Silicon ChipAltium Designer 2025 review - September 2025 SILICON CHIP
  1. Contents
  2. Publisher's Letter: Why I don’t put a space between numbers and units
  3. Feature: The Fox Report by Barry Fox
  4. Project: Compact Hi-Fi Headphone Amplifier, part one by Nicholas Vinen
  5. Feature: 0.91-inch monochrome OLED display modules by Jim Rowe
  6. Project: Two Discrete Ideal Bridge Rectifiers by Phil Prosser & Ian Ashford
  7. Feature: Max’s Cool Beans by Max the Magnificent
  8. Project: Automatic LQ Meter by Charles Kosina
  9. Back Issues
  10. Feature: Net Work by Alan Winstanley
  11. Feature: Circuit Surgery by Ian Bell
  12. Feature: Altium Designer 2025 review by Tim Blythman
  13. Project: Dual-Rail Load Protector by Stefan Keller -Tuberg
  14. Back Issues
  15. Feature: Audio Out by Max the Magnificent
  16. PartShop
  17. Market Centre
  18. Advertising Index
  19. Back Issues

This is only a preview of the September 2025 issue of Practical Electronics.

You can view 0 of the 80 pages in the full issue.

Articles in this series:
  • The Fox Report (July 2024)
  • The Fox Report (July 2024)
  • The Fox Report (September 2024)
  • The Fox Report (September 2024)
  • The Fox Report (October 2024)
  • The Fox Report (October 2024)
  • The Fox Report (November 2024)
  • The Fox Report (November 2024)
  • The Fox Report (December 2024)
  • The Fox Report (December 2024)
  • The Fox Report (January 2025)
  • The Fox Report (January 2025)
  • The Fox Report (February 2025)
  • The Fox Report (February 2025)
  • The Fox Report (March 2025)
  • The Fox Report (March 2025)
  • The Fox Report (April 2025)
  • The Fox Report (April 2025)
  • The Fox Report (May 2025)
  • The Fox Report (May 2025)
  • The Fox Report (July 2025)
  • The Fox Report (July 2025)
  • The Fox Report (August 2025)
  • The Fox Report (August 2025)
  • The Fox Report (September 2025)
  • The Fox Report (September 2025)
Items relevant to "Compact Hi-Fi Headphone Amplifier, part one":
  • Compact HiFi Headphone Amplifier PCB [01103241] (AUD $7.50)
  • Dual Horizontal PCB-mounting RCA sockets (white/red) [RCA-210] (Component, AUD $2.50)
  • Compact HiFi Headphone Amplifier kit (Component, AUD $70.00)
  • Compact HiFi Headphone Amplifier PCB pattern (PDF download) [01103241] (Free)
  • Compact HiFi Headphone Amplifier panel drilling diagram (Panel Artwork, Free)
Articles in this series:
  • Compact HiFi Headphone Amp (December 2024)
  • Compact HiFi Headphone Amp (December 2024)
  • Compact HiFi Headphone Amp (January 2025)
  • Compact HiFi Headphone Amp (January 2025)
  • Compact Hi-Fi Headphone Amplifier, part one (September 2025)
  • Compact Hi-Fi Headphone Amplifier, part one (September 2025)
Articles in this series:
  • El Cheapo Modules From Asia - Part 1 (October 2016)
  • El Cheapo Modules From Asia - Part 1 (October 2016)
  • El Cheapo Modules From Asia - Part 2 (December 2016)
  • El Cheapo Modules From Asia - Part 2 (December 2016)
  • El Cheapo Modules From Asia - Part 3 (January 2017)
  • El Cheapo Modules From Asia - Part 3 (January 2017)
  • El Cheapo Modules from Asia - Part 4 (February 2017)
  • El Cheapo Modules from Asia - Part 4 (February 2017)
  • El Cheapo Modules, Part 5: LCD module with I²C (March 2017)
  • El Cheapo Modules, Part 5: LCD module with I²C (March 2017)
  • El Cheapo Modules, Part 6: Direct Digital Synthesiser (April 2017)
  • El Cheapo Modules, Part 6: Direct Digital Synthesiser (April 2017)
  • El Cheapo Modules, Part 7: LED Matrix displays (June 2017)
  • El Cheapo Modules, Part 7: LED Matrix displays (June 2017)
  • El Cheapo Modules: Li-ion & LiPo Chargers (August 2017)
  • El Cheapo Modules: Li-ion & LiPo Chargers (August 2017)
  • El Cheapo modules Part 9: AD9850 DDS module (September 2017)
  • El Cheapo modules Part 9: AD9850 DDS module (September 2017)
  • El Cheapo Modules Part 10: GPS receivers (October 2017)
  • El Cheapo Modules Part 10: GPS receivers (October 2017)
