PCB Layout CAD : DRC/MRC Settings


This is a function for making teardrop shapes for connecting Lands and Routes so that the corners of the connections are not acute angles when connecting to Arc shape patterns.
In the DRC, it is checked whether there is a teardrop in specified Pads or Vias.

For more details about opening the DRC/MRC Settings screen, refer to About DRC/MRC Settings.

Example Tear Drop Settings

Teardrops will not be generated for the following objects.

Case1:Customized pads
Case2:Routes with its Cap Shape set as Square
Case3:Routes wider that pad lands
Case4:Pad lands in which teardrops do not fit

Setting Method

First, in Settings, there is an "Assignment" tab and "Advanced Settings" tab.
The "Advanced Settings" tab is used for configuring actual settings, and the "Assignment" tab is used for configuring which settings are assigned to which Net.

About the Work Procedure

STEP 1: Create a Net Class from the "Net Class" tab
STEP 2: Configure settings in the "Advanced Settings" tab
STEP 3: Assign settings to the Net Class in the "Assignment" tab

The following will explain each setting tab.

Explanation of Each Setting Tab
Tab Name Content


It is possible to assign the "Settings" that are applied to Nets set in the "Net Class".

For example, you can create a "Power Supply Net Class (GND, VCC)" Net Class, and assign the setting for "Power Supply Net Settings".
When it is not necessary to divide settings for each Net, all Nets apply to "DefaultClass",
so, assign "DefaultSetting".
* All Nets not individually assigned in the Net Class are "DefaultClass".

Advanced Settings

Configures actual settings.
Multiple definition is possible for settings.




Advanced Settings

For more details about adding settings, refer to Adding Settings.

Tear Drop Settings

Object Settings

Objects to which the teardrop shape applies are "Pads", "SMDs", and "Vias".

Item Content


Configures Tear Drop Settings for Dip Pads.


Configures Tear Drop Settings for CHIP Pads (Pads without Drills).


Configures Tear Drop Settings for Vias.


Tear Drop Settings

Configure settings for whether to apply a teardrop shape for connections between each object land and route, and settings for the shape.

Item Content

Tear Drop

It is possible to set Tear Drop as Enabled/Invalid. Tear Drop is enabled when a check is placed on the left side.


Specifies the Tear Drop shape.

Line  Arc 

* "Diameter Ratio": Specifies the Tear Drop Diameter Ratio for Pads. (Set this to 1.0 or smaller.)
   "Length Ratio": Specifies the Tear Drop Length for Pads. The distance in light blue is the ratio for the route.

The distance in orange is "Route Width × Length Ratio + Radius × Diameter Ratio". * Keep in mind that the distance differs according to the Diameter Ratio.


Configures Tear Drop Settings for Vias.


Layer Settings

For more details, refer to Layer Settings.


Assignment Settings

 For more details, refer to Assignment Settings.