4 layers50 × 65 mm
Link mod lr brd
semtronik/link-hardware
Open hardware for the Semtronik Link devices: ESP32-S3 base board, interface modules and enclosure. KiCad and Fusion sources, CERN-OHL-S v2.
18 parts
4 layers94 × 65 mm
Link base brd
semtronik/link-hardwareOpen hardware for the Semtronik Link devices: ESP32-S3 base board, interface modules and enclosure. KiCad and Fusion sources, CERN-OHL-S v2.
- Size
- 94 × 65 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 115
- Nets
- 91
- Pads
- 393
- Tracks, vias
- 845, 162
- Pours
- 10
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 31 Aug 2026
- Updated
- 12 Oct 2026
Overview
Link base brd is an open-source printed circuit board by semtronik, from the semtronik/link-hardware repository on GitHub. It is a 4-layer board of 94 × 65 mm with 115 parts on 91 nets, routed with 845 tracks and 162 vias.
It is built around the ESP32-S3-WROOM-1-N16R8, CAT4104V-GT3 and BQ24074RGTR, with the MAX17048G+T10, PCF8563T/5 and TPS62821DLC among its other parts. Its parts include 31 resistors, 23 capacitors, 6 ICs, 6 connectors and 5 diodes. It belongs with the interfaces and adapters boards and the ESP32 boards of this library.
Main components
11
ESP32-S3-WROOM-1-N16R8
SMD,25.5x18mm-103.5dBm -40℃~+65℃ 2.4GHz 20.5dBm 355mA 3V~3.6V 95mA ESP32-S3R8 On-board PCB Antenna UART、SPI、I2C、GPIO、I2S、USB SMD,25.5x18mm WiFi Modules ROHSEspressif SystemsWiFi Modules
CAT4104V-GT3
SOIC-8-40℃~+85℃ 175mA 2% 25V 3V~5.5V 4 Over-Temperature Protection (OTP) PWM SOIC-8 LED Drivers ROHSonsemiLED Drivers
BQ24074RGTR
QFN-16-EP(3x3)-40℃~+125℃ 1 1.5A 4.2V 4.35V~10.2V 6.5uA Charging IC Lithium Battery Not supported Support QFN-16-EP(3x3) Battery Management ROHSTexas InstrumentsBattery Management
MAX17048G+T10
DFN-8-EP(2x2)-40℃~+85℃ 1 2.5V~4.5V 3uA I2C Lithium Battery Not supported Not supported DFN-8-EP(2x2) Battery Management ROHSMaxim Integrated (Analog Devices)Battery ManagementPCF8563T/5
SO-8-40℃~+85℃ 0.25uA 1V~5.5V Battery low-voltage detection、Programmable clock output、Alarm function、Countdown timer I2C Yes SO-8 Real Time Clocks ROHSNXP SemiconductorsReal Time Clocks
TPS62821DLC
UncategorisedTexas Instruments
1N4148W
SOD-123150mA 1A 1V@50mA 1uA@75V 400mW 4ns 75V Independent SOD-123 Switching Diodes ROHSSTMicroelectronicsSwitching DiodesM2.5
-0.45mm 2.5mm 2mm 5mm DIN934 Hex M2.5X0.45 Nickel plated Silver white - Hexagonal nutsShuntianHex Nut
AO3401A
SOT-231 P-Channel 14nC@10V 30V 47mΩ@10V、60mΩ@4.5V、85mΩ@2.5V 4A 55pF 645pF 80pF 900mV SOT-23 MOSFETs ROHSAlpha & Omega SemiconductorMOSFETsAO3400A
SOT-23-55℃~+150℃ 1 N-channel 1.45V 1.4W 30V 48mΩ@2.5V 5.7A 50pF 630pF 75pF 7nC@10V N-Channel SOT-23 MOSFETs ROHSAlpha & Omega SemiconductorMOSFETs
PRTR5V0U2X
SOT-143-55℃~+125℃ 0.3pF、0.8pF 100W 10V、15V 5V 6.5V 6A 80nA ESD IEC 61000-4-2、IEC 61000-4-5、IEC 61000-4-4 Three channels Unidirectional SOT-143 ESD and Surge Protection (TVS/ESD) ROHSTECH PUBLICESD And Surge Protection (TVS/ESD)
README
board/link-mod-lr-brd/README.mdlink-mod-lr-brd
LoRa interface module of the Link platform. Plugged onto the base board, it makes a Link-LR: a LoRa P2P radio on 868/915 MHz.
