On Jan 29, 2008 4:25 AM, Richard Rasker <[EMAIL PROTECTED]> wrote: > Usually, I try looking up a symbol with a similar layout, but I got a > bit confused here. For example, there are two different CMOS 4053 > symbols. The 4053-1.sym features separate dual-channel switches, > selectable by defining the slot. But how do I connect the Enable and VEE > pins (#6 and 7, respectively) to an arbitrary other component? And how > to connect the power pins? When I look into the .sym file, I see that > VDD, VSS and VEE have been defined as nets (with Enable tied to VSS -- > which is not good). Does this mean that all VEE pins from multiple > 4053's are automatically tied together?
It sounds like there is a mistake in 4053-1.sym. Nets that are named the same get connected. What I do for power pins is use a separate power symbol. Just make sure that both symbols have the the same refdes. For digital symbols I usually have a separate page (or section) for power symbols and the corresponding local decoupling caps. I have a script that takes symbols with embedded power nets and creates a series of power symbols and non-power symbols. The script is called create-np-symbols and is at http://www.luciani.org/geda/util/util-index.html > How do I define this device as four slotted opamp elements with > dedicated standby and phantom ground pins? Or would I better create one > big, 16-pin symbol incorporating everything? You could make a four slotted op-amp symbol and a separate power/ground/standby symbol. When you place the symbols in your schematic just keep the refdeses the same. Depending on the amount of peripheral circuitry a 16-pin symbol could also work. If there is a lot of peripheral circuitry around each op-amp then I would do the two symbol approach. (* jcl *) -- http://www.luciani.org _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user