used and what is the constraints on PCB trace for proper operation at 10 GHz?
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rfcooltools.com

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Re: Package Inductance for 10 GHz range operation
Reply #1 - Oct 10^th, 2011, 11:10pm

Ricky-chen,

if price is no option when a flipped chip on rodger4003 substrate will probably be pretty good.

More practically what kind of signals are these 10GHz are they tones or are they broad band up to 10GHz. The reason I inquire is that the answer to this will determine if a low impedance at high frequency is needed or if the impedance at high frequency of a bondwire can be resonated or transformed into something more benign.

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Ricky Chen Community Member Offline Posts: 49	Re: Package Inductance for 10 GHz range operation Reply #2 - Oct 11^th, 2011, 6:27am Thanks for your reply It is Broad Band. I think tuning is not perhaps an option. By the way what is the cost of rodger4003 substrate ? What it actually helps ? -Ricky
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rfcooltools.com Senior Member Offline Posts: 159	Re: Package Inductance for 10 GHz range operation Reply #3 - Oct 28^th, 2011, 10:09pm Ricky Chen, rogers is about 5 to 10 time more expensive than fr4. Its controlled under tighter process parameters more predictable t-lines and even strip-line filters epsilonR is different and is stable over temp. You can make do with fr4 depending on your application. http://rfcooltools.com
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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: Package Inductance for 10 GHz range operation Reply #4 - Oct 29^th, 2011, 11:57am QFN packages are commonly used up to 5GHz, and perhaps are viable to 10GHz. Need to look at the package model and determine the reactive elements. chip on board with a specialty dielectric are another possible but if you want a typical chip in package on pcb i would look at the QFN
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Ricky Chen Community Member Offline Posts: 49	Re: Package Inductance for 10 GHz range operation Reply #5 - Nov 16^th, 2011, 5:19pm Thanks loose-electron, Can you tell us the cost of Chip on board. I mean how much costlier it will be than the FR4 PCB. I think one can also mount all discrete components on Chip on board. Do you think FR4 PCB with QFN package will work well till 5 GHz.
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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: Package Inductance for 10 GHz range operation Reply #6 - Nov 16^th, 2011, 9:39pm keep the traces short and include the board parasitics in your model and hit the simulate button!
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Ricky Chen Community Member Offline Posts: 49	Re: Package Inductance for 10 GHz range operation Reply #7 - Nov 16^th, 2011, 9:44pm loose-electron wrote on Nov 16^th, 2011, 9:39pm: keep the traces short and include the board parasitics in your model and hit the simulate button! Simulate button for what simulation ? Can you mention something more about Chip on Board if u have experienced using that
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loose-electron

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Re: Package Inductance for 10 GHz range operation
Reply #8 - Nov 18^th, 2011, 9:02am

the parasitics of your board, the traces on the board, the RLC of the package can all be included into your simulation to determine if the methods proposed will work at the desired frequency.

You need to look up the coefficients of capacitance and inductance for the proposed PCB material and estimate those components in a simulation.

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