

A repo for all things steam frame hardware.
- Size
- 40 × 40 mm
- Copper layers
- 4
- Thickness
- 1.61 mm
- Parts
- 63
- Nets
- 56
- Pads
- 214
- Tracks, vias
- 383, 144
- Pours
- 7
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 9 Jan 2026
- Updated
- 18 Oct 2026
Overview
Locus is an open-source printed circuit board by Nieko27, from the Nieko27/Frame-Workshop repository on GitHub, published under the CERN-OHL-S-2.0 licence. It is a 4-layer board of 40 × 40 mm with 63 parts on 56 nets, routed with 383 tracks and 144 vias.
It is built around the QMC6309, LSM6DSV16XTR and MCP73831T-2ATI/OT-HXY, with the 2450AT18D0100001E and XL-1615RGBC-RF among its other parts. Its parts include 22 capacitors, 12 resistors, 5 inductors, 4 ICs and 3 connectors. It belongs with the nRF52 and nRF5x boards of this library.
Main components
5QMC6309
WLCSP-4(0.8x0.8)-40℃~+85℃ 16bit 2.5V~3.6V 6uA、10uA I2C ±3.2mT ±3.2mT WLCSP-4(0.8x0.8) 3D Magnetic Sensors ROHSQST3D Magnetic SensorsLSM6DSV16XTR
LGA-14-40℃~+85℃ 1.71V~3.6V 2.6uA 4.5KB IMU (accelerometer + gyroscope) SPI、I2C X,Y,Z X,Y,Z ±16g ±4000dps 运动事件检测、同步与时间戳 LGA-14(2.5x3) Accelerometers ROHSSTMicroelectronicsAccelerometersMCP73831T-2ATI/OT-HXY
SOT-23-5LBattery ManagementHXY MOSFET2450AT18D0100001E
SMD-4PSMD-4P Antennas ROHSJohanson DielectricsAntennasXL-1615RGBC-RF
SMD-4P,1.6x1.5mm-30℃~+85℃ 0.6mm 1.5mm 1.6mm 120° B:460nm~470nm、R:620nm~625nm、G:515nm~530nm Common Anode R:1.8V~2.4V、G:2.6V~3.4V、B:2.6V~3.4V R:100mcd~180mcd、G:350mcd~800mcd、B:120mcd~180mcd R:2000V、G:2000V、B:2000V R:20mA、G:20mA、B:20mA R:50mW、G:70mW、B:70mW R:625nm、B:465nm、G:515nm Top-mount Water Clear SMD-4P,1.6x1.5mm RGB LEDs ROHSXINGLIGHTRGB LEDs
README
KICAD Projects/Primis_FaceTracker/README.mdStatus
| 🛑R&D | hw: EV2 |
|---|
This accessory is experimental. The latest hardware revision is either untested, incomplete, or broken. Capabilities are unproven. Form factor and design requirements may change entirely. Intended for use by hardware contributors.
TODO
- Copper pads under power supply
- Clean up and condense
- ESD Protection
Face Tracker (Headset-Agnostic Version)
Headset-agnostic face tracker. Can be used with Frame by using the USB-C port on the battery.
Current Isseus
Q1 is setup improperly, removing it and R10 as well as bridging the now empty pads solves the issue. Will fix in EV3 along with some changes to layout and LEDs.
