Chainaxe
About the Chainaxe PCB
Chainaxe is an open source ESP32 PCB design by johnny9, published on GitHub under the CERN-OHL-S-2.0 license. It is a 4-layer board measuring 100 × 70 mm, with 109 components from 78 distinct parts.
Its main chip is the ESP32-S3-WROOM-1-N16R8, from the ESP32 family. Other key parts include the EMC2305-1-AP-TR, AP64501SP-13, TPS22917DBVR, SN74AXC4T774PWR and TMUX1511PWR. By type, the board carries 44 resistors, 21 capacitors, 12 ICs, 8 connectors, 6 transistors and 5 diodes.
From the project
This directory contains the editable Rev A.1 KiCad baseline.
This directory contains the editable Rev A.1 KiCad baseline.
- chainaxe.kicadpro — KiCad project settings and provisional net classes. - chainaxe.kicadsch — annotated preliminary schematic. - chainaxe.kicadpcb — 100 × 70 mm unrouted placement baseline. - chainaxe.kicaddru — conservative prototype rules. - pin-net-audit.csv — exhaustive expected/actual connection contract for every schematic pin. - symbols/ChainAxe.kicadsym and sym-lib-table — project-local custom symbols. - ChainAxe.pretty/ and fp-lib-table` — nine pinned project-local manufacturer-derived/audited footprints.
Main components on the Chainaxe
Chainaxe bill of materials (BOM)
109 components, 78 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | ESP32-S3-WROOM-1-N16R8 Espressif | ESP32-S3-WROOM-1_v1.8 | U1 |
| 1 | EMC2305-1-AP-TR Microchip | EMC2305_QFN16_4x4_P0.65_EP2.2 | U2 |
| 1 | AP64501SP-13 AP64501SP-13 — 3V3 BUCK PROVISIONAL Diodes Incorporated | AP64501_SO8EP | U3 |
| 1 | TPS22917DBVR TPS22917DBVR — HB 3V3 SWITCH Texas Instruments | SOT-23-6 | U5 |
| 1 | SN74AXC4T774PWR SN74AXC4T774PWR — UART/PLUG GATED Texas Instruments | TSSOP-16_4.4x5mm_P0.65mm | U6 |
| 1 | TMUX1511PWR TMUX1511PWR — GATED HB I2C Texas Instruments | TSSOP-14_4.4x5mm_P0.65mm | U7 |
| 1 | SN74LVC126APWR SN74LVC126APWR — FAN PWM ARM Texas Instruments | TSSOP-14_4.4x5mm_P0.65mm | U8 |
| 1 | USBLC6-2SC6 STMicroelectronics | SOT-23-6 | U9 |
| 3 | TPD4E05U06DQAR Texas Instruments | TI_DQA0010A_USON10_2.5x1.0_P0.5 | U10, U11, U13 |
| 1 | SN74LVC1G125DBVR SN74LVC1G125DBVR — RESET GATE Texas Instruments | SOT-23-5 | U12 |
| 4 | 2N7002 2N7002 OPEN-DRAIN PWM Nexperia or approved | SOT-23 | Q1, Q2, Q3, Q4 |
| 2 | DMP3013SFV-7 DMP3013SFV-7 PROVISIONAL Diodes Incorporated | PowerDI3333-8_DMP3013SFV | Q5, Q6 |
| 1 | 0455580003 FAN INPUT 12V ONLY — 0455580003 Molex | 0455580003_THT | J1 |
| 1 | 0353180420 FAN 1 — G 12 T P Molex | 0353180420_THT | J2 |
| 1 | 0353180420 FAN 2 — G 12 T P Molex | 0353180420_THT | J3 |
| 1 | 0353180420 FAN 3 — G 12 T P Molex | 0353180420_THT | J4 |
| 1 | 0353180420 FAN 4 — G 12 T P Molex | 0353180420_THT | J5 |
| 1 | TBD LOGIC IN 12–15V — KEYED TBD TBD | Molex_Micro-Fit_3.0_43650-0200_1x02_P3.00mm_Horizontal | J6 |
