How to deal with the PAD issue in a PA?

[nxing]

PAD for PA

Hello everybody:

I am a analog VLSI design engineer and I am now designing a Power Amplifier. Now, I need the answer for the following question:

The power is about 0.1 Watts with power supply of 3V, I am wondering how to deal with the PAD issue, I mean can we just put one pad or we need several pads? If we need several, how to decide the number?
Thanks for your help!

Best Regards,

 

[springf2000]

Re: PAD for PA

according to my experience of use the PA transistor,it is several PADS

 

[nxing]

PAD for PA

Hi Springf2000

Thanks for your reply!
Is it possible that I just use metal to connect outside without pads?

Regards,

 

[bouchy]

Re: PAD for PA

In order to figure out how many pads to use you need to answer these question?
1-How much current is flowing through you device from Vdd or Vcc?
2-How much power are you delivering (Pout)?
3-Is your design bandwire (BW) sensitive? Meanings if you change the length of you BW say from 20mils to 80mils, does that change the performance of the circuit? And by how much?

The key thing to remember is that L // L = 0.5L + some mutual coupling between the two. For example by using 2 BW (meaning you will need 2 pads):
1-the total inductance associated with the BW will be (ideally) divided in half.
2- by letting the total Icc or Idd flow through 2 parallel BW instead of only one BW, you will not be stressing the BW. furthermore, as know, for each BW diameter there is an associated Imax that should not be exceeded; Pay close attention to that especially if you are designing for high power.
I hope my comments help.

Good luck