# M8 Humidity Probe

## Description

TRACE\-SHT45\-M8\-PROBE\-V1 preliminary production\-intent design: combined two\-board schematic, primary 4 mm sensor\-blade PCB layout, M8 carrier/mechanical documentation, factory harness, assembly/test controls, cost framework, and approval\-gate records\. Final manufacturing release files are intentionally withheld\.

## Project Details

- **Owner:** matthewallen123
- **Created:** 9/1/2026
- **Last Updated:** 9/8/2026
- **Visibility:** Public
- **Operating Voltage:** 3\.3V
- **Power Requirements:** External DC
- **Domain:** Industrial
- **Connectivity:** I2C
- **Implementation Details:** Two rigid PCBs linked by four factory\-soldered wires; 0\.5 m/100 kHz raw\-I2C qualification; 8 mm stem baseline; no final manufacturing release before approval\.
- **Compliance:** RoHS

## Key Components

### D1 — [TPD2E2U06DCKR](https://flux.ai/lcsc/tpd2e2u06dckr~6ori.md)

- License: https://creativecommons\.org/licenses/by/4\.0/
- Manufacturer Name: Texas Instruments
- Manufacturer Part Number: TPD2E2U06DCKR
- Voltage Rating: 5\.5V
- Role Details: Protects raw SDA and SCL at PCB\-A harness entry; placed before 33 ohm series resistors
- Role: Protection
- Leakage Current: 10nA
- JLCPCB Part Class: Extended Part
- Part Type: TVS
- Package or Case Code: SC\-70\-3 \(DCK\)
- Functional Group: PCB\-A Rear Interconnect and Protection
- Datasheet URL: https://www\.ti\.com/lit/ds/symlink/tpd2e2u06\.pdf?HQS=dis\-dk\-null\-digikeymode\-dsf\-pf\-null\-wwe&ts=1779250564192&ref\_url=https%253A%252F%252Fwww\.ti\.com%252Fgeneral%252Fdocs%252Fsuppproductinfo\.tsp%253FdistId%253D10%2526gotoUrl%253Dhttps%253A%252F%252Fwww\.ti\.com%252Flit%252Fgpn%252Ftpd2e2u06
- LCSC Part Number: C1855726

**Pins:**
- GND [pin 3]
- IO1 [pin 1]
- IO2 [pin 2]

### D2 — [PESD3V3U1UL,315](https://flux.ai/lcsc/pesd3v3u1ulc315~63wt.md)

- Role Details: Cathode to \+3V3 and anode to GND at PCB\-A harness entry
- LCSC Part Number: C552530
- Leakage Current: 100nA
- Datasheet URL: https://storage\.googleapis\.com/graviton\-electric\-symbols/document\_assets/lcsc/2304140030\_Nexperia\-PESD3V3U1UL\-315\_C552530\.pdf
- Manufacturer Part Number: PESD3V3U1UL,315
- Voltage Rating: 3\.3V
- Part Type: ESD Protection Devices
- Manufacturer Name: Nexperia
- Product Info Url: https://lcsc\.com/product\-detail/presales\_Nexperia\-PESD3V3U1UL\-315\_C552530\.html
- JLCPCB Part Class: Extended Part
- Functional Group: PCB\-A Rear Interconnect and Protection
- Role: Protection
- Package or Case Code: SOD\-882

**Pins:**
- A [pin 2]
- K [pin 1]

### J1 — 86 6119 1100 00004

- Connector Positions: 4
- Part Type: Connectors
- Role Details: PCB\-B male M8 interface; mating\-face pins 1=\+3V3, 2=SCL, 3=GND, 4=SDA
- Connector Type: Circular Connectors
- Manufacturer Part Number: 86 6119 1100 00004
- Manufacturer Name: Binder
- Functional Group: PCB\-B M8 Carrier
- Datasheet URL: https://www\.binder\-connector\.com/en/products/automation\-technology/m8/86\-6119\-1100\-00004\-m8\-male\-panel\-mount\-connector\-contacts\-4\-unshielded\-tht\-ip67\-ul\-front\-fastened
- Role: Coupling
- Mount: Through Hole
- Exclude from PCB: true
- Connector Gender: Male

**Pins:**
- PIN1 [pin 1]
- PIN2 [pin 2]
- PIN3 [pin 3]
- PIN4 [pin 4]

### J2 — TRACE\-4W\-HARNESS\-PADS

- Manufacturer Name: Trace Surveys
- Exclude from PCB: true
- Role Details: PCB\-B rear solder pads; brown \+3V3, white SCL, blue GND, black SDA
- Manufacturer Part Number: TRACE\-4W\-HARNESS\-PADS\-V1
- Role: Coupling
- Mount: Through Hole
- Part Type: Connectors
- Functional Group: PCB\-B M8 Carrier
- Connector Type: Terminals

**Pins:**
- \+3V3 [pin 1]
- GND [pin 3]
- SCL [pin 2]
- SDA [pin 4]

### J3 — TRACE\-4W\-HARNESS\-PADS

- Functional Group: PCB\-A Rear Interconnect and Protection
- Manufacturer Name: Trace Surveys
- Manufacturer Part Number: TRACE\-4W\-HARNESS\-PADS\-V1
- Connector Type: Terminals
- Mount: Through Hole
- Role Details: PCB\-A rear solder pads; brown \+3V3, white SCL, blue GND, black SDA
- Part Type: Connectors
- Role: Coupling

**Pins:**
- \+3V3 [pin 1]
- GND [pin 3]
- SCL [pin 2]
- SDA [pin 4]

### U1 — [SHT45\-AD1F\-R2](https://flux.ai/adrian95/sht45-ad1f-r2~q80.md)

- Functional Group: PCB\-A Sensor Tongue
- Role Details: SHT45 membrane device at exposed blade tip; official four pads only and no copper beneath package except pads
- Bus Type: I2C
- Part Type: Sensor
- Manufacturer Part Number: SHT45\-AD1F\-R2
- Role: Sensing \(Shunt\)
- License: https://creativecommons\.org/licenses/by/4\.0/
- Package or Case Code: SHT4X
- Manufacturer Name: Sensirion AG
- Operating Voltage: 3\.3V
- Datasheet URL: https://sensirion\.com/media/documents/33FD6951/67EB9032/HT\_DS\_Datasheet\_SHT4x\_5\.pdf

**Pins:**
- SCL [pin 2]
- SDA [pin 1]
- VDD [pin 3]
- VSS [pin 4]

*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://flux\.ai/matthewallen123/m8\-humidity\-probe\~hv](https://flux.ai/matthewallen123/m8-humidity-probe~hv).*

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*Generated from [https://flux\.ai/matthewallen123/m8\-humidity\-probe\~hv](https://flux.ai/matthewallen123/m8-humidity-probe~hv)*