  • El Cheapo Modules 11: Pressure/Temperature Sensors (December 2017)
  • El Cheapo Modules 11: Pressure/Temperature Sensors (December 2017)
  • El Cheapo Modules 12: 2.4GHz Wireless Data Modules (January 2018)
  • El Cheapo Modules 12: 2.4GHz Wireless Data Modules (January 2018)
  • El Cheapo Modules 13: sensing motion and moisture (February 2018)
  • El Cheapo Modules 13: sensing motion and moisture (February 2018)
  • El Cheapo Modules 14: Logarithmic RF Detector (March 2018)
  • El Cheapo Modules 14: Logarithmic RF Detector (March 2018)
  • El Cheapo Modules 16: 35-4400MHz frequency generator (May 2018)
  • El Cheapo Modules 16: 35-4400MHz frequency generator (May 2018)
  • El Cheapo Modules 17: 4GHz digital attenuator (June 2018)
  • El Cheapo Modules 17: 4GHz digital attenuator (June 2018)
  • El Cheapo: 500MHz frequency counter and preamp (July 2018)
  • El Cheapo: 500MHz frequency counter and preamp (July 2018)
  • El Cheapo modules Part 19 – Arduino NFC Shield (September 2018)
  • El Cheapo modules Part 19 – Arduino NFC Shield (September 2018)
  • El cheapo modules, part 20: two tiny compass modules (November 2018)
  • El cheapo modules, part 20: two tiny compass modules (November 2018)
  • El cheapo modules, part 21: stamp-sized audio player (December 2018)
  • El cheapo modules, part 21: stamp-sized audio player (December 2018)
  • El Cheapo Modules 22: Stepper Motor Drivers (February 2019)
  • El Cheapo Modules 22: Stepper Motor Drivers (February 2019)
  • El Cheapo Modules 23: Galvanic Skin Response (March 2019)
  • El Cheapo Modules 23: Galvanic Skin Response (March 2019)
  • El Cheapo Modules: Class D amplifier modules (May 2019)
  • El Cheapo Modules: Class D amplifier modules (May 2019)
  • El Cheapo Modules: Long Range (LoRa) Transceivers (June 2019)
  • El Cheapo Modules: Long Range (LoRa) Transceivers (June 2019)
  • El Cheapo Modules: AD584 Precision Voltage References (July 2019)
  • El Cheapo Modules: AD584 Precision Voltage References (July 2019)
  • Three I-O Expanders to give you more control! (November 2019)
  • Three I-O Expanders to give you more control! (November 2019)
  • El Cheapo modules: “Intelligent” 8x8 RGB LED Matrix (January 2020)
  • El Cheapo modules: “Intelligent” 8x8 RGB LED Matrix (January 2020)
  • El Cheapo modules: 8-channel USB Logic Analyser (February 2020)
  • El Cheapo modules: 8-channel USB Logic Analyser (February 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules (May 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules (May 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules, Part 2 (June 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules, Part 2 (June 2020)
  • El Cheapo Modules: Mini Digital Volt/Amp Panel Meters (December 2020)
  • El Cheapo Modules: Mini Digital Volt/Amp Panel Meters (December 2020)
  • El Cheapo Modules: Mini Digital AC Panel Meters (January 2021)
  • El Cheapo Modules: Mini Digital AC Panel Meters (January 2021)
  • El Cheapo Modules: LCR-T4 Digital Multi-Tester (February 2021)
  • El Cheapo Modules: LCR-T4 Digital Multi-Tester (February 2021)
  • El Cheapo Modules: USB-PD chargers (July 2021)
  • El Cheapo Modules: USB-PD chargers (July 2021)
  • El Cheapo Modules: USB-PD Triggers (August 2021)
  • El Cheapo Modules: USB-PD Triggers (August 2021)
  • El Cheapo Modules: 3.8GHz Digital Attenuator (October 2021)
  • El Cheapo Modules: 3.8GHz Digital Attenuator (October 2021)
  • El Cheapo Modules: 6GHz Digital Attenuator (November 2021)
  • El Cheapo Modules: 6GHz Digital Attenuator (November 2021)
  • El Cheapo Modules: 35MHz-4.4GHz Signal Generator (December 2021)
  • El Cheapo Modules: 35MHz-4.4GHz Signal Generator (December 2021)
  • El Cheapo Modules: LTDZ Spectrum Analyser (January 2022)
  • El Cheapo Modules: LTDZ Spectrum Analyser (January 2022)
  • Low-noise HF-UHF Amplifiers (February 2022)
  • Low-noise HF-UHF Amplifiers (February 2022)
  • A Gesture Recognition Module (March 2022)
