The CM4 requires a 5V DC supply capable of providing up to 3A (depending on the workload). A 94V0 compliant design must handle thermal stress.
Since many manufacturers use the "CM4" label and the "94V0" mark, you must look for the Manufacturer Logo or a specific Model Number printed on the PCB (usually in white silkscreen).
Common Manufacturers & Naming Conventions: cm4 94v0 schematics
Most hobbyist CM4 breakout boards use standard FR-4 (rated 94V0 by default from reputable fabs). However, many low-cost fabs use non-compliant materials. When reviewing CM4 schematics, insisting on 94V0 ensures:
Critical note: No schematic will explicitly show "94V0" as a symbol. It appears in the PCB fabrication notes and stack-up documentation accompanying the schematic. The CM4 requires a 5V DC supply capable
Whether you are designing a new board or reverse-engineering an existing one, every CM4 94V0 schematic must include these essential blocks.
CM4 94V‑0 appears to combine two separate topics often searched together: Critical note: No schematic will explicitly show "94V0"
This write-up explains relevant schematics, safety considerations, and practical guidance for designing PCBs that host a CM4 while meeting UL 94V‑0 expectations.
The reference design is a "proof of concept." For 94V0 production, you need to: