Rcm
About the Rcm PCB
Rcm is an open source PCB design by Twistiee, published on GitHub under the MIT license. It is a 4-layer board measuring 140 × 70 mm, with 116 components from 25 distinct parts.
By type, the board carries 2 crystals, 2 LEDs, 2 diodes and 1 fuse.
From the project
A CAN-controlled relay driver for a car. 21 universal channels, each of which is simultaneously a low-side output and an input — so the same board builds as a relay controller or as a switch panel, decided in firmware rather than by a different PCB.
A CAN-controlled relay driver for a car. 21 universal channels, each of which is simultaneously a low-side output and an input — so the same board builds as a relay controller or as a switch panel, decided in firmware rather than by a different PCB.
Designed for a rusEFI bus (uaEFI SUPER ECU + uaDASH display), but nothing about it is rusEFI-specific beyond the choice of message IDs.
Rcm bill of materials (BOM)
116 components, 25 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | C115962 8MHz | Crystal_SMD_5032-2Pin_5.0x3.2mm | Y1 |
| 1 | C32346 32.768kHz | Crystal_SMD_3215-2Pin_3.2x1.5mm | Y2 |
| 2 | 10uF_25V | C_0805_2012Metric | C_3V3I, C_5V |
| 14 | 100nF | C_0805_2012Metric | C_3V3O, C_IMU1, C_IMU2, C_M1, C_M2, C_M3, C_M4, C_M5 +6 |
| 4 | 20pF | C_0805_2012Metric | C_Y1A, C_Y1B, C_Y2A, C_Y2B |
| 1 | C19078719 PPTC_1A | R_1812_4532Metric | F1 |
| 1 | WAVESHARE-IN | WaveshareBuck_IN_2x2_P3.50mm | JB1 |
| 1 | C37208 WAVESHARE-OUT | WaveshareBuck_OUT_3x3_P2.54mm | JB2 |
| 1 | CAN_A | TerminalBlock_KF2EDG-3.5-3P_1x03_P3.50mm_Horizontal | J_CAN1 |
| 1 | CAN_B | TerminalBlock_KF2EDG-3.5-3P_1x03_P3.50mm_Horizontal | J_CAN2 |
| 1 | CH1-7 | TerminalBlock_KF2EDG-3.5-7P_1x07_P3.50mm_Horizontal | J_CH1 |
| 1 | CH8-14 | TerminalBlock_KF2EDG-3.5-7P_1x07_P3.50mm_Horizontal | J_CH2 |
| 1 | CH15-21 | TerminalBlock_KF2EDG-3.5-7P_1x07_P3.50mm_Horizontal | J_CH3 |
| 24 | 1M | R_0805_2012Metric | R_AH1, R_AH2, R_AH3, R_SH1, R_SH2, R_SH3, R_SH4, R_SH5 +16 |
| 24 | 270k | R_0805_2012Metric | R_AL1, R_AL2, R_AL3, R_SL1, R_SL2, R_SL3, R_SL4, R_SL5 +16 |
| 2 | 5.1k | R_0805_2012Metric | R_CC1, R_CC2 |
| 2 | 1k | R_0805_2012Metric | R_LED1, R_LED2 |
| 21 | 10k | R_0805_2012Metric | R_PU1, R_PU2, R_PU3, R_PU4, R_PU5, R_PU6, R_PU7, R_PU8 +13 |
| 3 | TPL7407L | TSSOP-16_4.4x5mm_P0.65mm | U_DRV1, U_DRV2, U_DRV3 |
| 3 | 74HC165 | SOIC-16_3.9x9.9mm_P1.27mm | U_SI1, U_SI2, U_SI3 |
Show 5 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 3 | 74HC595 | SOIC-16_3.9x9.9mm_P1.27mm | U_SO1, U_SO2, U_SO3 |
| 1 | GRN | LED_0805_2012Metric | D_LED1 |
| 1 | RED | LED_0805_2012Metric | D_LED2 |
| 1 | C8678 SS34 | D_SMA | D1 |
| 1 | C353454 SMAJ33A | D_SMA | D2 |
Rcm design files
The KiCad project lives in the Twistiee/rcm repository on GitHub; these links point at the commit this page was built from.
- Layoutrcm.kicad_pcb
- Schematicrcm.kicad_sch
- BOMmfg/bom_jlc.csv
Rcm: common questions
How big is the Rcm PCB?
The Rcm measures 140 × 70 mm, has 4 copper layers and is 1.6 mm thick.
How many components are on the Rcm?
116 components, from 25 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Rcm design files?
From the Twistiee/rcm repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Rcm design in my own project?
Yes, under the terms of its MIT license, which Twistiee chose for the repository.