  • A Gesture Recognition Module (March 2022)
  • Air Quality Sensors (May 2022)
  • Air Quality Sensors (May 2022)
  • MOS Air Quality Sensors (June 2022)
  • MOS Air Quality Sensors (June 2022)
  • PAS CO2 Air Quality Sensor (July 2022)
  • PAS CO2 Air Quality Sensor (July 2022)
  • Particulate Matter (PM) Sensors (November 2022)
  • Particulate Matter (PM) Sensors (November 2022)
  • Heart Rate Sensor Module (February 2023)
  • Heart Rate Sensor Module (February 2023)
  • UVM-30A UV Light Sensor (May 2023)
  • UVM-30A UV Light Sensor (May 2023)
  • VL6180X Rangefinding Module (July 2023)
  • VL6180X Rangefinding Module (July 2023)
  • pH Meter Module (September 2023)
  • pH Meter Module (September 2023)
  • 1.3in Monochrome OLED Display (October 2023)
  • 1.3in Monochrome OLED Display (October 2023)
  • 16-bit precision 4-input ADC (November 2023)
  • 16-bit precision 4-input ADC (November 2023)
  • 1-24V USB Power Supply (October 2024)
  • 1-24V USB Power Supply (October 2024)
  • 14-segment, 4-digit LED Display Modules (November 2024)
  • 0.91-inch OLED Screen (November 2024)
  • 14-segment, 4-digit LED Display Modules (November 2024)
  • 0.91-inch OLED Screen (November 2024)
  • The Quason VL6180X laser rangefinder module (January 2025)
  • The Quason VL6180X laser rangefinder module (January 2025)
  • TCS230 Colour Sensor (January 2025)
  • TCS230 Colour Sensor (January 2025)
  • Using Electronic Modules: 1-24V Adjustable USB Power Supply (February 2025)
  • Using Electronic Modules: 1-24V Adjustable USB Power Supply (February 2025)
  • Low-cost electronic modules: 8×16 LED Matrix module (July 2025)
  • Low-cost electronic modules: 8×16 LED Matrix module (July 2025)
  • Modules: Thin-Film Pressure Sensor (August 2025)
  • Modules: Thin-Film Pressure Sensor (August 2025)
  • 0.91-inch monochrome OLED display modules (September 2025)
  • 0.91-inch monochrome OLED display modules (September 2025)
Articles in this series:
  • Max’s Cool Beans (January 2025)
  • Max’s Cool Beans (January 2025)
  • Max’s Cool Beans (February 2025)
  • Max’s Cool Beans (February 2025)
  • Max’s Cool Beans (March 2025)
  • Max’s Cool Beans (March 2025)
  • Max’s Cool Beans (April 2025)
  • Max’s Cool Beans (April 2025)
  • Max’s Cool Beans (May 2025)
  • Max’s Cool Beans (May 2025)
  • Max’s Cool Beans (June 2025)
  • Max’s Cool Beans (June 2025)
  • Max’s Cool Beans (July 2025)
  • Max’s Cool Beans (July 2025)
  • Max’s Cool Beans (August 2025)
  • Max’s Cool Beans (August 2025)
  • Max’s Cool Beans (September 2025)
  • Max’s Cool Beans (September 2025)
Articles in this series:
  • Win a Microchip Explorer 8 Development Kit (April 2024)
  • Win a Microchip Explorer 8 Development Kit (April 2024)
  • Net Work (May 2024)
  • Net Work (May 2024)
  • Net Work (June 2024)
  • Net Work (June 2024)
  • Net Work (July 2024)
  • Net Work (July 2024)
  • Net Work (August 2024)
  • Net Work (August 2024)
  • Net Work (September 2024)
  • Net Work (September 2024)
  • Net Work (October 2024)
  • Net Work (October 2024)
  • Net Work (November 2024)
  • Net Work (November 2024)
  • Net Work (December 2024)
  • Net Work (December 2024)
  • Net Work (January 2025)
  • Net Work (January 2025)
  • Net Work (February 2025)
  • Net Work (February 2025)
  • Net Work (March 2025)
  • Net Work (March 2025)
  • Net Work (April 2025)
  • Net Work (April 2025)
  • Net Work (September 2025)
  • Net Work (September 2025)
Articles in this series:
  • Circuit Surgery (April 2024)
  • STEWART OF READING (April 2024)
  • Circuit Surgery (April 2024)
  • STEWART OF READING (April 2024)
  • Circuit Surgery (May 2024)
  • Circuit Surgery (May 2024)
  • Circuit Surgery (June 2024)
  • Circuit Surgery (June 2024)
  • Circuit Surgery (July 2024)
  • Circuit Surgery (July 2024)
  • Circuit Surgery (August 2024)
  • Circuit Surgery (August 2024)
  • Circuit Surgery (September 2024)
  • Circuit Surgery (September 2024)
  • Circuit Surgery (October 2024)
