---
tags: [project-drogheda, bom, sourcing, hardware]
project: Project Drogheda
author: Helgen CTO
date: 2026-06-20
status: Active
---

# BOM Maestro — HBOX + Gabinete (24 V)

> Updated master BOM for the **24 V** Drogheda unit (the dominant ICAVE variant).
> Costs in **MXN**, from `Selección de componentes para gabinete2.xlsx` and the
> H-BOX BOM sheet. This supersedes the older loose BOM. For 12/48/110/230 V
> variants only the cabinet power/protection parts change (see source sheet).

> **Why this exists:** the earlier BOM drifted from reality. This pins the **as-built**
> parts (so diagnosis/PCB work targets the right hardware) and flags the
> **change-list** for the production fix.

## 1. HBOX — internal unit (per unit, 24 V)

| # | Item | Marca / Modelo | Qty | MXN | Notes |
|---|---|---|---:|---:|---|
| 1 | H-BOX Case | Helgen Series1 (**ASA print**) | 1 | 100 | UV-stable, ~95–100 °C — adequate |
| 2 | H-BOX Top | Helgen Series1 (**ASA**) | 1 | 50 | |
| 3 | DC PSU bracket | Helgen Series1 (ASA) | 1 | 20 | |
| 4 | Battery Case | Helgen Series1 (ASA) | 1 | 30 | houses 18650 |
| 5 | SIM | Telcel micro | 1 | 100 | per-unit data plan |
| 6 | **GNSS RTK** | Ardusimple simpleRTK2B **Pro** (AS-RTK2B-PROF9P-L1L2-NH-00) | 1 | 3,340 | ZED-F9P |
| 7 | **4G/NTRIP** | Ardusimple 4G NTRIP Master (AS-XBEE-4G-NA-UFL-00) | 1 | 2,440 | XBee LTE |
| 8 | **MCU watchdog** | DFRobot STM32F411 Blackpill | 1 | 104 | runs `blackpillrtkcode_v2` |
| 9 | GNSS antenna | Ardusimple AS-ANT2B-ANN-L1L2-50SMA | 1 | 700 | multiband |
| 10 | LTE antenna | Unit Electronics AR1582 (SMA→IPEX) | 2 | 42 | 4G diversity |
| 11 | Headers F 6/8/10-pin | 2.54 mm | 1ea | 10 | board interconnect |
| 12 | **5 V supply** | **Mean Well SD-15B-05** (18–36 V→5 V, 3 A) | 1 | 300 | ✅ industrial — keep |
| 13 | Boost / charger | Adafruit **PowerBoost 1000C** (2465) | 1 | 400 | battery path — review |
| 14 | **Ignition cond.** | DFRobot **DFR1015** buck | 1 | 106 | **v3: ON-BOARD** — GX16 pin 3 = raw ignition (12–24 V) → DFR1015 → PA5 (digital) |
| 15 | **Battery** | Hyvel **18650 1S4P** (FG-0889, 3.6 V) | 1 | 204 | ⚠ charge ≤45 °C — decide |
| 16 | Status LED + holder | Steren 5 mm + bezel | 1 | 3 | PB0 path |
| 17 | Resistor | 1.5 kΩ (use TBC — see watchdog-schematic) | 1 | 1 | verify value |
| 18 | **HBOX↔cabinet** | **GX16-5** macho/hembra | 1 | 22 | ✅ locking — keep |
| 19 | Watchdog discretes | 2N3904, IRF9540N, 2N7000, R (1k/10k/220Ω) | — | — | → consolidate on PCB |
| 20 | Dupont terminals | red + black | 2 | 4 | ⚠ vibration — eliminate |
| 21 | Wire, glands, screws, label, switch | genérico / Steren | — | ~110 | NPT 3/8 gland |
| | **HBOX subtotal** | | | **≈ 8,041** | |

## 2. Gabinete — cabinet (per unit, 24 V)

| Item | Marca / Modelo | Qty | MXN |
|---|---|---:|---:|
| Enclosure IP67 (ABS) | Yetlebox **P3901** (39×29×16) | 1 | 1,435 |
| DIN rail | Weidmüller TS 35×7.5 | 1 | 50 |
| Neutral terminals | Weidmüller WDU 2.5 | 5 | 58 |
| Ground terminals | Weidmüller WPE4 | 4 | 154 |
| Fuse-holder terminal | Phoenix **PT 6-FSI/C** (3212166) | 3 | 900 |
| End stops | Wago 249-116 | 4 | 56 |
| Ignition SSR | Weidmüller **TOS 24VDC 2A** | 1 | 684 |
| Surge (SPD) | Phoenix **TTC-6-TVSD-C-24DC-PT-I** | 2 | 1,076 |
| Breaker | Phoenix **TMC 81C 05A** | 1 | 484 |
| **Supply → 24 V** | Mean Well **DDR-60G-24** | 1 | 748 |
| Fuse (blade) | automotriz **2 A** | 3 | 6 |
| Cable / ferrules / glands / labels | Indiana / Weidmüller / Helgen | — | ~110 |
| Shipping to port | — | 1 | 600 |
| **Cabinet subtotal** | | | **≈ 6,365** |

**≈ Total per 24 V unit: ~14,400 MXN** (HBOX ~8,041 + cabinet ~6,365). An
alternate supplier ("Israel" column in the sheet) shows ~1,284 MXN/cabinet
savings at 24 V — sourcing decision lives here in `09_`.

