How Onshape and Altium Are Erasing the ECAD-MCAD Divide

The modern market, driven by demand for integrated, intelligent electromechanical products (like wearables, smart home devices, and industrial sensors), pressures engineering teams to accelerate development and innovation.

Historically, the slow, sequential “throw it over the wall” method created bottlenecks, isolating MCAD and ECAD engineers. The electrical team finalized the PCB design, then handed a static file (e.g., IDF) to the mechanical team for enclosure design. Any subsequent change requires a time-consuming, error-prone cycle of re-exporting, re-importing, and manual alignment checks, causing delays and increasing the risk of prototype failure.

Accelerated innovation requires eliminating these barriers by establishing a unified, concurrent, and agile workflow where MCAD and ECAD teams co-design in real-time.

This is now possible through the Onshape Altium Connector, a cloud-to-cloud integration between Onshape PCB Studio (cloud-native MCAD) and Altium 365 (cloud-based platform for PCB design). This integration replaces static file hand-offs with a direct, continuous digital thread, allowing engineers to resolve integration challenges faster and get to market sooner.

The Anatomy of a Broken Process: Why Legacy Integration Fails

For decades, the industry relied on intermediary ECAD-MCAD file formats to bridge the gap between design systems. While useful then, these formats now severely limit modern design cycles due to their inherent limitations.

Intermediate Data Format (IDF) Limitations

The Intermediate Data Format (IDF) was one of the earliest standards specifically created for ECAD-MCAD exchange. Its initial appeal was its incredible simplicity and lightweight nature, making it easy to transmit. However, this simplicity is precisely its downfall.

• Rudimentary 2.5D Abstraction: IDF can only provide basic 2.5D bounding boxes, meaning complex parts like curved connectors, irregular heat sinks, or BGAs are simplified to simple blocks representing their maximum size, discarding the critical 3D geometry.
• Data Fragmentation: The required format forces simultaneous management of two files, one for the board outline/hole locations and a separate component library. This fragmentation frequently causes versioning errors and data misalignment.
• False Collision Alerts and Missed Interferences: Oversized geometric representations cause MCAD engineers two problems: false collision alerts when the bounding box "collides" but the actual component fits, leading to unnecessary revisions; and, more dangerously, missed interferences from complex features extending past the bounding box, only discovered during expensive physical prototyping.
• Lack of Parametric Intelligence: IDF files are purely geometric snapshots. They carry no parametric intelligence, meaning the mechanical engineer cannot easily modify the model or understand the design intent behind a component placement without contacting the ECAD engineer.

Incremental Design Exchange (IDX) Limitations

The Incremental Design Exchange (IDX) format was developed as an attempt to address some of the time-wasting inefficiencies of IDF, specifically by eliminating the need to send massive, full board layout files for every minor change.

• Step in the Right Direction, But Still File-Bound: IDX allows teams to pass only the incremental changes such as a component move, a new mounting hole, or an updated board shape rather than the entire board layout. This speeds up the data transfer, but it does not fix the underlying problem of data fidelity.
• Reliance on Discrete File Generation: Despite being "incremental," IDX still fundamentally relies on the manual, discrete generation and consumption of files. The ECAD engineer must consciously "export" the IDX file, and the MCAD engineer must manually "import" and apply it. This manual handoff process is error-prone, asynchronous, and breaks the continuity of the design workflow.
• Asynchronous Communication and Shared Drives: The process still relies on passing data back and forth, often through network folders, email, or shared drives. This creates a data synchronization nightmare, making it difficult to determine which version is the absolute, most current “source of truth.” The resulting latency in communication is measured in hours or even days, effectively stalling parallel engineering efforts.

Legacy methods, relying on static, non-intelligent files passed manually, fundamentally fail as reliable conduits for the dynamic, iterative collaboration needed in modern product development. This “file trap” causes latency, version control errors, false positives, and costly physical prototype failures.

Onshape PCB Studio Meets Altium 365

The Onshape Altium Connector represents a “cloud meets cloud” paradigm. Unlike legacy software that requires sharing files, this direct, secure API connection eliminates the file-based workflow, enabling new capabilities.

Bi-Directional Synchronization: Electrical and mechanical teams can now exchange board outlines, mounting hole locations, and component placements using their native credentials. The synchronization is fully bi-directional. 

Unified Component Libraries: Shared MCAD-ECAD libraries automatically populate components in full 3D. Both disciplines are guaranteed to be working with the exact same, highly detailed representation of a part, complete with accurate solder fillets and pin heights, ensuring that what you see on the screen is exactly what will roll off the assembly line.

High-Fidelity Visibility (Without the Bloat): The Altium Connector solves for bloated file formats by pulling in detailed decals of the primary and secondary board surfaces. MCAD engineers can natively see silkscreens, external etch, solder masks, test points, and hidden vias precisely mapped onto the board geometry. They get the high-fidelity visual context they need to design without making the 3D assembly file size exorbitant.

Synchronized Keep-Outs & Enclosure Constraints: Mechanical engineers can define complex board outlines, keep-out/keep-in areas, and strict height restrictions based on the physical enclosure design directly inside Onshape. This constraint data is pushed natively to Altium, acting as a digital fence. It prevents electrical engineers from ever placing components in restricted zones to begin with, shifting collision detection from a late-stage failure to an early-stage preventative measure.

Visual History & Traceability: Combining Altium 365's integrated visual notification with Onshape's built-in Product Data Management (PDM) creates a visual project history. Teams can visually inspect the differences between revisions, tracking exactly who made a change, when they made it, and why.

Supply Chain Traceability: Altium 365 features a robust ActiveBOM system that integrates directly with component data providers like Octopart and SiliconExpert, providing real-time lifecycle status, stock availability, and pricing. Thanks to the cloud-to-cloud integration, this supply chain intelligence can trigger rapid changes in both ECAD and MCAD.

The End of Siloed Engineering

The industry is reaching an inflection point. Engineering teams that adopt real-time, cloud-native collaboration will out-innovate, out-design, and out-pace competitors who are still manually passing static IDF files through archaic translation tools.

Explore Onshape PCB Studio today and see how the Altium Connector can revolutionize your team's workflow.