  • Circuit Surgery (October 2024)
  • Circuit Surgery (November 2024)
  • Circuit Surgery (November 2024)
  • Circuit Surgery (December 2024)
  • Circuit Surgery (December 2024)
  • Circuit Surgery (January 2025)
  • Circuit Surgery (January 2025)
  • Circuit Surgery (February 2025)
  • Circuit Surgery (February 2025)
  • Circuit Surgery (March 2025)
  • Circuit Surgery (March 2025)
  • Circuit Surgery (April 2025)
  • Circuit Surgery (April 2025)
  • Circuit Surgery (May 2025)
  • Circuit Surgery (May 2025)
  • Circuit Surgery (June 2025)
  • Circuit Surgery (June 2025)
  • Circuit Surgery (July 2025)
  • Circuit Surgery (July 2025)
  • Circuit Surgery (August 2025)
  • Circuit Surgery (August 2025)
  • Circuit Surgery (September 2025)
  • Circuit Surgery (September 2025)
Articles in this series:
  • Techno Talk (February 2020)
  • Techno Talk (February 2020)
  • Techno Talk (March 2020)
  • Techno Talk (March 2020)
  • (April 2020)
  • (April 2020)
  • Techno Talk (May 2020)
  • Techno Talk (May 2020)
  • Techno Talk (June 2020)
  • Techno Talk (June 2020)
  • Techno Talk (July 2020)
  • Techno Talk (July 2020)
  • Techno Talk (August 2020)
  • Techno Talk (August 2020)
  • Techno Talk (September 2020)
  • Techno Talk (September 2020)
  • Techno Talk (October 2020)
  • Techno Talk (October 2020)
  • (November 2020)
  • (November 2020)
  • Techno Talk (December 2020)
  • Techno Talk (December 2020)
  • Techno Talk (January 2021)
  • Techno Talk (January 2021)
  • Techno Talk (February 2021)
  • Techno Talk (February 2021)
  • Techno Talk (March 2021)
  • Techno Talk (March 2021)
  • Techno Talk (April 2021)
  • Techno Talk (April 2021)
  • Techno Talk (May 2021)
  • Techno Talk (May 2021)
  • Techno Talk (June 2021)
  • Techno Talk (June 2021)
  • Techno Talk (July 2021)
  • Techno Talk (July 2021)
  • Techno Talk (August 2021)
  • Techno Talk (August 2021)
  • Techno Talk (September 2021)
  • Techno Talk (September 2021)
  • Techno Talk (October 2021)
  • Techno Talk (October 2021)
  • Techno Talk (November 2021)
  • Techno Talk (November 2021)
  • Techno Talk (December 2021)
  • Techno Talk (December 2021)
  • Communing with nature (January 2022)
  • Communing with nature (January 2022)
  • Should we be worried? (February 2022)
  • Should we be worried? (February 2022)
  • How resilient is your lifeline? (March 2022)
  • How resilient is your lifeline? (March 2022)
  • Go eco, get ethical! (April 2022)
  • Go eco, get ethical! (April 2022)
  • From nano to bio (May 2022)
  • From nano to bio (May 2022)
  • Positivity follows the gloom (June 2022)
  • Positivity follows the gloom (June 2022)
  • Mixed menu (July 2022)
  • Mixed menu (July 2022)
  • Time for a total rethink? (August 2022)
  • Time for a total rethink? (August 2022)
  • What’s in a name? (September 2022)
  • What’s in a name? (September 2022)
  • Forget leaves on the line! (October 2022)
  • Forget leaves on the line! (October 2022)
  • Giant Boost for Batteries (December 2022)
  • Giant Boost for Batteries (December 2022)
  • Raudive Voices Revisited (January 2023)
  • Raudive Voices Revisited (January 2023)
  • A thousand words (February 2023)
  • A thousand words (February 2023)
  • It’s handover time (March 2023)
  • It’s handover time (March 2023)
  • AI, Robots, Horticulture and Agriculture (April 2023)
  • AI, Robots, Horticulture and Agriculture (April 2023)
  • Prophecy can be perplexing (May 2023)
  • Prophecy can be perplexing (May 2023)
  • Technology comes in different shapes and sizes (June 2023)
  • Technology comes in different shapes and sizes (June 2023)
  • AI and robots – what could possibly go wrong? (July 2023)
  • AI and robots – what could possibly go wrong? (July 2023)
  • How long until we’re all out of work? (August 2023)
  • How long until we’re all out of work? (August 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • Holy Spheres, Batman! (October 2023)
  • Holy Spheres, Batman! (October 2023)
