ESP32-C3 RS232 Bridge PCB

Job ID: 40075052

Budget: $250 – $750 USD

I need an experienced electronics engineer to design a compact, production-ready "Man-in-the-Middle" carrier board for the ESP32-C3-MINI-1-N4 module.

The Goal: The board sits in-line between a Dometic Air Conditioner and its control unit. It must actively intercept RS232 traffic (modify/inject data) and control an external IR transmitter.

Timeline:

First-pass files needed within 7 days.

I need a partner who is collaborative and can discuss design trade-offs (e.g. pass-through routing).

Technical Requirements:

Core: Built around the ESP32-C3-MINI-1-N4 (SMD Module).

Power: 12V DC Automotive Input (via JST header).

CRITICAL: Must use a robust Buck Converter (Step-down to 3.3V) for thermal stability. LDOs are NOT acceptable for the main drop.

Include Reverse Polarity & Transient protection.

Connectivity (The Bridge):

Two 7-Pin JST XH Male Headers (See attached photo of port).

Wiring: Direct pass-through for Power/GND. Data lines (TX/RX) must be intercepted and routed to the ESP32 via a MAX3232 transceiver.

Infrared:

1x 3.5mm Audio Jack (Female) to drive an external IR Emitter.

Driven by a simple transistor/MOSFET circuit from a GPIO.

Programming:

No USB connector.

Design a "Bed of Nails" footprint (Test points/pads) for VCC, GND, TX, RX, IO9, EN to allow factory flashing via Pogo pins.

Deliverables:

Source Files: KiCad schematic and layout.

Fabrication Files: Gerber X2, Drill files, and Pick-and-Place (CPL) file.

BOM: Excel BOM with Manufacturer Part Numbers verified in-stock at DigiKey, Mouser, or LCSC.

**Fabrication Files: Must include JLCPCB-formatted BOM and CPL (Centroid) files with 'LCSC Part #' column populated and component rotation pre-verified for JLCPCB assembly.

Readme: Brief notes on assembly or jumper settings.

Acceptance Criteria:

ERC/DRC Clean: Design must pass standard rule checks.

Nets Labelled: Schematic must be readable and logically organized.

Connector Verification: You must help verify the JST connector Part Number against the attached photos to ensure it fits the existing cable.

To Apply: Start your bid with the word "GLAMPING" to confirm you read the requirements. Please mention if you have experience with automotive power protection.
Related categories: Electronics PCB Layout Circuit Design