Wx-dc12003 Schematic -

Understanding the internal design of this module helps prevent catastrophic failures when interfacing mains power directly with sensitive microcontrollers like the ESP32 or Arduino. Core Specifications Overview

Vref = 1.25V, R1=3.3k, R2=1k → Vout = 1.25*(1+3.3/1) = 1.25*4.3 = 5.375V (within 5% tolerance). wx-dc12003 schematic

If you have the actual PCB, here is how to map it: Understanding the internal design of this module helps

The transformer provides galvanically isolated energy transfer between the high-voltage primary side and the low-voltage secondary side. It functions at a high switching frequency, enabling its incredibly small footprint. It functions at a high switching frequency, enabling

: Often an integrated IC that manages the power MOSFET to maintain a stable output regardless of input fluctuations.

: Approximately 80% with a no-load power consumption of less than 0.05W.

A Schottky diode and filter capacitor smooth the output. Some versions include an optocoupler for voltage feedback to keep the 5V steady. Design Variations