  • Where’s my pneumatic car? (November 2023)
  • Where’s my pneumatic car? (November 2023)
  • Good grief! (December 2023)
  • Good grief! (December 2023)
  • Cheeky chiplets (January 2024)
  • Cheeky chiplets (January 2024)
  • Cheeky chiplets (February 2024)
  • Cheeky chiplets (February 2024)
  • The Wibbly-Wobbly World of Quantum (March 2024)
  • The Wibbly-Wobbly World of Quantum (March 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - Program that! (June 2024)
  • Techno Talk - Program that! (June 2024)
  • Techno Talk (July 2024)
  • Techno Talk (July 2024)
  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - I don’t want to be a Norbert... (September 2024)
  • Techno Talk - I don’t want to be a Norbert... (September 2024)
  • Techno Talk - Sticking the landing (October 2024)
  • Techno Talk - Sticking the landing (October 2024)
  • Techno Talk (November 2024)
  • Techno Talk (November 2024)
  • Techno Talk (December 2024)
  • Techno Talk (December 2024)
  • Techno Talk (January 2025)
  • Techno Talk (January 2025)
  • Techno Talk (February 2025)
  • Techno Talk (February 2025)
  • Techno Talk (March 2025)
  • Techno Talk (March 2025)
  • Techno Talk (April 2025)
  • Techno Talk (April 2025)
  • Techno Talk (May 2025)
  • Techno Talk (May 2025)
  • Techno Talk (June 2025)
  • Techno Talk (June 2025)
  • Techno Talk (July 2025)
  • Techno Talk (July 2025)
  • Techno Talk (August 2025)
  • Techno Talk (August 2025)
  • Audio Out (September 2025)
  • Audio Out (September 2025)
EDA Software Review Altium Designer 25 Review by Tim Blythman Altium Designer 25 is the latest version of the EDA (electronics design automation) software that we use for all of our PCB designs. This new version was released late in 2024, and we have spent some time putting it through its paces. Here is what we have found. A ltium Designer may not be the cheapest PCB design package, but it certainly is very capable and becoming quite mature. It has been around for over 30 years now; it can trace its history back to a software package called Protel Autotrax. Like many software packages, Altium Designer gets frequent updates, including annual major revisions that often introduce new features. I have been using Altium Designer for around ten years now, so I was interested to see what was new compared to the previous major version from 2024, Altium Designer 24. As this is a complex piece of software, I will be concentrating mainly on the change and additions, rather than its core functions like schematic capture, PCB design and simulation. Renesas Electronics acquired Altium in August 2024. Renesas is a Japanese semiconductor manufacturer that includes the semiconductor operations of Hitachi, Mitsubishi and NEC. That marks an interesting geographical history for Altium, with Protel Systems Pty Ltd originally founded as an Australian company. For many years, it has been headquartered in San Diego, California. We’re most familiar with Renesas Electronics as the manufacturer of the RA4M1 microprocessor used in the new Arduino Uno R4 microcontroller board. The Raspberry Pi 5 also uses a Renesas power management IC. AD25 overview Altium Designer 25 looks and feels much the same as previous versions, 56 but like many modern applications, it is constantly evolving. This time we are looking at version 25.0.2. The webpage at www.altium.com/ documentation/altium-designer/new lists details of the various version updates and the versions (and subversions) to which they apply. So you can easily see which version has a particular feature. Some features that are present are disabled by default but can be turned on via the Advanced Settings window of Preferences. Others are available as Extensions, which can be installed from the Extensions and Updates window. Such features may still be at the beta testing stage. Beta testing means that the feature is essentially complete but not fully tested. It is a good way to get early access to novel features, and there is usually the ability to toggle these features on and off. Just as with previous versions, it is possible to install multiple versions of Altium Designer alongside each other. You might like to do this to try out the features in a new version without committing to it until you are happy with the changes. Amongst other videos, the new features are also presented at the Altium Academy YouTube channel (www.youtube.com/<at>AltiumAcademy). These and other training materials are also available on the Home Page of the Altium Designer application. Performance Altium Designer 25 claims to have much improved performance, especially with large designs. Our designs are typically on the smaller and less complex side, so we’re not really able to put this aspect to the test. But we were certainly happy with its responsiveness in the time we’ve been using it. This applies to many aspects of Altium Designer, including the schematic and PCB editors, and Draftsman, as well as in collaborative tools like Altium 365 and PCB CoDesign. Operations like opening documents, repouring polygons, placing stitching vias and bulk copying and pasting have all been sped up. These improvements have been brought about through better memory management and caching of data where possible. On a related note, recent versions of Altium Designer (starting with 24.8) use the newer .NET 6 software framework. Previously, Altium Designer used Microsoft’s proprietary and now obsolete .NET Framework 4.8. Unsurprisingly, .NET 6 is also faster. Interestingly, .NET 6 is fully opensource. It is intended to be modular and works across multiple platforms (including Windows, Linux and macOS). Dare we wonder if this is the first step of being able to run Altium Designer on a Linux PC or Mac? The SI Analyzer by Keysight Another extension that sounds quite handy is the Signal Integrity Analyzer by Keysight, although this is another one that we probably won’t ever need to use due to our modest designs. As the name suggests, it is intended to Practical Electronics | September | 2025 Altium Designer 25 Fig.1: the Signal Integrity Analyzer by Keysight can be used post-layout to validate signal integrity and provide checks on parameters such as impedance, delay, insertion loss and return loss. This will be very handy to validate high-speed designs before committing to PCB manufacture. Source: www.altium.com/documentation/altiumdesigner/new?version=24#sianalyzer-by-keysight-openbeta-24-10 Fig.2 (below): this trace is ‘necked down’ to fit through a narrow gap between other pads; we did this manually, using an older version of Altium Designer. The new auto-shrink feature allows this to be done automatically during interactive routing. perform signal integrity analysis on high-speed designs. Fig.1 shows the phases of such an analysis. It can calculate things such as impedance, delay, insertion loss and return loss based on the PCB layout. This can help to validate the PCB before it is committed to manufacture. Signal Integrity Analyzer is currently a beta feature and requires the SI Analyzer by Keysight extension to be installed; there is a free 14-day trial available for this feature. Routing When routing the traces on a board, it is sometimes necessary to use a track narrower than the preferred width to fit through a congested or tight area. This is often described as ‘necking down’, where the trace is narrowed down to a thin neck just long enough and narrow enough to fit. Previously, you would have to do this manually, but there is now an option to auto-shrink the width to the minimum you’ve set. This will be handy, since manually creating a neck can be a fiddly process, especially if you want the result to be Practical Electronics | September | 2025 neat. In addition, a new design rule allows the neck to have a maximum specified length, to avoid having too much resistance or increased fragility. Currently, both