Part of link-hardware. See the repository README for
naming, versioning and release conventions.
Design
| Function | Part |
|---|---|
| LoRa radio | Seeed Wio-SX1262 module (Semtech SX1262, TCXO, RF switch) |
| Base interface | 2×10 header, 2 mm pitch |
The board is 60 × 50 mm. It carries the radio module and little else: decoupling, pull-ups and the connector to the base. The antenna leaves through a u.FL to SMA pigtail to the enclosure.
Connectors
| Ref | Role |
|---|---|
| J2 | To the base board's J3: power (+3V3, +VSYS, +VNR), I²C and the eight module I/Os IO_MOD01–IO_MOD08, which carry the radio's SPI and control lines |
| J1, J3 | 1×8 sockets, 2.54 mm — not fitted on the Link-LR |
J2 mates with the base's J3, the platform contract: its pinout, the mounting footprint and the 60 × 50 mm outline are what every interface module must satisfy.
Radio wiring
| Module I/O | SX1262 |
|---|---|
IO_MOD01 | MISO |
IO_MOD02 | SCK |
IO_MOD03 | MOSI |
IO_MOD04 | RF_SW |
IO_MOD05 | NRESET |
IO_MOD06 | NSS |
IO_MOD07 | DIO1 (interrupt) |
IO_MOD08 | BUSY |
The SX1262 drives the module's RF switch itself through DIO2, and powers
its TCXO through DIO3; neither pin leaves the module. The module's RF_SW
input must stay high for DIO2 to choose the direction: R3 (10 k to
+3V3) holds it, so the firmware leaves that pin alone.
Status
Pre-production (0.x). Revision 0.2.0 is validated on our own bench; all
interfaces may still change without a MAJOR bump.
Files
Design sources are the KiCad project in this folder. outputs/ holds the
fab-agnostic exports of the last freeze — schematic PDF, BOM, position file,
gerbers and STEP.
They are regenerated by running outputs.kicad_jobset from the KiCad
project window. Output names carry the revision read from the schematic
title block, so they cannot drift from the sources.
Parts
115| Qty | Value | Footprint | References |
|---|---|---|---|
| 26 | TP-PAD-D1.0mm | TestPoint:TestPoint_THTPad_D1.0mm_Drill0.5mm | TP1, TP2, TP10, TP13, TP14, TP15, TP16, TP17, TP18, TP19, TP20, TP21, TP22, TP23, TP24, TP25 +10 |
| 10 | 100k | Resistor_SMD:R_0603_1608Metric | R3, R4, R5, R6, R7, R11, R14, R32, R33, R34 |
| 10 | 10k | Resistor_SMD:R_0603_1608Metric | R1, R15, R16, R17, R18, R19, R20, R23, R24, R25 |
| 7 | 10uF | Capacitor_SMD:C_0805_2012Metric | C1, C2, C4, C9, C12, C21, C23 |
| 6 | 0.1uF | Capacitor_SMD:C_0603_1608Metric | C6, C8, C13, C22, C24, C25 |
| 4 | 1N4148W | Diode_SMD:D_SOD-123 | D1, D2, D3, D4 |
| 4 | M2.5 | MountingHole:MountingHole_2.7mm_M2.5 | H3, H4, H5, H6 |
| 4 | Standoff_M2.5x7 | MountingHole:WA-SMSI_9774070151 | H1, H2, H7, H8 |
| 3 | 15pF | Capacitor_SMD:C_0603_1608Metric | C15, C16, C18 |
| 2 | 0.75A | Fuse:Fuse_1206_3216Metric | F1, F2 |
| 2 | 1uF | Capacitor_SMD:C_0603_1608Metric | C14, C17 |
