AthleticsOne board: request for quote

From: IEMI Labs, [email protected] · Date: 4 November 2026 · Reference: IEMI-AO-FP-A

We are asking for a turnkey quote: finish the design of our finish-post board (and the small starter-unit board), make it, assemble it, test it, and deliver boards that are ready to run. When a board arrives, we power it from its battery, put in our microSD card, and it starts our software. We do no setup, soldering or configuration.

All files are in the design pack (zip). The board, part by part: iemilabs.com/build/athleticsone-boards.

1. The board

One rigid-flex board up each finish post: a base section in the steel base box (charger, protection, gauge, boost, tamper), a cell flex to the four cells, a riser into the post, the brain (RV1126B pressed on the track-face wall), a radio section behind the radio window (ESP32-S3, Wi-Fi/BT, and on the home post LTE-M, lightning and NFC), the camera head and a top section with the black-top temperature chips. Both posts carry the same board; the away post leaves the home-only parts unfitted. The starter unit is a separate small ESP32-S3 board with a mic, a flash diode and a charger.

The outline, sections and placement of all 68 parts are fixed (KiCad 10 file, design rule check: 0 violations), each checked against our mechanical CAD. Please keep the outline and part positions, and tell us if anything must move.

2. Parts

Ref	Part	Where
U30	TI BQ24074 1-cell Li-ion charger, 1.5 A, power path, VQFN-16	base
U31	1-cell Li-ion protector (TI BQ2970 class) + dual FET	base
U32	Battery gauge, coulomb counting (MAX17260 class)	base
U33	Charge input: 20 V TVS, reverse protection, fuse	base
U34	TI TPS61023 boost, cells to 5 V (lamp LEDs, sounder) + inductor	base
U35	Load switch: the V1 core is on only while a race is armed (S1 controls it)	base
J1	M8 3-pin A-coded female PCB socket, rear mount through the base end wall (screw-locked charge lead)	base
J4	Two sealed brass feedthrough pins through the base top to the dock pads (charge + / −)	base (home only)
RS1	Current-sense resistor for the gauge, 2512	base
SW1	Omron D2F-01 tamper switch, pressed by a boss on the bolted base floor plate	base
TP2	Factory pads: cell voltage, charge current, gauge I2C	base
BT1	Nickel-strip pad, cell pack + (4 × Samsung INR18650-35E in parallel)	celltab
BT2	Nickel-strip pad, cell pack −, with the pack thermistor beside it	celltab
U1	Rockchip RV1126B-P, FCCSP-409, 0.65 mm pitch; thermal pad to the track-face wall	brain
U2	LPDDR4X 8 Gbit ×32 (1 GB), 200-ball FBGA	brain
U3	Multi-rail regulators for the RV1126B (core, NPU, logic, DDR, 1.8/3.3 V) + inductors	brain
U4	Buck-boost 2.7–4.2 V cells to 3.3 V (TPS63020 class) + inductor	brain
U7	ST LSM6DSOX motion sensor	brain
C1	RV1126B decoupling field (under the chip)	brain
U10	eMMC 5.1 8 GB industrial, 153-ball FBGA; shipped empty (the processor tries the eMMC before the card, so an image here would win): our loader on the card is set to read the card first	brain
J2	microSD socket with a hinged, latched lid (Amphenol 101-00660 class), fitted on every board: our software starts from the card	brain
U90	microSD card power switch (TPS22917-class load switch, 3.3 V, driven by the card power-enable pin) with a 10 kΩ discharge resistor: a stuck card can be power-cycled	brain
U91	microSD ESD and filter array, 6 lines (TPD6F003-class), with 22 Ω series resistors on CLK, CMD and D0–D3 and the card-detect line	brain
TP1	Factory pads: USB 2.0 (writing software), debug serial, boot, rails, current sense	brain
Y1	24 MHz MEMS oscillator (SiTime SiT8008 class, rated to 50,000 g; a quartz crystal is not rated for the shock)	brain
Y2	32.768 kHz MEMS oscillator for the clock (SiTime SiT1533 class, shock-rated)	brain
U8	Microchip ATECC608B security chip, UDFN-8	brain
U9	ID EEPROM 2 kbit	brain
U5	AMPAK AP6256 Wi-Fi 5 + Bluetooth 5 module (certified); the post-to-post link	brain
U11	Wi-Fi 37.4 MHz MEMS oscillator (SiTime SiT8008 class, shock-rated; the AP6256 runs from 37.4 MHz, not 26 MHz), 32 kHz from the processor and RF match	brain
U40	Espressif ESP32-S3-WROOM-1-N8R8 (certified): heat band, lightning clock, taps, gun wake, starter-unit link	mid
U41	Quectel BG95-M3 LTE-M / NB-IoT modem, LCC (alerts to the trainer’s phone off-site)	mid (home only)
U42	MFF2 eSIM, soldered (no SIM socket)	mid (home only)
U43	ScioSense AS3935 lightning sensor IC, MLPQ-16	mid (home only)
L1	Coilcraft MA5532-AE 500 kHz lightning antenna (the AS3935 reference part)	mid (home only)
U44	NXP PN5321A3HN NFC reader, HVQFN-40	mid (home only)
U45	NFC antenna matching network (EMC filter + caps)	mid (home only)
FER1	Ferrite sheet 40 × 40 × 0.3 between the loop and the aluminium track face	mid (home only)
LS1	Magnetic sounder 12 × 12 SMD under the tone holes	mid
Q1	Sounder driver FET	mid
U46	Level shifter for the call-lamp LED data line	mid
TP3	Factory pads: ESP32-S3 USB, boot, enable	mid
MK1	Infineon IM69D130 digital MEMS mic, bottom port over the start-side port (PTFE membrane)	mictab (home only)
LH1	M8 × 0.35 lens holder with a 2.8 mm lens (about 66° × 44° on the OV9281, est.)	head
U20	OmniVision OV9281 global-shutter camera chip, 1280 × 800 at 120 fps	head
U21	Camera LDO 2.8 V (analog)	head
U22	Camera LDO 1.8 V	head
U23	Camera LDO 1.2 V	head
Y20	24 MHz MEMS oscillator for the camera (SiT8008 class, shock-rated)	head
U50	Analog Devices MAX31865 RTD reader, TQFN-20 (black-top temperature)	top (home only)
PT1	Solder pads for the PT1000 element bonded inside the black-anodised top	top (home only)
U52	Sensirion SHT45 humidity and temperature chip, DFN 1.5 × 1.5, behind the vent	top (home only)
U60	Espressif ESP32-S3-MINI-1-N8 (certified): hears the gun, sees the flash, sends the start to the home post	starter
MK2	Infineon IM69D130 digital MEMS mic under the shell’s mic port (printed sound tube)	starter
D20	Vishay BPW34 photodiode under the flash window (printed light pipe)	starter
U61	Microchip MCP73831 LiPo charger, SOT-23-5	starter
BT3	Pads for the leads of a 500 mAh LiPo protected cell (its own protector board: over-charge, over-discharge, short)	starter
SW3	Tactile switch under the printed button	starter
D21	Status LED under the button ring	starter
J5	Two spring pins through the shell floor onto the post’s dock pins	starter
D1	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D2	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D3	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D4	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D5	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D6	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D7	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid
D8	RGB LED with driver, 5050 (WS2812B class), behind the opal lamp slot	mid