| 1 | PM200-2-09-W-4.3 BITMAIN HASHBOARD DATA 2x9 / 18 POS HCTL | PM200-2-09-W-4.3_THT | J10 |
| 1 | USB4105-GF-A USB4105-GF-A — USB2 DEVICE Global Connector Technology | USB4105-GF-A | J30 |
Show 58 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 4 | TBD 10uF 50V X7R Multiple | C_1210_3225Metric | CIN1, CIN2, CIN3, CIN4 |
| 3 | TBD 22uF 10V X7R Multiple | C_0805_2012Metric | COUT1, COUT2, COUT3 |
| 1 | TBD 69.8k 1% — DS41980 TABLE 1 Multiple | R_0402_1005Metric | RFB1 |
| 1 | TBD 22.1k 1% — DS41980 TABLE 1 Multiple | R_0402_1005Metric | RFB2 |
| 1 | CS1213AGF260 BOOT TBD | SW_SPST_CK_RS282G05A3 | SW1 |
| 1 | CS1213AGF260 RESET TBD | SW_SPST_CK_RS282G05A3 | SW2 |
| 1 | BZX84C12LT1G BZX84C12LT1G 12V VGS clamp onsemi | SOT-23 | ZD1 |
| 3 | SS14 SS14 1A 40V Multiple | D_SMA | D1, D2, D3 |
| 1 | SMBJ13A SMBJ13A PROVISIONAL Multiple | D_SMB | D4 |
| 1 | SMBJ18CA SMBJ18CA BIDIRECTIONAL PROVISIONAL Multiple | D_SMB | D5 |
| 1 | SRP5030T-3R3M 3.3uH SRP5030T-3R3M Bourns | L_Bourns-SRP5030TA_5.7x5.2mm | L1 |
| 4 | CL05B104KB54PNC 100n Samsung Electro-Mechanics | C_0402_1005Metric | C1, C2, C100, C102 |
| 1 | CL05B104KB54PNC 100n 25V BOOTSTRAP Samsung Electro-Mechanics | C_0402_1005Metric | C15 |
| 1 | TBD 10n SOFT START Multiple | C_0402_1005Metric | C16 |
| 1 | TBD 2.7n COMP — DS41980 TABLE 1 Multiple | C_0402_1005Metric | C17 |
| 2 | TBD 470uF 25V LOW ESR Multiple | CP_Radial_D10.0mm_P5.00mm | C20, C21 |
| 1 | TBD 1n CT TO VIN — PROVISIONAL Multiple | C_0402_1005Metric | C50 |
| 1 | 1UF 1u U5 VIN BYPASS Multiple | C_0402_1005Metric | C51 |
| 1 | 1UF 1u HB_3V3 LOCAL Multiple | C_0402_1005Metric | C52 |
| 1 | 10NF 10n Multiple | C_0402_1005Metric | C70 |
| 1 | CL05B104KB54PNC 100n U6 VCCA Samsung Electro-Mechanics | C_0402_1005Metric | C80 |
| 1 | CL05B104KB54PNC 100n U6 VCCB Samsung Electro-Mechanics | C_0402_1005Metric | C81 |
| 1 | 1UF 1u Multiple | C_0805_2012Metric | C101 |
| 1 | CL05B104KB54PNC 100n TMUX VDD Samsung Electro-Mechanics | C_0402_1005Metric | C103 |
| 1 | CL05B104KB54PNC 100n U12 VCC Samsung Electro-Mechanics | C_0402_1005Metric | C104 |
| 1 | 1UF 1u EN delay Multiple | C_0402_1005Metric | C110 |
| 1 | TBD 1n 2kV SHIELD Multiple | C_0805_2012Metric | C111 |
| 1 | CL05B104KB54PNC 100nF 50V X7R — U9 VBUS BYPASS Samsung Electro-Mechanics | C_0402_1005Metric | C112 |
| 1 | 0402WGF1003TCE 100k UNI-ROYAL | R_0402_1005Metric | R50 |
| 1 | TBD 100R QOD LINK — PROVISIONAL Multiple | R_0402_1005Metric | R51 |
| 1 | 0402WGF1202TCE 12k 1% UNI-ROYAL | R_0402_1005Metric | R60 |
| 1 | TBD 10.5k COMP — DS41980 TABLE 1 Multiple | R_0402_1005Metric | R65 |
| 1 | 0402WGF1003TCE 100k 1% UNI-ROYAL | R_0402_1005Metric | R70 |
| 1 | TBD 27k 1% Multiple | R_0402_1005Metric | R71 |
