UltraCAD Design, Inc

22518 SE 45th Lane
Issaquah, WA  98029


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UltraCAD Design, Inc.'s Homepage

What is UltraCAD? UltraCAD Design, Inc was a printed circuit board design service bureau located in the great Pacific Northwest. We specialized in large, complex, fast turn designs common in the video processing and data processing industries. Our customers came from all over the United States --- California to New Hampshire --- with over 95% of our business from repeat, satisfied customers. See special note below about our new relationship with Monsoon Solutions, Inc.

        * NEWS *

Error We have discovered an error in our popular UCADPCB calculator for calculating the trace current/temperature relationships for 3 Oz. Internal traces. This error has been corrected in our UCADPCB calculator (v4.3) and in the Errata page for our PCB Trace and Via..... book, here. Version 4.3 of our UCADPCB calculator is a free upgrade for anyone holding a license from version 3.0 on. The error does not impact our latest calculator, UCAD_TTemp.


New Booklet

This new booklet provides detailed PCB trace current/temperature charts covering 7 trace thicknesses and 11 trace widths: 1/4, 1/2, 1.0, 2.0, 3.0, 4.0, and 5.0 Oz trace thicknesses and 15, 25, 50, 80, 100, 150, 200, 250, 300, 400, and 500 mil trace widths.


Guidelines are provided to help estimate an internal trace temperature based on what the external temperature is/would be and the relative depth of the trace.


The text summarizes the factors that influence trace heating (i2R) and trace cooling (thermal conductivity through the dielectric, convection, and radiation.)


Learn more about it here.

New Trace Calculator



  UltraCAD’s newest Current/Temperature calculator will solve for any thickness and any width over a  very wide range. It is based on the charts in our new Trace Current/Temperature booklet and subsequent thermal modeling. It will also solve for internal trace temperatures at any depth into the board (not just the midpoint.)


Learn more about it here:


  SPECIAL OFFER: Receive a FREE PDF** copy of the new Trace Current/Temperature booklet with a purchase of a UCAD_TTemp calculator license.
Latest Book
2nd. Edition


Newly released! 2nd Edition.

Finally! For the first time, here is a complete, thorough analysis of the relationships between PCB trace (and via) currents and trace temperatures. All in one place! The book covers all the research Brooks and Dr. Johannes Adam (Leimen, Germany) performed over a two-year period.

Doug published this 2nd Edition in 2017, To learn more about it, go here.

SPECIAL LIMITED TIME OFFER: Purchase a new license for UltraCAD's PCB4 calculator and receive a FREE PDF** copy of this new edition. Go here for more information

To see all of Doug's books, go here:

New LiveLesson Videos   Douglas Brooks and Prentice Hall have combined to make available Doug's signal integrity seminars to all designers and engineers in the comfort of their homes and/or offices. These videos, encompassing nine lesson titles and over 7 hours of videos, cover all of the topics Doug's seminars have become famous for. Go here to learn more about these lessons. 
New Book Our Doug Brooks' new book came out in 2013. It is titled "PCB Currents; How They Flow, How They React." Go here to learn more about it.

Trace Calculator
v. 4.3


UltraCAD's popular UCADPCB Trace Calculator has been updated to Version 4.3 to incorporate the new findings by Brooks and Dr. Adam. The "fit" to the ICP 2152 curves is now very tight, and the fusing section takes advantage of the fusing thermal simulation results Brooks and Adam obtained. The calculator still has the benefits of incorporating the skin effect, and allows calculations for resistance below zero degrees C. (4.3 upgrade effective mid 2015)

This is a free upgrade for holders of previous 3.x, 4.x, or Universal licenses. Learn more about it here.



Impedance Calculator Upgrade

UltraCAD's popular UCCALC trace impedance calculator has been upgraded to version 3.5. This is a free upgrade for holders of previous licenses. The upgrade expands the input options for the variables so that it can now be used for significantly smaller traces than before. Learn more about it here.

       * FEATURES *
Articles &

Our president, Doug Brooks, has written several articles and a series of columns for Printed Circuit Design magazine. He has also begun a series of web-based articles for Mentor Graphics.  For a list of the all Brooks' papers and articles, click here.
Books Doug Brooks' 2003 book (published by Prentice Hall) is available through bookstores. Click here to learn more about it, for ordering information, and to find a Table of Contents. Don't miss this great resource. (ISBN 0-13-141884-X)

Click here to go to the book's Resource Page

Doug's book Has been translated into Chinese and is now available in Asia.

& Tools
UltraCAD Has developed several freeware calculators (and now four for-license calculators) for PCB designers. Calculator topics include transmission line impedance, crosstalk, relationships between trace current and temperature, and relating trace geometries (width and thickness) to equivalent wire gauge. A fifth calculator helps analyze the combined effects of bypass capacitor capacitance, inductance (and therefore self-resonant frequency) and ESR. A newer calculator does differential impedance and replaces our original calculator, introduced many years ago, that has gained acceptance around the world. Our latest version of out UCADPCB4 calculator adds the Skin Effect to complex PCB calculations. And out newest calculator will solve for trace current/temperature parameters for any trace thickness and width. Check our our calculator page here.
Simulations Check out our simulations that we are now making available to the public
Humor Sometimes our imagination runs away from us (or maybe there are periods when we simply don't have enough to do.) UltraCAD has contributed several humorous articles to Printed Circuit Design's "Back Page" through the years, including the classic "Flying Electrons." Others included such things as smart electrons and why service bureaus should be paid by the government for NOT designing boards. Read all about them here.
Personnel Look here for résumé's of UltraCAD's personnel.
Guestbook Please sign our guestbook.
       * Philosophies *
Partnering Our statement on partnering has gathered a long list people who have endorsed it and embodied as their own philosophy, also. Check it out here.
Price We have some opinions about the difference between lowest bid and lowest COST. They are reprinted here.
* Announcement *
UltraCAD and Monsoon Solutions, Inc. UltraCAD has reached an agreement with Monsoon Solutions, Inc. (also of Bellevue, WA) whereby Monsoon will do all board design work for UltraCAD. Dave Graves has moved his offices over to Monsoon. Dave and Monsoon can be reached here. Doug Brooks will continue to be responsible for the rest of UltraCAD's business activities.