Model B Full Schematic: Raspberry Pi 4

Unlike many consumer electronics, the Raspberry Pi Foundation is relatively open. While the board layout (PCB files) is not fully open source (they are proprietary to protect commercial interests), the full schematic is publicly available under a limited license.

Important Note: There are multiple revisions of the Pi 4 (v1.1, v1.2, v1.4, v1.5). Each has minor changes, primarily in the USB-C power circuitry (to fix the infamous e-marked cable issue) and RAM termination. Ensure you download the schematic matching your board revision. Read the silkscreen on your PCB to verify. Raspberry Pi 4 Model B Full Schematic

Beware of "reverse engineered" schematics on random forums (GitHub Gists or Chinese forums). While well-intentioned, they often contain errors: Important Note: There are multiple revisions of the

Always download the official PDF from raspberrypi.com/documentation/computers/raspberry-pi.html. Always download the official PDF from raspberrypi

| Use Case | Benefit | |---------------|--------------| | Custom HAT design | Identify which GPIO pins are already in use (e.g., I2C, SPI, UART) and their voltage levels. | | Power budget analysis | Trace current paths from PMIC to load; calculate maximum peripheral draw. | | Debugging boot failures | Probe power sequencing rails and check RESET signals against the schematic’s timing. | | Low-level software development | Determine which peripherals share internal buses (e.g., Ethernet and USB bandwidth). | | Repair and rework | Locate test points, fuse elements, and alternative component footprints. |