Tuesday, November 26, 2013

How to use Schematic CAD Drawings for Cable Assemblies: Part 1

Most electronic engineers work on products that require Printed Circuit Board designs to be interconnected by cable assemblies. As you might have already noticed, some dedicated tools that primarily focus on designing cable assemblies, while powerful, are quite expensive and beyond the scope of just creating a simple cable design. Most of the industries they are focusing on are automotive, HVAC, and aerospace firms. So you inquire yourself, what is the best alternative? The answer is simply in front of you, utilize your ECAD tool to create the cable assembly!

When working in Altium Designer, I acknowledge all I can do within the tool; I can create my schematic layouts and PCB layouts, I can manage libraries in many ways, and I can control document sources through Version Control. But there are often other questions that come to mind:

  • What if I wanted to create a design that will determine what the connections are going to be like through a cable?
  • How can I trace where signals are going, through a designed cable, in an automated way - and how can the design software help?
  • How can I quickly and effectively generate a detailed cable assembly drawing for the shop floor?

The answer is, use the Altium Designer schematic editor! You can generate very detailed cable drawings with the assistance of importing DXF/DWG files. For example, you can import mechanical drawings of connector heads or crimps that are will be needed for assembly. This way, the assembler can have the life-like drawing to refer to while building the cable. Below is a sample of such a cable drawing:

Figure 1. Example Cable Assembly Drawing.

As an example here (see Figure 1), we have a scaled length mechanical cable drawing, with two 1:1 sized connectors, one at each end. Below the mechanical drawing is the schematic representation of it using schematic symbols for the connectors, joined with wires. Within this schematic symbol diagram, you can see that net labels are linked to each connection. The bubbles with arrows (leader notes) represent a line item that you can refer to within the Bill of Materials. Once you have written your assembly notes, you can then send the ready drawing to the assembly house that makes your cables.

Through my own real-world experience, and in collaboration with other work friends, we came up with a robust and powerful methodology for cable design in Altium Designer schematics that takes care of these needs. So, throughout this blog series, I want to share with you:

  • How to generate the library parts as the building blocks of the cable assembly.
  • How to use the library parts to generate a complete and well drawn cable assembly.
  • How to prep and finalize the cable drawing to create your labels and generate outputs to hand-off to the manufacturer.

The first step is how can I get my parts placed as shown in the diagram? The simple answer is to create a multi-part library. What the library will encompass is the cables, connector heads, crimps, and any other mechanical drawing along with the schematic symbol. This will be further discussed in my next installment (part 2) of the Cable Assembly Blog Series.


Thursday, November 7, 2013

Announcement: New Libraries for AMS, ISSI SRAM & STM32

New Libraries

The Altium Content Team is pleased to announce the release of several new board-level libraries for vendors including AMS, ISSI and STMicroelectronics. From AMS it’s a mixed selection of parts covering the lion’s share of their catalog, ISSI is all about SRAM, and we’ve finally updated the STM32 families including the addition of STM32 F3.

We’ve also just shared our first batch of components developed directly as customer requests! These cover several different manufacturer parts and were created in response to feedback received via the content request form. This is the first of 3 releases that should see us deliver 99% of the individual components that have been requested so far.

More than 10,000 new components have been released! Here’s the breakdown of what’s included:

Audio (40) Data Converters (76) Interfaces (28) Light Sensors (112)

Lighting Management (91) Magnetic Position Sensors (45) Piezo Motor Drivers (3)

Power Converters (1) Power Management (260) RF Products (18)

STM32 F3 (37) STM32 F4 (135) STM32 F0 (53) STM32 F1 (244)

STM32 F2 (94) STM32 L1 (113) STM32W (20)


Synchronous SRAM Pipeline (875) Synchronous SRAM Flow-Through (689)

Synchronous SRAM No-Wait (ZBT) (1246) Synchronous SRAM Automotive (614)

Asynchronous SRAM 5V High-Speed (100) Asynchronous SRAM 5V Low Power (42)

Asynchronous SRAM Automotive (248) Asynchronous SRAM High Speed Low Power (414)

Asynchronous SRAM Lower Power (204) CellularRAM/Pseudo SRAM (34)


Content Requests

The first release of requested content includes more than 600 components covering dozens of individual requests. Highlights include:

Please note these requested components are only available in the Altium Content Vault.

If the parts you requested aren’t among these, the second round of requests will be released early next week, with a third catch up release the week after. Beyond this we hope to keep the turnaround times short (depending on demand). Please also note this is still only a trial, so we won’t be able to guarantee delivery within a certain timeframe.

As usual, all new parts mentioned above are available from the Altium Content Vault and (excluding content requests) as Design Content libraries available here. You can also place components directly from within Altium Designer using the Vault Explorer – where you will also find live supplier links and pricing information from suppliers such as Digi-Key, Farnell/Newark, Mouser and others – connect to the Altium Content Vault to explore further.