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Hi Robert,
I am finding your updated version of the power supply course (Learn Altium Essentials – Second Edition) very useful as I learn Altium Designer (version 19.1.6 (build 110)). I have a few questions with respect to grids in the layout. Here is an example that illustrates the issue:
The course utilizes a power supply controller (ISL6236A). It is a 32 pin QFP package with the pitch between pads of 0.5mm. You recommend that the center of that device be placed at x=25mm, and y=25mm. This causes the center of all the pads to be off of the 0.1mm grid that you recommend in either the x or the y dimension, one or the other. As an example, you can see in the image below, that the center of pad 22 is at 22.6mm x 25.75mm. The “y†dimension in this case is not on the 0.1mm grid.
When I draw a short stub from pad 22 before placing the via at the end of the stub, the end of the short stub wants to “snap†to the grid, creating a “jog†in the trace (see first image attached).
However, in your video, you did not seem to have the same problem. You apparently were able to draw a straight trace from pad 22 (see second image attached). The screen snap-shot I attached was taken from lesson 6 at 1:07:43
​Here are a couple of questions:
1. How were you able to draw the short trace without a “jog� It doesn’t look like you changed the grid, as it still shows as 0.1mm at the bottom of your screen. Maybe you turned off grid snapping?
2. I am also studying for the CID certificate and the study materials recommend that PCB layouts be done on a grid. Which PCB features are desirable to be on a grid and how does that grid relate to the 0.1mm grid that we are using as we layout the board in this course?
I am finding your updated version of the power supply course (Learn Altium Essentials – Second Edition) very useful as I learn Altium Designer (version 19.1.6 (build 110)). I have a few questions with respect to grids in the layout. Here is an example that illustrates the issue:
The course utilizes a power supply controller (ISL6236A). It is a 32 pin QFP package with the pitch between pads of 0.5mm. You recommend that the center of that device be placed at x=25mm, and y=25mm. This causes the center of all the pads to be off of the 0.1mm grid that you recommend in either the x or the y dimension, one or the other. As an example, you can see in the image below, that the center of pad 22 is at 22.6mm x 25.75mm. The “y†dimension in this case is not on the 0.1mm grid.
When I draw a short stub from pad 22 before placing the via at the end of the stub, the end of the short stub wants to “snap†to the grid, creating a “jog†in the trace (see first image attached).
However, in your video, you did not seem to have the same problem. You apparently were able to draw a straight trace from pad 22 (see second image attached). The screen snap-shot I attached was taken from lesson 6 at 1:07:43
​Here are a couple of questions:
1. How were you able to draw the short trace without a “jog� It doesn’t look like you changed the grid, as it still shows as 0.1mm at the bottom of your screen. Maybe you turned off grid snapping?
2. I am also studying for the CID certificate and the study materials recommend that PCB layouts be done on a grid. Which PCB features are desirable to be on a grid and how does that grid relate to the 0.1mm grid that we are using as we layout the board in this course?
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