Schematics
PCB
EV2
Parts
63| Qty | Value | Footprint | References |
|---|---|---|---|
| 6 | 4.7uF | Capacitor_SMD:C_0603_1608Metric | C2, C7, C9, C18, C20, C21 |
| 5 | 100nF | Capacitor_SMD:C_0402_1005Metric | C1, C8, C10, C12, C13 |
| 4 | 12pF | Capacitor_SMD:C_0402_1005Metric | C3, C4, C14, C16 |
| 4 | LOGO | LOGO | G***, G***, G***, G*** |
| 4 | MountingHole | MountingHole:MountingHole_2.7mm_M2.5 | H1, H2, H3, H4 |
| 4 | TestPoint | TestPoint:TestPoint_Pad_1.0x1.0mm | TP1, TP2, TP3, TP4 |
| 3 | 4.7k | Resistor_SMD:R_0402_1005Metric | R1, R2, R4 |
| 2 | 1.0uF | Capacitor_SMD:C_0402_1005Metric | C11, C29 |
| 2 | 100r | Resistor_SMD:R_0402_1005Metric | R14, R15 |
| 2 | 5.1k | Resistor_SMD:R_0402_1005Metric | R7, R9 |
| 2 | N.C. | Inductor_SMD:L_0402_1005Metric | L3, L5 |
| 1 | 0.8pF | Capacitor_SMD:C_0402_1005Metric | C5 |
| 1 | 0r | Resistor_SMD:R_0402_1005Metric | R16 |
| 1 | 1.0pF | Capacitor_SMD:C_0402_1005Metric | C6 |
| 1 | 100pF | Capacitor_SMD:C_0402_1005Metric | C31 |
| 1 | 10k | Resistor_SMD:R_0402_1005Metric | R10 |
| 1 | 1k | Resistor_SMD:R_0402_1005Metric | R12 |
| 1 | 2.2nH | Inductor_SMD:L_0402_1005Metric | L2 |
| 1 | 2.2uF | Capacitor_SMD:C_0603_1608Metric | C17 |
| 1 | 2450AT18D0100001E | primis2:2450AT18D0100001E | L4 |
| 1 | 32.768kHz | primis2:SC-20S32_768kHz20PPM9pF | Y1 |
| 1 | 32MHz | primis2:NX2016SA-32MHZ-STD-CZS-5 | Y2 |
| 1 | 4.7nH | Inductor_SMD:L_0402_1005Metric | L1 |
| 1 | 470r | Resistor_SMD:R_0402_1005Metric | R13 |
| 1 | 5.6k | Resistor_SMD:R_0402_1005Metric | R11 |
| 1 | Conn_ARM_SWD_TagConnect_TC2030-NL | Connector:Tag-Connect_TC2030-IDC-NL_2x03_P1.27mm_Vertical | J1 |
| 1 | LED | LED_SMD:LED_0603_1608Metric | D1 |
| 1 | LSM6DSV16XTR | LSM6DSV16XTR:LSM6DSV16BXTR | U2 |
| 1 | MCP73831T-2ATI_OT | primis2:MCP73831T-2ATI_OT | U5 |
| 1 | N.C. | Capacitor_SMD:C_0402_1005Metric | C30 |
| 1 | QMC6309 | QMC6309:QMC6309 | U3 |
| 1 | S2B-PH-SM4-TB_LF_SN | primis2:S2B-PH-SM4-TB_LF_SN | J2 |
| 1 | SW_DPST_x2 | primis2:SH-1806SA-A3DW-04 | SW1 |
| 1 | USB_C_Receptacle_USB2.0_16P | Connector_USB:USB_C_Receptacle_HRO_TYPE-C-31-M-12 | J4 |
| 1 | XL-1615RGBC-RF | primis2:XL-1615RGBC-RF | D2 |
| 1 | nRF52833_QDxx | Package_DFN_QFN:QFN-40-1EP_5x5mm_P0.4mm_EP3.6x3.6mm | U1 |
Questions
How big is the Locus PCB?
It measures 40 × 40 mm and has 4 copper layers, 1.61 mm thick.
What parts does the Locus use?
63 parts, built around the QMC6309, LSM6DSV16XTR, MCP73831T-2ATI/OT-HXY and 2450AT18D0100001E. 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 Locus KiCad files?
From the Nieko27/Frame-Workshop repository on GitHub, at the commit this page was made from: the board is KICAD Projects/Previous_Revisions/Primis_LocusEV1/Locus.kicad_pcb and its schematic KICAD Projects/Frame_FaceTracker/Frame_FaceTracker.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Locus design in my own project?
Its repository publishes it under the CERN-OHL-S-2.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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