these features are in beta and need to be activated in Advanced Settings. The auto-shrink feature is enabled with the “PCB.Routing. EnableAutoShrinking” option, while the neck-down rule follows the “PCB. Rules.RoutingNeckdown” setting. There is also an option to centre traces when routing. Typically, the auto-router will place traces at the minimum allowed clearance from the nearest track, but spreading the traces out may be preferred. It can also make the routing neater, since the traces will be spread out more evenly. This is also a beta feature and is set with the “PCB.EnableTraceCentering” advanced setting. Fig.2 shows an example of a trace necking down through a narrow gap on our Thermal Controller PCB, used in a project published in the March & April 2021 issues. Single-layer PCBs For simple designs, a single-layer PCB (with copper on just one side) can be an economical choice, especially for designs on flexible substrates. Large production runs can warrant the savings in eliminating a copper layer where that is feasible. It’s now possible to lay out single-­ layer PCBs by enabling the “PCB. SingleLayerStack.Support” option in Advanced Settings, then removing a copper layer from a two-layer PCB stack. Constraint Manager The Constraint Manager unifies design constraints from both the schematic and PCB layout. It works in place of the PCB Rule and Constraints Editor dialog (Design Rules). A project can be set up (at creation) to use the Constraint Manager or to use the older Design Rules. There is also a tool that can convert a project from using Design Rules into one that is compatible with the Constraint Manager. It provides a hierarchical system that is automatically translated into the priority in which rules are applied. Constraint Manager can be enabled by 57 EDA Software Review Source: www.altium.com/ documentation/altium-designer/ constraint-manager Fig.3: the Constraint Manager provides a new interface for managing design constraints (design rules) across a project. Older projects can be upgraded to use the Constraint Manager. setting the “System.ConstraintManager” option in Advanced Settings. Fig.3 shows some views of the Constraint Manager. Importing Occasionally, we have to deal with contributed PCBs that have been designed using a different EDA tool, and sometimes we need to change them. This might be as simple as making a small change to the silkscreen markings or could involve a major revision of the copper routing layers. Some changes can be made by directly editing the Gerber files, but having access to fully editable PCB design files is better for many reasons. Firstly, that makes it possible to run design rule checks to validate that any changes do not cause a manufacturing issue like shorted traces. It then becomes possible to make further revisions if needed in the future. Whatever the reason, this means that we need the ability to import designs from other EDA tools into Altium Designer so that they can be turned into native Altium Designer files, such as SchDoc schematic files or PcbDoc PCB files. 58 The latest version of the importer now works with KiCad designs from KiCad version 7 or 8. This is available as an extension known as the KiCad Importer Extension and can be found in Extensions and Updates. Their website at https://pemag.au/ link/ac41 has more information on importing designs from other tools. Fig.4 shows a screenshot from our installation of the Software Extensions that are on offer. We have also previously used the free online Altium 365 Viewer, which is at www.altium.com/viewer This now supports KiCad files, and we had no trouble using it to view some KiCad PCB files that we found online. Wire bonding Altium Designer can be used for designing much more than just traditional planar substrate PCBs. We were already aware of Altium Designer’s ability to work with flexible and hybrid (rigid-flex) PCBs, printed electronics and 3D-printed substrates using