Analysis of Motor Control Development: Examination of Board Architecture
Sierra Circuits Unveils Innovative High-Current Motor Control PCB Design
Sierra Circuits, a leading PCB fabricator, has recently showcased a groundbreaking motor control board design, demonstrating the company's expertise in handling high-current systems. This Sierra Circuits case study on high-current motor control PCBs highlights several specific fabrication rules and design constraints critical for safe and efficient operation.
The PCB, designed for automated systems with more than one axis, operates at a peak current of 30 amps and an average current of 20 amps. To handle these high currents, the board employs thicker copper layers, such as 2 oz/ft² or more, to reduce trace resistance and heat generation. Wide traces and planes are also used to distribute current evenly and minimize localized heating.
Thermal management is another crucial aspect of this design. Thermal relief patterns, heat dissipation features like thermal vias, heat sinks, and large copper pours help spread heat from power components like MOSFETs or motor drivers. Through-hole plating and via sizing are optimized to conduct heat away from components and between layers efficiently.
High-current components are placed strategically to minimize trace length and loop area, reducing parasitic inductance and resistance, thus improving efficiency and reducing EMI. Clearance and creepage are also carefully considered to prevent arcing and ensure safety.
Signal integrity and noise reduction are essential for the precise control required in motor control applications. Sensitive control signals are routed separately from high-current paths, often with ground shielding and filtering components to maintain signal integrity.
The motor control board design includes a brushed DC motor controller, which offers efficient control over the motor's torque and speed. The board is an 8-layered board with dimensions of 192 mm x 141 mm, and over a thousand components are incorporated into this design.
To facilitate the precise movement of flexible arms or wings, a robotic motion controller is implemented in this design. This board is also used in various propulsion systems such as electric bikes, electric cars, fuel pumps, and motorbikes.
The board is an IPC class-3 design, undergoing thorough inspection for high quality. The IPC Class 3 Design Guide, containing 8 chapters, 23 pages, and a 35-minute read, details IPC guidelines for manufacturing defects, assembly processes, and acceptance criteria. The board material used is FR-370 HR, offering maximum thermal performance and reliability.
While the specific Sierra Circuits document was not found in the search results, these industry-standard guidelines are consistent with what leading PCB fabricators like Sierra Circuits emphasize for high-current motor control designs. This innovative motor control board design underscores Sierra Circuits' commitment to pushing the boundaries of PCB technology and delivering high-quality, reliable solutions for their clients.
This innovative motor control board design by Sierra Circuits, a leading PCB fabricator, utilizes controlled impedance technology to manage trace resistance and improve efficiency. The board's success in handling high currents is due, in part, to the implementation of specific rules in designing for controlled impedance, such as the use of thicker copper layers and wide traces. The technology significantly contributes to the board's effective thermal management and safe operation.
