| Author |
Message |
ASIC
Joined: 18 May 2001
Posts: 208
|
 17 Sep 2001 5:19 |
|
|
|
Guys,
In the next couple of weeks I will face some problems that they don't teach you about in school. Here is the first one....
How much current can a bonding-wire take (100 micron pad size)? When to switch to double-bonding? How many pins should be assigned to VCC and GND? Any rule of thumb?
ASIC
|
|
| Back to top |
|
 |
bastos4321
Joined: 01 Jan 1970
Posts: 327
Helped: 22
|
| 17 Sep 2001 19:57 |
|
|
|
Hi Asic,
I use about 50mA/Pad for typical pads. The double bounding is necessary if you need to lower the bond indutance. That depends on the type of circuit that you have. For analog circuits is better to use as much pads as you can to have a more clean supply. This can be simulated to check the circuit behavor.
For digital circuits this is not so problematic. But depends on the speed of the circuit.
The number of pads limits the final silicon area, so a compromize is necessary.
Regards bastos
|
|
| Back to top |
|
|
ASIC
Joined: 18 May 2001
Posts: 208
|
| 17 Sep 2001 22:47 |
|
|
|
bastos,
you are a real pal... Thanks a million.
ASIC
|
|
| Back to top |
|
|
cswang
Joined: 31 May 2001
Posts: 47
Helped: 1
|
| 19 Sep 2001 3:18 |
|
|
|
rule of thumb : 1mm bonding length =1nH
So you can roughly estimate what you need.
|
|
| Back to top |
|
|
peterlaaser
Joined: 14 Jan 2002
Posts: 15
|
| 09 Mar 2002 5:00 |
|
|
|
| a typical 1-mil-bondwire can take up to 500mA. The critical bottleneck is the pad itself. most standard-pads are not optimized for high currents and get electromigration-problems above 100mA. But if you stack 5 or more metallayers you can build a 500mA Supply-Pad yourself.
|
|
| Back to top |
|
|
vividsoft
Joined: 02 Jan 2002
Posts: 9
|
| 11 Mar 2002 6:11 |
|
|
|
|
|
|
| Back to top |
|
|
vividsoft
Joined: 02 Jan 2002
Posts: 9
|
| 11 Mar 2002 6:12 |
|
|
|
| Quote: |
*w*h*e*r*e*t*o*f*i*n*d*i*t
|
|
|
| Back to top |
|
|
fingers
Joined: 26 Feb 2002
Posts: 16
|
| 12 Mar 2002 1:56 |
|
|
|
Don't forget the amount of current a bond wire takes depends on its thickness.
I use 0.0005 / 0.0007 thou bond wires and i wouldn't recommend going above 200-300mA for this thickness of wire.
If current is an issue don't forget you could use gold tape, anyhting from 0.0005 to 0.002 thou can be used for greater current ability.
Also double bonds will reduce the inductance and i would recommend this if your using any kind of amplifier in the microwave frequency range.
|
|
| Back to top |
|
|
jetmarc
Joined: 17 Dec 2001
Posts: 54
|
| 11 Apr 2002 4:27 |
|
|
|
| Quote: |
I use 0.0005 / 0.0007 thou bond wires and i wouldn't recommend going above 200-300mA for this thickness of wire.
|
I want to bond at home. What equipment do I
need? I have acid to dissolve chip package
and I want to bond unused test pads to
package pins.
|
|
| Back to top |
|
|