the 3D-MID (three-dimensional mechatronic integrated device) process. Another example is the recent Harness Designer. One of the technologies supported by Altium Designer 25 is COB (chipon-board) using wire bonding. COB involves bare silicon chip dies being bonded directly to a PCB. Connections are made from pads on the die (die pads) to the bond finger pads on the PCB by means of bond wires. The bond wires used in COB applications are much the same as the bond wires used to connect a silicon chip to its leadframe in a traditionally packaged integrated circuit. These are very fine wires of a metal such as gold, copper or aluminium that are welded to their pads using heat, pressure or ultrasonic energy. The process is typically performed by an automated robotic system. You can see some images of a COB design at www.altium.com/documentation/ altium-designer/wire-bonding while the photos at upper right shows two examples of silicon dice bonded to a PCB. Creating a COB design involves adding a Die layer and a Bond wire layer to a PCB document or library. A complete footprint ‘package’ including die pads, bond finger pads, and bond wires can be created, in which case the Practical Electronics | September | 2025 Altium Designer 25 Fig.4: numerous Altium Designer extensions can be installed from the Extensions and Updates tab. This shows just some of the extensions available on our system. bond finger pads can be simply routed to on the copper layers. Alternatively, a die with die pads can be placed alongside separate bond finger pads. The bond wires are then placed manually. With the current version, wire bonding can be enabled with the “PCB.Wirebonding” option in the Advanced Settings dialog. For manufacture, a wire bonding table report can be generated. As you can see from Fig.5, Altium Designer’s 3D rendering allows you to see all aspects of a wire-bonded design. For example, you can visually check that crossed bond wires pass at different heights to avoid collisions. We find the 3D views invalu- able for making sanity checks on our PCB layouts. Licensing There are three different subscription levels available for Altium Designer: Standard, Pro and Enterprise. They differ in the number of features that are included and more information is available at www.altium.com/ altium-designer/licensing Resources Altium offers numerous resources to allow users to make the best use of Altium Designer. You can view a recent webinar (recorded in November) at https://pemag.au/link/ac42 Fig.5: Altium Designer 25 now allows wire bonding between silicon dies and PCBs. This image shows an example of two COB (chip on board) dies bonded to the PCB below. Source: www.altium. com/documentation/ altium-designer/wirebonding#placing-wirebonds-in-a-pcb Practical Electronics | September | 2025 Two examples of chips bonded directly to PCB pads. Source: www.rocket-pcb.com/rocket-pcbwholesale-wire-bonding-technologybulk-fabrication-for-electronics In addition to covering the important aspects of a feature (in this case, Single-­layer PCBs), it follows with a live demonstration of how to use that feature within Altium Designer. Altium also has a free trial offer for new users. It allows you to use a fully featured trial version of Altium Designer for 15 days; see www.altium. com/altium-designer/free-trial Conclusion Altium continues to make incremental updates to Altium Designer. While there are some bigger features that we would struggle to use fully, such as wire bonding, they are no doubt useful for larger organisations. It is good to see that they continue to improve usability and work on basic features such as routing. We hope that the switch to the .NET 6 framework is the beginning of crossplatform support. We’re especially keen to be able to use Altium Designer on Linux, since so many of the other programs that we use already allow that. For more information on Altium Designer, visit www.altium.com/ altium-designer PE 59