IoT Livestock Ear Tag PCB Design

flux

2:22

Gathering component details.

Analyzing the schematic.

Looking for "pin functions for WDI, ~WDO, SET0, SET1, CWD, CRST, VDD1, VDD2, GND, EP" in tps3430.pdf

Looking for "unused pin recommendations and connection guidance for SET0 SET1 WDI ~WDO CWD" in tps3430.pdf

Looking for "watchdog operation timing select pins SET0 SET1 and external capacitor CWD" in tps3430.pdf

Running multiple web searches.

Found 10 results.

Found 10 results.

Running multiple web searches.

Yes. The new watchdog still needs intentional pin decisions before I’d consider U10 fully finalized.

U10 status

Pin/groupCurrent stateNeeds intentional assignment?Why
U10 VDD1, VDD2Connected to 3V3NoSupply is already defined. TI’s product page confirms TPS3430WDRCR is a 10-pin VSON watchdog and these are supply pins.
U10 GND, EPConnected to GNDNoGrounding is already intentional.
U10 CRSTConnected to nRESETYes, but mostly doneThis is already tied into the reset path, which is the right kind of intentional connection for the watchdog reset output path. It still needs final behavioral review versus the rest of the reset strategy.
U10 WDIUnconnectedYesTI identifies TPS3430WDRCR as a window watchdog timer. A watchdog input should not be left undecided if you want real watchdog function.
U10 ~WDOUnconnectedYesThis is part of the watchdog output behavior and should be intentionally used or intentionally left unused based on the reset/fault strategy.
U10 SET0, SET1UnconnectedYesTI’s product page says the watchdog can be disabled via the SET pins and that watchdog/reset timing is programmable. These pins therefore need deliberate strap decisions.
U10 CWDUnconnectedYesTI’s product page says watchdog reset delay can be programmed by an external capacitor, so this pin needs an intentional configuration decision.
U10 NCUnconnectedLikely noThis should remain intentionally unused unless the datasheet says otherwise.
What this means
The replacement fixed the identity problem, but not the behavior definition problem.
For a real watchdog implementation, you still need to decide:
  • what signal drives U10 WDI
  • whether U10 ~WDO is used in the reset/fault path
  • how U10 SET0 and SET1 are strapped
  • whether U10 CWD gets a timing capacitor, and of what value
Bottom line
  • Identity: fixed
  • Power and ground: fixed
  • Reset connection: partially defined
  • Watchdog behavior pins: not fully defined yet
So the answer is: yes, U10 still needs additional intentional net assignments/configuration on WDI, ~WDO, SET0, SET1, and CWD.
If you want, I can next turn this into a pin-by-pin closure checklist for U10 only.
U10 closure checklist
Inspect U10 pins
Check watchdog reviews
36 days
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    Physiomx Ear Tag Rev B

    Physiomx Ear Tag Rev B thumbnail
    Production-defensible Rev B ear tag tracker using nRF9151 with separate LTE and GNSS antennas, solar-assisted LiPo charging, battery protection, SPI NOR flash, NFC, eSIM, I2C sensors, Tag-Connect SWD, grouped EVT test points, and RF/power zoning on a 40 mm x 24 mm 4-layer PCB.

    Properties

    Tag-Connect SWD plus labeled test pads for VBAT, 3V3, GND, SWDIO, SWDCLK, RESET, solar input

    Top-edge antenna keep-out reserved for LTE and GNSS antennas

    Solar-assisted single-cell LiPo with charger/power-path and stable 3.3 V rail

    40 mm x 24 mm

    40 mm x 24 mm

    ESD/TVS on solar input, charging/test pads, and tamper lines with low-capacitance protection where needed

    24 mm

    Zero ERC/DRC errors, no airwires, stable 3.3V during 350-500mA LTE bursts, accessible grouped debug/test pads, dedicated LTE/GNSS RF keep-outs, EVT-ready outputs for Seeed Fusion.

    Rectangular rounded corners

    Seeed Studio Fusion EVT proto

    Top RF zone with separate LTE and GNSS antennas and full keep-out; RF transition row with pi matching; central nRF9151 with crystals and eSIM; lower-middle sensors and NFC; bottom power path, charger, battery protection, debug and grouped test pads.

    100nF at every IC power pin, 1uF local bulk, 4.7uF main rail, 10uF near battery and charger, I2C pull-ups 4.7k, reset pull-up 10k, default GPIO bias 100k where required

    Reserved top-edge keep-out zone for LTE and GNSS antennas

    Outdoor livestock deployment

    5-10 units

    4-layer: L1 signals/components, L2 solid GND, L3 power+signals, L4 signals

    LTE-M/NB-IoT, GNSS, NFC, I2C, SPI, SWD

    45 mm x 30 mm x 12 mm

    Rev B

    Separate LTE and GNSS antennas, independent RF paths, pi matching, controlled impedance, stitching vias, keep noisy circuits away from RF

    Single-cell LiPo with solar-assisted charging and regulated 3.3V system rail

    Seeed Studio Fusion EVT, 5-10 units

    40 mm x 24 mm rounded rectangle

    Rugged outdoor animal-mounted ear tag, sealed service access, EVT 5-10 units

    4-layer: L1 signals/components, L2 solid GND, L3 power+signals, L4 signals

    40 mm

    Top edge antennas, below antennas RF matching and nRF9151, middle sensors/flash/NFC/eSIM, bottom power subsystem and battery clearance

    Pricing & Availability

    Distributor

    Qty 1

    Arrow

    $25.12–$120.45

    Digi-Key

    $6.15–$244.46

    LCSC

    $37.77–$38.00

    Mouser

    $35.68–$41.61

    TME

    $1.13

    Verical

    $6.39–$27.96

    Controls