| 2 | 22R | Resistor_SMD:R_0603_1608Metric | R21, R22 |
| 2 | 22uF | Capacitor_SMD:C_0805_2012Metric | C10, C11 |
| 2 | 5.1k | Resistor_SMD:R_0603_1608Metric | R30, R31 |
| 2 | AO3401A | Package_TO_SOT_SMD:SOT-23 | Q1, Q3 |
| 2 | TP-PAD-D1.0mm | TestPoint:TestPoint_Pad_D1.0mm | TP11, TP12 |
| 1 | 1.5k | Resistor_SMD:R_0603_1608Metric | R8 |
| 1 | 1.8k | Resistor_SMD:R_0603_1608Metric | R9 |
| 1 | 10nF | Capacitor_SMD:C_0603_1608Metric | C5 |
| 1 | 10uF | Capacitor_SMD:C_0603_1608Metric | C3 |
| 1 | 120pF | Capacitor_SMD:C_0603_1608Metric | C7 |
| 1 | 150k | Resistor_SMD:R_0603_1608Metric | R13 |
| 1 | 1M | Resistor_SMD:R_0603_1608Metric | R10 |
| 1 | 3.3k | Resistor_SMD:R_0603_1608Metric | R35 |
| 1 | 32.768kHz | Crystal:Crystal_SMD_2012-2Pin_2.0x1.2mm | Y1 |
| 1 | 3k | Resistor_SMD:R_0603_1608Metric | R2 |
| 1 | 453k | Resistor_SMD:R_0603_1608Metric | R12 |
| 1 | 470nH 4.5A | Inductor_SMD:L_Murata_DFE201610P | L1 |
| 1 | 52271-0679 | Connector_Molex:522710679 | J6 |
| 1 | 54132-4062 | Connector_Molex:54132-4062_1 | J7 |
| 1 | AO3400A | Package_TO_SOT_SMD:SOT-23 | Q2 |
| 1 | BQ24074RGT | Package_DFN_QFN:VQFN-16-1EP_3x3mm_P0.5mm_EP1.6x1.6mm_ThermalVias | U1 |
| 1 | CAT4104V-GT3 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U6 |
| 1 | CON-Header-2x03-2.54mm-VR | Connector_PinHeader_2.54mm:PinHeader_2x03_P2.54mm_Vertical | J2 |
| 1 | CON-Header-2x10-2mm-HR | Connector_PinSocket_2.00mm:PinSocket_2x10_P2.00mm_Vertical_SMD | J3 |
| 1 | ESP32-S3-WROOM-1-N16R8 | Espressif:ESP32-S3-WROOM-1 | U4 |
| 1 | JST-XH-3P | Connector_JST:JST_XH_B3B-XH-AM_1x03_P2.50mm_Vertical | J1 |
| 1 | MAX17048G+ | Package_DFN_QFN:TDFN-8-1EP_2x2mm_P0.5mm_EP0.8x1.2mm | U2 |
| 1 | PCF8563T | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U5 |
| 1 | PRTR5V0U2X | Package_TO_SOT_SMD:SOT-143 | D6 |
| 1 | SW-SPST-EVQPUA02K | Button_Switch_SMD:Panasonic_EVQPUJ_EVQPUA | SW1 |
| 1 | TPS62821 | Package_SON:Texas_VSON-HR-8_1.5x2mm_P0.5mm | U3 |
| 1 | USB_C_Receptacle_USB2.0_16P | Connector_USB:USB_C_Receptacle_GCT_USB4105-xx-A_16P_TopMnt_Horizontal | J5 |
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Questions
How big is the Link base brd PCB?
It measures 94 × 65 mm and has 4 copper layers, 1.6 mm thick.
What parts does the Link base brd use?
115 parts, built around the ESP32-S3-WROOM-1-N16R8, CAT4104V-GT3, BQ24074RGTR and MAX17048G+T10. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Link base brd KiCad files?
From the semtronik/link-hardware repository on GitHub, at the commit this page was made from: the board is board/link-base-brd/link-base-brd.kicad_pcb and its schematic board/link-base-brd/core.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Link base brd design in my own project?
Its repository states no licence, so its author keeps all rights: ask semtronik before reusing the design.