| 1 | 0402WGF1003TCE 100k OE DISABLE UNI-ROYAL | R_0402_1005Metric | R80 |
| 1 | 0402WGF330JTCE 33R TX UNI-ROYAL | R_0402_1005Metric | R81 |
| 1 | 0402WGF330JTCE 33R RX PROVISIONAL UNI-ROYAL | R_0402_1005Metric | R82 |
| 1 | 0402WGF1003TCE 100k ESP-SIDE PLUG PULLDOWN UNI-ROYAL | R_0402_1005Metric | R83 |
| 1 | 0402WGF1003TCE 100k EN OFF UNI-ROYAL | R_0402_1005Metric | R84 |
| 7 | 0402WGF4701TCE 4.7k UNI-ROYAL | R_0402_1005Metric | R85, R86, R87, R88, R100, R101, R102 |
| 1 | 0402WGF1002TCE 10k RESET OE DISABLE UNI-ROYAL | R_0402_1005Metric | R89 |
| 3 | 0402WGF4701TCE 4.7k DEFAULT LOW UNI-ROYAL | R_0402_1005Metric | R93, R95, R97 |
| 1 | 0402WGF2202TCE 22k CLK STRAP UNI-ROYAL | R_0402_1005Metric | R103 |
| 1 | 0402WGF3302TCE 33k ADDR STRAP UNI-ROYAL | R_0402_1005Metric | R104 |
| 1 | 0402WGF1003TCE 100k ARM OFF UNI-ROYAL | R_0402_1005Metric | R105 |
| 1 | 0402WGF1003TCE 100k 1% PWM1 SAFE LOW UNI-ROYAL | R_0402_1005Metric | R106 |
| 1 | 0402WGF1003TCE 100k 1% PWM2 SAFE LOW UNI-ROYAL | R_0402_1005Metric | R107 |
| 1 | 0402WGF1003TCE 100k 1% PWM3 SAFE LOW UNI-ROYAL | R_0402_1005Metric | R108 |
| 1 | 0402WGF1003TCE 100k 1% PWM4 SAFE LOW UNI-ROYAL | R_0402_1005Metric | R109 |
| 1 | 0402WGF1002TCE 10k EN pull-up UNI-ROYAL | R_0402_1005Metric | R110 |
| 1 | 0402WGF1002TCE 10k BOOT pull-up UNI-ROYAL | R_0402_1005Metric | R111 |
| 1 | 0402WGF5101TCE 5.1k CC1 UNI-ROYAL | R_0402_1005Metric | R112 |
| 1 | 0402WGF5101TCE 5.1k CC2 UNI-ROYAL | R_0402_1005Metric | R113 |
| 1 | TBD 22R USB D+ Multiple | R_0402_1005Metric | R114 |
| 1 | TBD 22R USB D- Multiple | R_0402_1005Metric | R115 |
| 1 | TBD 1M SHIELD Multiple | R_0402_1005Metric | R116 |
| 4 | 0402WGF1003TCE 100k GATE OFF UNI-ROYAL | R_0402_1005Metric | R200, R203, R206, R209 |
| 4 | RC0402FR-0736KL 36k TACH PULLUP YAGEO | R_0402_1005Metric | R201, R204, R207, R210 |
Chainaxe design files
The KiCad project lives in the johnny9/chainaxe repository on GitHub; these links point at the commit this page was built from.
Chainaxe: common questions
What microcontroller does the Chainaxe use?
The Chainaxe is built around the ESP32-S3-WROOM-1-N16R8, from the ESP32 family.
How big is the Chainaxe PCB?
The Chainaxe measures 100 × 70 mm, has 4 copper layers and is 1.6 mm thick.
How many components are on the Chainaxe?
109 components, from 78 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 Chainaxe design files?
From the johnny9/chainaxe 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 Chainaxe design in my own project?
Yes, under the terms of its CERN-OHL-S-2.0 license, which johnny9 chose for the repository.
Can I test firmware for the Chainaxe without the hardware?
Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug ESP32 firmware against it before you order a PCB.
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