Bond Pads ... Do they have symbol?
Have anyone come across symbol for bond pads?
Ain't bond pads just metal connections in layout?
How does bond pad affect RF designs?
Cheers,
noobie
Hi noobie,
I have not come across symbols for bondpads so far. Except in papers, recently.
Bondpads are two of two different types.
GND pad: All metal layers are shorted together down to the substrate
SIGNAL pad: none of the metal layers are shorted together...The signal probe is placed on the top metal.
Probably metal 1 is used as the ground layer to go around the layout.
a signal pad acts like a capacitor....top plate is top metal and bottom plate is metal 1.
So this capacitor loads the circuit.
Hi,
PCB layout designer call it as plain "footprint". It is just a metal normally copper bonded into a dialectric that provide connection between PCB trace and component by using little amount of solder paste.
For microwave application pads dimension is very crucial because the wavelength is very small and the physical properties of the medium is affecting the microwave signal.
This is the reason that such passive component become smaller(1005) at microwave frequency. But don't worry IPC standard already established a required dimension for every component that you should use in designing PCBA and you can even download libraries so you don't need to design it by yourself .
ADS is using this symbol "SMT_Pad", we can edit its properties and generate it in layout
Goodluck...
it can be consider as a parellel capacitor to ground, and the value my be between 100 ~ 600f, depend on the pad structure.
btw: you can get the detail information from your foundary, such as TSMC et al.
Agilent ADS kits has some BondPad Models use them to see the effetc!