Each part’s size, side and position is in athleticsone-board-parts.csv in the pack. Ask before you substitute a part.

3. Scope of work

1. Schematic from Rockchip’s RV1126B reference design and Espressif’s ESP32-S3 hardware design guide and our block list. We review it before layout.
2. Layout in our outline and placement: the RV1126B memory and power routing, impedance-controlled MIPI and USB, and RF for every antenna keep-out. Lay the fast lines on a solid ground plane (inner layer 1, supply on inner layer 2; on a 2-layer section the whole bottom is ground under the module), with one via beside each ground and supply pad and no vias in pads unless you quote filled and capped vias (IPC-4761 type VII); no copper or vias in the antenna keep-out on any layer, none under the card socket; route the impedance lines first (camera MIPI pairs 100 Ω differential, USB 90 Ω, antenna 50 Ω) and add an impedance test coupon. Include the stack-up proposal and DFM, and a rigid-flex drawing (bend lines, stiffeners, coverlay).
3. Fabrication of the rigid-flex board.
4. Sourcing of all parts.
5. Assembly, both sides, with X-ray inspection of the ball-grid parts. Underfill under U1, U2, U10, U5, and flexible-termination capacitors near the board edges (the product takes shocks of about 1000 g). Conformal coating (IPC-CC-830), with the sensors, sockets, connectors and antennas masked.
6. Board support package: U-Boot and a Linux device tree for this layout from Rockchip’s RV1126B SDK, with a real-time (PREEMPT_RT) kernel and the cameras’ frame-sync inputs. A Rockchip SDK image must start from the microSD card. Camera drivers: finish camera OV9281 at 1280 × 800, 100 fps. Flash our ESP32-S3 image (we send it). We add our own software on top.
7. Test of every board to the acceptance list in §5, with a test report per serial number.
8. Deliverables: KiCad (or Altium) source, Gerbers, drill, pick-and-place, BOM, stack-up, test procedure and reports, and the BSP source.

