| Feature | Rev 1.1 (Old) | Rev 1.2 (Your Board) | | :--- | :--- | :--- | | | Simple RC delay | Supervisory IC (e.g., TPS3808) | | Debug connector | 10-pin ARM JTAG | 20-pin Tag-Connect (no header) | | Pull-up voltage | 5V for I2C bus | 3.3V with level shifters | | Reset circuit | 10k resistor + 1µF cap | Dedicated reset generator (4.65V threshold) |
Imagine you download a file labeled DS-80249-P Rev 1.0.pdf but your board is physically stamped Rev 1.2 . Here is what can go wrong: ds-80249 -p rev 1.2 schematic
Engineers often document changes in a block. For Rev 1.2, expected modifications: | Feature | Rev 1
| Change ID | Description | Impact | |-----------|-------------|--------| | ECO-102 | Replace U6 (LM2596) with U6A (TPS54260) | Lower ripple, higher efficiency | | ECO-107 | Add 10µF ceramic cap near each IC power pin | Reduce decoupling inductance | | ECO-112 | Swap CAN transceiver footprint to SN65HVD230 | Fix bus dominant timeout | | ECO-118 | Relocate R202 (RS-485 terminator) from fixed to jumper-selectable | Increased flexibility | | ECO-122 | Add series resistors (22Ω) to all high-speed digital outputs (SPI, SDIO) | Reduce overshoot/ringing | SDIO) | Reduce overshoot/ringing |
