ESP32-C3 Smart Water Tank System PCB Design Ended

Smart Water Tank System – MAIN PCB Design

I am developing a Smart Water Tank System and I am looking for an experienced hardware engineer to design a professional PCB for manufacturing.

This is the first board of a larger system consisting of three boards. At this stage I only want to design the MAIN board.

Main requirements:

* ESP32-C3-MINI-1U microcontroller.
* USB Type-C connector used for both power and programming.
* Stable and reliable 3.3V power supply circuit suitable for continuous 24/7 operation.
* RESET button.
* BOOT button for firmware flashing and recovery.

Wireless Communication:

* HC12 communication circuit integrated directly on the PCB.
* HC12 powered from 5V.
* HC12 TX/RX connected to ESP32-C3.
* HC12 SET pin connected to ESP32 GPIO for channel configuration.
* External antenna connector for HC12.
* Good RF design and antenna placement.

WiFi:

* Use ESP32-C3-MINI-1U version with external antenna support.
* External WiFi antenna connector.
* Proper RF layout and antenna placement.

Flow Sensor:

Important:
The flow sensor is NOT part of the PCB design.

Only provide a 3-pin connector:

* 5V
* GND
* SIGNAL

The flow sensor electronics are external and no additional flow sensor circuitry is required on the PCB.

Ultrasonic Sensor:

The system uses a waterproof JSN-SR04T ultrasonic sensor.

I would like the engineer to evaluate integrating the JSN-SR04T controller board circuitry directly into the MAIN PCB if practical and reliable.

Preferred solution:
The JSN-SR04T electronics become part of the MAIN PCB and only the waterproof ultrasonic probe remains external.

The ultrasonic sensor connection must provide:

* 5V
* GND
* TRIG
* ECHO

Requirements:

* TRIG connected directly to ESP32 GPIO.
* ECHO must NOT be connected directly to ESP32.

Because ESP32-C3 uses 3.3V logic and the JSN-SR04T ECHO signal is 5V, a proper voltage divider circuit must be implemented before the ECHO signal reaches the ESP32 GPIO.

PCB Requirements:

* Compact PCB size.
* Reliable low-noise design.
* Proper power filtering.
* Proper decoupling capacitors.
* Good ground plane design.
* Stable operation in industrial environments.
* Suitable for installation inside a small enclosure mounted on top of a water tank.
* Long-term reliability is important.
* Manufacturing-friendly design.

GPIO Assignment:

GPIO assignments are not fixed.

Please select suitable GPIOs and explain the choices.

Deliverables Required:

* Schematic.
* PCB Layout.
* BOM (Bill of Materials).
* Gerber Files.
* Pick and Place Files.
* Complete source files (KiCad preferred, but other professional formats are acceptable).

Please provide:

* Estimated project cost.
* Estimated completion time.
* Examples of previous ESP32 PCB projects.
* Experience with RF layout and antenna placement.

Thank you. read less