Pi Innovo purchases enclosures, housings and lids, from qualified suppliers of milled blocks, castings, or plastic injection molding. Most PI ECU enclosures are custom designs to fit the PCB, support the connector(s), dissipate heat, and provide protection from harsh environments. Most PI enclosures are environmentally sealed, using a semi-permeable vent.
Pi Innovo purchases Printed-Circuit Boards from qualified suppliers, who build the custom designs using CAD files provided by PI. Many PI PCBs are produced to IPC-A-6012 Class 3 standards. PCBs featuring 4 to 8 conductive layers, and balance contrary thickness constraints from fine-pitch Ball-Grid-Array package resolution and high-currentcapability traces. PCB materials are selected for compatibility with ECU environmental, self-heating, and electrical conditions.
Pi Innovo works closely with contract manufacturing facilities to assemble custom PCBs to IPC-A-6012 Class 3 standards. Components and alternates are controlled by PI designs. Key parts and assembly operations are inspected or tested. Most inspection and testing steps are highly automated, including solder paste thickness, component placement, and In-Circuit Test (probe). Where appropriate, optical inspection is supplemented by X-Ray. The vast majority of components have Surface Mount Device (SMD) packages; through-hole, “odd” components, such as connectors, are soldered with a robotic wand. Microcontrollers are programmed with test software, serial number, and other manufacturing information before proceeding to final assembly.
Final assembly operations and sequencing varies based on product needs. Pi Innovo designs the test vectors appropriate for the ECU: these are often used prior to assembly, and always after assembly is complete. Any conformal coating is applied to the PCB assembly prior to applying heat sink material and fastening to the housing. Any vent and sealant is applied, then the lid is placed to enclose the PCB assembly. ECUs that pass final testing are issued a product label showing the part number and serial number, and may be reprogrammed for the application of the customer. Low-volume customizations are realized by producing one of PI’s standard products, applying the circuit options prior to sealing, and making the appropriate part number changes.