wlpuah / RUMBA32 - History

Change Bed MOSFET

Change to SiSS10DN (PowerPAK 1212-8S package). Advantages compared to previous MOSFET:
- Lower RDSon at 4.5V: 3.0/3.6 vs 3.7/4.4
- Vgs can tolerate +20V, not just +10V (so 12V drive is an option)

v1.0B fixes

- Remap HEATER_BED_PIN to PWM capable pin
- Remap FAN_PIN to PWM capable pin
- Tidy labeling of stepper driver jumpers
- Change stepper driver voltage jumper to default to 3V (as per schematic)
- Add back in MOSFET driver voltage select, default to 5V
- Move 5V regulator voltage sense trace away from noise source under regulator IC
- Add pads for optional I2C EEPROM
- Add SMD test points for three unused STM32F4 pins
- General tidying of schematic and PCB routing

Update to v1.0B

Change bed MOSFET to BUK9Y4R4-40E
Remove jumper to select bed MOSFET driver voltage source, hardwired to 5V (BUK9Y4R4-40E has +/- 10V as maximum VGS, so 12V could be damaging).

Routing Done

Routing work finished and PCB tentatively ready for prototyping. Several schematic changes - mostly microcontroller pinout, but also changes to 12V regulator.

Update BOM

Update BOM to more consistent naming
Change 0402 parts to 0603
Simplify resistors / capacitors, minimise line items
Start MOSFET work

Stepper Driver Work

Replace DIP switches with jumpers.
Change stepper driver sockets to support TMC2130 in SPI mode via config jumpers.
Add separate power rail for motors, use diodes to ensure rail is powered by 5V if VIN is not present - protects TMC21x0 from damage if 3V is present or GPIO are driven.

Update LEDs

Add LED for 3V3 rail.
Group LEDs together in dedicated block.