Have a Complex, Off-Grid Pin Pattern to Number? Cadence Allegro16.6 IC Package Design Tools Have You Covered!

Complex dies with a mixture of digital and analog circuitry means equally complex pin patterns. Those analog areas often have pins that aren't lined up in nice, straight rows and columns. But, that doesn't mean that the pins don't still need a defined pin-numbering pattern. What do you do in this case to get the pin numbers just the way you want them? With Cadence Allegro Package Designer and SiP Layout XL tools -and their built-in symbol editing application mode--getting your numbers just the way you want them is easy as can be!

To find out more about how, with the latest 16.6 software release, you can make tweaks to your fully custom pin-numbering pattern to meet any conceivable need, just read on. In fewer than five minutes, we'll have you numbering your pins just the way you want them. You'll never fear a pin number pattern again!

Customized and Sequential Pin-Numbering Patterns

When you have pins that aren't on any kind of grid - or if you just want to have complete manual control of the number assigned to every pin - the first thing you need to do is tell the tool this. Change your application mode to the symbol-editing environment and do a quick RMB on your die (or whatever component you want to change - just watch out! You probably want your BGA to keep using its automated JEDEC standard numbering pattern!). Go into your pin-numbering settings, as you can see below, and set your labeling scheme to Customized.

Now that you've done this, the tool will no longer attempt to automatically assign pin numbers to pins of your symbol based on their location in a grid. Instead, you get complete control of the number assigned to every pin. This doesn't change any of the current pin numbers that were assigned based on any numbering scheme beforehand, however. If your pins almost follow a standard numbering pattern, this means you can probably get your numbers 95% or more correct. Either way, you can adjust one, a dozen, or all the pins in a minute.

Renumbering Pins Interactively, Individually, or Sequentially

Next up, RMB on your component again and pick the "Renumber Pins" option. This will give you a very simple interface (once again, shown below - you may need to set the "symed_renumber_pins_beta" option in your User Preferences if you haven't already):

Set the pin number you want to start with. It doesn't have to be strictly numeric, either. If you want all the pin numbers you're customizing to start with "CUSTOM" followed by a number, go ahead! Just enter "CUSTOM1" in the pin-number field. Set your increment at the same time, though in most cases, you'll probably want to leave this at its default value of 1.

You're ready to go. Take a look in the canvas. All the pins you haven't renumbered yet are shown highlighted. Click on one to assign the current pin number from the options tab to it and watch the pin-number field automatically increment. You're ready for the next pin. As you click pins and assign numbers to them, you'll notice they get dehighlighted. This makes it easy to tell which pins you have (and haven't) put into the pattern.

Oh, and that first checkbox under the increment field on the options tab? You'll want to keep that checked, too. This way, if your pattern currently has pins 1 through 100 correct, except that one pin is out of line with the others and needs to be assigned as 29, set your pin number to 29 and click it. The old pin 29 will become 30, 30 moves to 31, and so forth. Inserting pin numbers into the pattern is really that simple.

What about the worst-case scenario, though? What if you need to renumber ALL the pins of your component? You don't want to click 1000+ pins individually. So, just hold your left mouse button down and start drawing a path through the pins. As you touch each new pin, you'll see it dehighlight. When you've gone through all the pins you want to renumber on this pass, let go of your mouse button. Everything will be assigned sequential, incremented numbers based on the order you drew over them with the mouse. Can it get any easier than that?

Have an Idea for Making This Tool Even Better?

This is a powerful tool for massaging your pin numbers to get them looking exactly the way you need them. But, maybe there's something that could make the process faster still. If you have an idea to improve this - or any - command in your Allegro Package Designer or SiP Layout tool, be sure to let your Cadence customer support representative know; they'll pass your suggestions on to engineering. Come the next major release, you may just see your idea in the tool!

Jeff Gallagher