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PCB Articles

This section contains the hardware architecture documentation for each PCB assembly in the EverTag Connectivity Module family. The 232200 Base Std is the main reference document; variant PCBs describe only the differences from the base.

PCB Comparison

PCB Name MCU Module WiFi Battery NFC PIR LTE Ext Status
232200 Base Std PAN611 (nRF54L15) - - PCB antenna - - Active
232201 Base Bat PAN611 (nRF54L15) - LiFePO4 PCB antenna - - Active
232202 Base WIFI PAN611 (nRF54L15) ESP32-C5 - PCB antenna - - Active
232203 Base Bat+WIFI PAN611 (nRF54L15) ESP32-C5 LiFePO4 PCB antenna - - Active
232204 Base Bat+Radar PAN611 (nRF54L15) - LiFePO4 PCB antenna Yes - Not in first iteration
232210 Ext LTE EU - - - - - SIM7672E Not in first iteration
232211 Ext LTE US - - - - - SIM7672NA Not in first iteration

Document Structure

The base PCB (232200) document contains all chapters in full detail:

  1. Overview
  2. Block Diagram
  3. Schematics
  4. Pin-Out (incl. GPIO assignments for firmware)
  5. Component Selection
  6. PCB Design Notes
  7. Test Points & Validation
  8. Revision History

Variant PCBs (232201-232203) document only the delta from the base. For shared functionality, they reference the 232200 documentation.

Future PCBs (232204, 232210, 232211) are fully specified but are not included in the first PCB iteration. The enclosure and base platform are prepared for these extensions.

graph TD
    Base["232200 Base Std - Full Document"]
    Bat["232201 Base Bat - Battery delta"]
    Wifi["232202 Base WIFI - WiFi delta"]
    BatWifi["232203 Base Bat+WIFI - Combined delta"]
    BatRadar["232204 Base Bat+Radar - Anchor with presence"]
    LteEu["232210 Ext LTE EU - Future"]
    LteUs["232211 Ext LTE US - Future"]

    Base --> Bat
    Base --> Wifi
    Base --> BatWifi
    Base --> BatRadar
    BatWifi --> LteEu
    BatWifi --> LteUs

Board Variant Detection (HW Design)

All assembly variants use a resistor divider on P1.07 (V_SAMPLE) for firmware to detect the board type at runtime. Populate R_bottom per assembly variant — R_top is fixed at 100k (1%).

Assembly Variant R_top R_bottom Notes
232200 Base Std 100k 16.5k
232201 Base Bat 100k 33k
232202 Base WiFi 100k 49.9k
232203 Base Bat+WiFi 100k 66.5k
232204 Base Bat+Radar 100k 82.5k

Extension boards (via P1.12 EXT_DETECT):

Extension R_top R_bottom
232210 Ext LTE EU 100k 16.5k
232211 Ext LTE US 100k 33k

Circuit & Tolerance

VCC → R_top (100k 1%) → P1.07 (ADC) → R_bottom (variant) → GND. Use 1% resistors. Full scheme, ADC windows, and tolerance analysis: Firmware Compatibility — Board Variant Detection.

Shared Enclosure

EverTag Connectivity Module in enclosure -- front view and AE-AE cross-section

All connectivity module variants share the same enclosure (article 232506):

Parameter Value
Material PC+ABS matte
Flame rating UL94 V0
Color White matte
Prepared features PIR window region (not populated), internal volume for extension board (LTE modem + on-board chip antenna)

PCB Placement

The PCB is not centered inside the enclosure. LED and button placement on the PCB must account for the off-center position to align with the enclosure window and access points. Complete enclosure drawings are provided separately to the PCB designer (outside the scope of this documentation).