4. “Ready to run” on delivery

This is the most important part of the job:

• Every board arrives assembled, programmed and tested.
• We put our microSD card in (J2, a hinged, latched socket) and power it, and it starts. No soldering, no jumpers, no settings, no flashing.
• The ID EEPROM is written with the serial number and board revision.
• The security chip is provisioned per the steps we will send.

Please quote both battery options:

• A: cells fitted. 4 × Samsung INR18650-35E soldered to the pack pads, protection checked, charged to storage level, and shipped as cells in equipment (UN3481). Please tell us your rules for this.
• B: cells not fitted. A short, polarised battery lead and plug on the pack pads, plus one charged pack per board. Nothing else to do on our side.

5. Acceptance tests (each board, with report)

1. Current-limited first power-on: no short, idle current within the agreed limit.
2. Rails: every power rail within ±3 %.
3. Boot: starts the Rockchip SDK image from the microSD card to a shell over the debug UART; the eMMC is detected and can be written.
4. Finish camera: OV9281 streams 1280 × 800 at 100 fps with no lost frames over 10 minutes, and a frame of a test chart is saved; the frame-sync input triggers frames.
5. Radios: U5 (AMPAK AP6256 Wi-Fi 5 + Bluetooth 5 module); U11 (Wi-Fi 37.4 MHz MEMS oscillator); U40 (Espressif ESP32-S3-WROOM-1-N8R8); U41 (Quectel BG95-M3 LTE-M / NB-IoT modem); U44 (NXP PN5321A3HN NFC reader); U60 (Espressif ESP32-S3-MINI-1-N8): each joins or answers a test station.
6. Sensors and outputs, each read or driven in turn: SW1 (Omron D2F-01 tamper switch), U7 (ST LSM6DSOX motion sensor), U91 (microSD ESD and filter array), U43 (ScioSense AS3935 lightning sensor IC), LS1 (Magnetic sounder 12 × 12 SMD under the tone holes), MK1 (Infineon IM69D130 digital MEMS mic), U50 (Analog Devices MAX31865 RTD reader), U52 (Sensirion SHT45 humidity and temperature chip), MK2 (Infineon IM69D130 digital MEMS mic under the shell’s mic port), D20 (Vishay BPW34 photodiode under the flash window), U61 (Microchip MCP73831 LiPo charger), SW3 (Tactile switch under the printed button), D21 (Status LED under the button ring), D1–D8 (RGB LED with driver).
7. Battery: charges from the charge input at the set voltage; protection cuts off at low voltage and on a short; the gauge reads charge; the thermistor reads.
8. Power: the draw in each state of our day (race armed about 2.6 W, between heats about 0.25 W), so we can check our design review: at least 10 hours, cells aged and cold.
9. Heat: the RV1126B temperature after 1 hour at full load in a 35 °C room, against our estimate.

6. Quantities and timing

Item	Quantity
Rev A boards	2 and 6: please quote both
Budget prices	for 100 and 1,000 boards
Quote wanted	within two weeks of this request
Boards wanted	please give your lead times for design, fabrication and assembly

7. Our design review

Before we order, every board-level number is checked against its target: 18 pass, 5 fixed by the review, 6 to prove on rev A, 0 fail. The full review is on the board page and in the pack. Rev A must let us measure:

• AI engine time per frame
• Ball-grid chips
• Card grade
• Wi-Fi between the two posts
• Fast lines on a solid ground plane
• The two posts agree on time

8. The design pack

Download the design pack (zip): this request, the KiCad 10 board, a 3D model (STEP), side A and side B drawings (PDF), the parts list, placement, the board outline and drawing layers as Gerbers, and the design review.

Questions: [email protected]