Page 148 - Make Your Own PCBs with EAGLE from Schematic Designs to Finished Boards

FIGURE 5-31 IC1 SMD package on the board layout.

You can also see that the routing is now, of course, all in a mess. This is only going to get worse,
so we may as well go back to air wires by doing a group ripup. To do this, click on the Ripup
command, then click on the Group command, drag over the whole area of the board, and right-click
and slect the option “Ripup: Group.”

We may as well set the Board Editor back to a useful state ready for layout by just showing the
layers “Top,” “Bottom,” “Pads,” “Vias,” “Unrouted,” “Dimension,” “tPlace,” and “tOrigin.” We
were kind of lucky with IC1 in that there was a drop-in SMD replacement using the same pin names.
Unfortunately, things are not quite so easy for IC2. Using the Replace tool and a search string of
“*3914V*” will find an SMD equivalent of the chip, but when we try to do the replacement, we will

get an error message Date A in the old version of device set LM3914N can’t
be mapped to any gate in the new version of this device set
(neither by name nor coordinates).
This is so because the part has been designed differently from the original and uses different

names for many of the pins. For example, the connections to the LEDs are called LED1, LED2, and so
on rather than L1, L2, and so on (Figure 5-32).