## 3. ✅ What's already good (don't re-buy / don't duplicate)

- **Cabinet** is industrial-grade: SPD + breaker + isolated SSR ignition + Mean
  Well 24 V. The HBOX needn't re-implement input surge/protection.
- **SD-15B-05** (24→5 V, 3 A) is a real industrial supply — keep.
- **GX16-5** locking HBOX↔cabinet connector — keep (good vibration practice).

## 4. ⚠ Change-list for the production fix (feeds the PCB + hackathon)

| Change | From → To | Why | Ref |
|---|---|---|---|
| Inner case | **ASA — keep** (adequate); optional metal / plate-mount | conduction, not material, is the lever | RCA, hardware-brief §2b |
| Internal wiring | **Dupont/hand-wire → PCB + locking connectors** | vibration intermittents | hardware-brief §4 |
| Battery path | **RESOLVED 2026-06-24: keep 18650 1S4P + LTC4040 charger** (NTC temp-qualified; MCU cuts charge when cell hot). Proto stand-in = TP4056+MT3608 | runtime needed → fix the *charging*, not the cell | `watchdog-electrical-design-state.md` |
| Fuse | **verify the 2 A blade** vs measured worst-case + inrush | client's "under-rated fuse" | RCA H5 |
| Watchdog discretes | **2N3904/IRF9540N/pull-ups → integrated load switch on PCB** | fewer parts, defined turn-on | hardware-brief §4 |
| SIM | micro-SIM buried → **front-panel SIM or MFF2 eSIM** | maintainability | hardware-brief §6.2 |
| Thermal | **v3.0: waterproof duct + Blackpill smart fan** (active managed) + conduct to plate / sunshade | a *ducted* fan removes heat without breaking IP67 | hardware-brief §2b, RCA |

## 5. Watchdog PCB v3 — Block B/E/H/I additions (2026-07-02)

> Production parts added by the 2026-07-02 capture session — **LTC4040 sized to the ~12 Ah
> 1S4P pack**; Blocks per [[03-Architecture-Hardware/watchdog-production-schematic-delta|watchdog-production-schematic-delta.md]]
> §4 (B) / §5 (E) / §5b (H) / §5c (I). Values are the sized set (RPROG → 2.42 A ≈ C/5;
> PFI trip 4.60 V; backup 4.79 V; charge = 4.00 V Li-ion via straps).
> **Fab gate: bench-validate the LTC4040 backup transition + temp-qualified charge cutoff
> before ordering boards.**

