IoT PCB Design

J

juan1087

Design a PCB for an IoT environmental monitoring node controlled
by a Heltec WiFi LoRa 32 V3 mounted on 2.54mm female pin headers.
POWER SYSTEM:
  • DC barrel jack 5.5mm (5V input)
  • TP4056 charger module on pin headers
  • Two JST PH 2.0 connectors for 3.7V LiPo batteries in parallel,
    each with 1N5817 Schottky diode on positive line
  • AMS1117-3.3 (SOT-223) with 10uF and 100nF caps on input/output
  • 5V rail: DC jack to MQ-137 connector and Heltec 5V pin
  • 3.3V rail: AMS1117 to SHT41 connector
  • 3.7V rail: TP4056 BAT+ to Heltec 3V7 pin
SENSOR CONNECTORS (Molex 4-pin 2.54mm):
Connector 1 - SHT41:
Pin 1: GND | Pin 2: 3.3V | Pin 3: SDA->GPIO17 | Pin 4: SCL->GPIO18
Connector 2 - MQ-137:
Pin 1: GND | Pin 2: 5V | Pin 3: AOUT->GPIO2 | Pin 4: DOUT->GPIO3
PCB REQUIREMENTS:
  • Size: 70mm x 50mm
  • 4 mounting holes M3 in corners
  • Ground plane on bottom layer
  • Heltec USB-C port accessible on board edge
  • Trace width: 0.5mm signal, 1.5mm power
  • Silkscreen labels on all connectors

flux

No PCB changes were made because no ACUs are currently available for AI execution.
Remaining work:
  • Resolve power-path details, especially the AMS1117 input source and parallel-battery diode/charging topology.
  • Capture and verify the schematic, including Heltec and TP4056 header pinouts.
  • Create the 70 × 50 mm PCB, mounting holes, placement, routing, bottom ground plane, and connector silkscreen.
  • Run ERC/DRC and verify USB-C edge accessibility, 0.5 mm signal traces, and 1.5 mm power traces.
Wire up schematic
Set board size
Check pinout details
Add connectors
Review power path

Waiting for input

Sign up to send
No schematic yet

Talk to Flux to get started.