Industries
Power Electronics PCB
Heavy copper, metal core and thermal management for high-power circuits.
Power electronics PCBs carry high currents, dissipate significant heat and manage voltage levels that create safety and reliability concerns not present in standard signal-level boards. Battery management systems (BMS), motor drives, inverters, DC-DC converters, power supplies and charger circuits all place unique demands on the PCB: heavy copper for current capacity, thermal management through the substrate, high-voltage isolation between circuit sections, and mechanical robustness for vibration-prone environments like electric vehicles and industrial equipment.
BMS PCB requirements
A battery management system PCB monitors individual cell voltages, manages charge balancing, controls charge/discharge switching and communicates battery state to the system controller. BMS PCBs present several manufacturing challenges: high-voltage isolation between the cell monitoring circuits and the system communication interface (often 500V+ isolation), mixed-signal design combining precision analog measurement with digital communication, and thermal management for balancing resistors and MOSFET switches that dissipate significant power during active balancing.
BMS boards for electric vehicles must also meet automotive reliability requirements — temperature cycling from -40°C to +125°C, vibration endurance, and product lifetimes exceeding 10 years. Heavy copper (2-4 oz) on power layers, high-Tg laminates (Isola 370HR or equivalent) and automotive-grade surface finishes are standard specifications.
Heavy copper for power distribution
Power electronics boards carrying 10, 20 or 50+ amps cannot use standard 1 oz copper traces — the required trace width would consume the entire board area. Heavy copper from 2 oz to 10 oz provides the current-carrying capacity needed within practical trace widths. A 100-mil wide trace in 4 oz copper carries approximately 12 amps with a 20°C temperature rise — the same current in 1 oz copper would require a 400-mil wide trace or a copper bus bar.
Heavy copper layers can be combined with standard-weight copper signal layers in the same board. A typical power electronics stackup might use 3 oz copper on two power distribution layers and 1 oz copper on signal and control layers. The fabrication process accommodates different copper weights on different layers through selective etching and plating parameters.
Thermal management
Power electronics generate concentrated heat at switching devices, current-sense resistors, inductor pads and connector interfaces. The PCB must conduct this heat away from the components to prevent junction temperatures from exceeding safe operating limits. Strategies include thermal via arrays beneath high-power components (connecting to internal copper planes that spread heat laterally), heavy copper planes that act as heat spreaders, and metal-core PCB substrates (aluminum or copper core) for single-layer power circuits where maximum thermal conductivity is needed.
High-voltage isolation
Power electronics boards often carry high voltages alongside low-voltage control circuits. Creepage and clearance distances between high-voltage and low-voltage sections must comply with the applicable safety standard (IPC-2221 for general PCB, UL 60950/62368 for IT equipment, IEC 60601 for medical devices). These requirements affect trace spacing, slot placement, board outline geometry and component placement. The fabricator must maintain these clearances throughout the manufacturing process — including ensuring that solder mask, copper residues and board edge conditions do not reduce the effective isolation distance.
Request a power electronics PCB quote
Specify copper weights per layer, thermal management requirements, high-voltage isolation standards and operating environment. Upload your design files for a DFM-reviewed quotation.