| Block | Ref | Item | Value / Package | Qty | LCSC |
|---|---|---|---|---:|---|
| B | U6 | Battery-backup manager (charger + power-path + 2.5 A boost) | **LTC4040EUFD** — QFN-24 4×5 mm, EP=GND | 1 | verify |
| B | Q7 | VIN→VSYS disconnect NFET (gate = IGATE) | AO4406A-class, 30 V ≥10 A ≤15 mΩ — SOIC-8 | 1 | verify |
| B | RS | Input current-limit sense (3.1 A) | **8 mΩ 1 %** — 1206 sense | 1 | verify |
| B | RPROG | Charge program (2.42 A ≈ C/5) | **825 Ω 1 %** — 0603 | 1 | verify |
| B | RPF1 / RPF2 | PFI divider (trip 4.60 V falling) | 287 k / 100 k, 1 % — 0603 | 1+1 | verify |
| B | RFB1 / RFB2 | Backup FB divider (4.79 V; RST −7.5 %) | 499 k / 100 k, 1 % — 0603 | 1+1 | verify |
| B | L6 | Charger/boost inductor (SW↔BAT) | **2.2 µH, Isat ≥8 A, DCR <20 mΩ** — 8040 | 1 | verify |
| B | CVIN | U6 VIN input caps | 10 µF X5R + 2.2 µF — 0805/0603 | 1+1 | verify |
| B | CVSYS | VSYS backup-transition hold-up (≥100 µF low-ESR) | 2×47 µF 1210 + 10 µF | 3 | verify |
| B | CBAT | U6 BAT cap | 22 µF X5R — 0805/1206 | 1 | verify |
| B | RNTB | Cell-NTC bias | 10 k 1 % low-drift — 0603 | 1 | verify |
| B | P4 | Battery connector (BAT+ / BAT− / NTC) | **JST-XH 3-pos** (was 2-pos) | 1 | verify |
| B | JP2 / JP3 / JP4 | Chemistry straps F2=1 / F1=0 / F0=1 → **4.00 V Li-ion** (to VSYS/GND, not 3V3) | solder jumper | 3 | — |
| E | P11 | Power-cutoff loop (MAIN5V → SYS5V; **ship with jumper plug**) | JST-XH 2-pos | 1 | verify |
| H | K1 | Modo-B fail-safe bypass relay (NC = direct uplink) | **HFD23/005-class** SPDT signal relay, 5 V coil | 1 | verify |
| H | Q6 | K1 coil low-side driver | MMBT3904 — SOT-23 | 1 | verify |
| H | R40 / R41 | Base series / base pull-down (default OFF) | 1 k / 10 k — 0603 | 1+1 | verify |
| H | D6 | Coil flyback | 1N4148 — SOD-123 | 1 | verify |
| H | P13 | Modo-B uplink (F9P_TX2 / 4G_DIN / GND) | JST-XH 3-pos | 1 | verify |
| I | R42 | NTC divider top | 10 k **1 %** — 0603 | 1 | verify |
| I | C24 | PB1 ADC settling | 100 nF — 0603 | 1 | verify |
| I | P12 | Hot-spot NTC (10 k, B≈3950 — at battery/modem) | JST-XH 2-pos | 1 | verify |
| H | K1 note | Capture uses the **Omron G6E-134P-ST-US 5 V** land pattern (`Relay_SPDT_Omron_G6E`); HFD23 alt = footprint swap | — | — | verify |

### 5b. Carrier-board additions — Block J sockets + Block K modem buck (2026-07-02 PM)

> The PROD board is now the **HBOX carrier**: all three modules on female headers (delta doc
> §5d/§5e). Board **120×100 mm**. XBee VCC = **3.3 V** (the Pro-class HP-socket spec — not 5 V),
> made by a dedicated buck on **SW_5V** so the watchdog's stack power-cycle also reboots the modem.

| Block | Ref | Item | Value / Package | Qty | LCSC |
|---|---|---|---|---:|---|
| J | MOD1 | UNO-pattern female headers for the simpleRTK2B Pro | 2.54 mm PinSocket **1×10 + 1×8 + 1×8 + 1×6** (8.5 mm stack height) | 1 set | verify |
| J | J7 / J8 | XBee socket for the 4G NTRIP Master | PinSocket **1×10, 2.00 mm**, rows 22.35 mm | 2 | verify |
| K | U7 | 3V3_MODEM buck (SW_5V → 3.33 V, ≥1.5 A pk) | **MP1584EN** — SOIC-8-EP | 1 | C107226 |
| K | L7 | Buck inductor | 10 µH ≥2 A — 8028 | 1 | verify |
| K | R60 / R61 | FB divider → 3.33 V | 100 k / **31.6 k**, 1 % — 0603 | 1+1 | verify |
| K | Dbk2 | Freewheel | SS34 — DO-214AC | 1 | C8678 |
| K | Cbst2 / Rfreq2 / Rcomp2 / Ccomp2 | BST / fsw / comp (same as Block A; ⚠ bench-tune) | 10 nF / 100 k / 40.2 k / 2.2 nF — 0603 | 4 | verify |
| K | C40 / C41 / C43 | In / out / LTE-burst bulk | 22 µF + 22 µF + **100 µF/6.3 V elco** | 3 | verify |

## Open Questions

- [ ] Confirm the **installed blade-fuse value** (2 A may be under-rated for LTE inrush).
- [x] ~~Battery decision~~ → **1S4P + LTC4040** (NTC temp-qualified charging). **Pack = ~12 Ah** (1S4P, ~3 Ah/cell; the "40 Ah" label was a mistake — corrected 2026-06-30). Sizes the LTC4040 charge current (2.5 A max ≈ C/5, gentle) + safety timer.
- [ ] Lock supplier per line (Helgen vs alternate quote) for the August batch.

## Related

- [[CLAUDE|Master Index]] · [[03-Architecture-Hardware/cabinet-electrical-bom|Cabinet BOM detail]] ·
  [[03-Architecture-Hardware/hardware-respec-and-pcb-brief|Hardware re-spec + PCB brief]] ·
  [[03-Architecture-Hardware/watchdog-schematic|Watchdog schematic]]
- **[[03-Architecture-Hardware/watchdog-electrical-design-state|Electrical design state & assumptions (CANONICAL)]]** ·
  `watchdog-protoboard-BOM-3boards.xlsx` + `watchdog-LISTA-DE-COMPRAS-ES.xlsx` (proto BOMs, 3 boards)