Hi Link HLK 2M05 5V/2W AC to DC Switch Power Supply Module

Specifications

• Model: HLK-2M05
• Module Type: Plastic-enclosed, isolated switching AC-to-DC step-down converter
• Input Voltage Range: 90V – 245V AC (50/60 Hz)
• Maximum Input Voltage: ≤ 270V AC
• Output Voltage: 5V DC (±0.2V)
• Rated Power: 2 Watts
• Output Current: 400 mA continuous
• No-Load Power Loss: < 0.1 W
• Input Surge Current: ≤ 10 A
• Enter Slow Start: ≤ 50 ms
• Isolation Voltage: 3000V AC (Input to Output isolation)
• Protections: Integrated output overload, short circuit, and over-temperature protection
• Enclosure & Pinout: High-temperature flame-retardant plastic with 4-pin through-hole PCB terminals

Applications

• Home Automation & Smart Switches: Compact power source for ESP8266/ESP32 smart relay modules fitted inside junction boxes.
• Industrial & Embedded Controllers: Powering standalone 5V microcontrollers, sensor nodes, and real-time clocks directly from 110V/230V lines.
• IoT & Appliance Retrofits: Integrating web-controlled automation inside home appliances, lamps, and HVAC controls.

Unlock New Capabilities

• Where You Started (Past Projects): If you previously used USB wall chargers wired via cut-up cables or unisolated open-board AC step-downs, you faced bulky enclosures, hazardous exposed AC traces, and erratic sensor behavior caused by noisy power rails.
• What This Unlocks (Feature Upgrade): The HLK-2M05 provides a professionally encapsulated, galvanic-isolated 5V rail directly on your circuit board. It reduces footprint by over 60%, enforces strict galvanic isolation between 230V AC and your low-voltage microcontrollers, and keeps idle power draw below 0.1W.
• Effort & Requirements: Intermediate Level. Involves direct connection to 230V AC mains electricity. Requires standard PCB soldering gear, AC terminal blocks, and basic electrical safety precautions (e.g., using inline fuses).

Package Includes:

• 1 x Hi Link HLK 2M05 5V/2W AC to DC Switch Power Supply Module

Frequently Asked Questions (FAQ)

• What is the maximum output current of the HLK-2M05?
  The module provides up to 400mA continuously at 5V DC (2W total output).
• Can the HLK-2M05 power an ESP32 or ESP8266 module?
  Yes, 400mA is sufficient for Wi-Fi microcontrollers like the ESP8266 or ESP32 when paired with an adequate decoupling capacitor.
• Does the AC input polarity matter?
  No, the two AC input pins are non-polarized, so Live and Neutral can be connected to either AC pin.
• Is the output galvanically isolated from the AC input?
  Yes, the module features up to 3000V AC optical/magnetic isolation between input and output.
• What is the idle (no-load) power consumption?
  The module draws under 0.1W when operating under no-load conditions.
• Does the HLK-2M05 require external filter capacitors?
  While it has internal filtering, adding a 10uF - 100uF electrolytic capacitor on the 5V DC output pins improves stability during sudden current spikes.
• Is an external fuse recommended on the AC line?
  Yes, a 0.5A 250V slow-blow fuse on the Live AC line is highly recommended for thermal and short-circuit safety.
• Can I connect multiple HLK-2M05 outputs in parallel for more power?
  No, switching power supplies should not be connected directly in parallel due to voltage output tolerances.
• What is the operating AC voltage range?
  It operates reliably on universal AC input voltages from 90V AC up to 245V AC (50/60Hz).
• Does the module generate significant heat during operation?
  Under normal loads (below 300mA), heat dissipation is low. At full 400mA capacity, proper ventilation is recommended.
• Can this module power 5V relay coils directly?
  Yes, a standard 5V relay coil draws roughly 70mA, which is well within the 400mA budget.
• Is this power supply waterproof?
  The plastic shell is resin-potted, providing moisture resistance, but the exposed pin terminals must be sealed if used in wet environments.
• What is the difference between HLK-PM01 and HLK-2M05?
  The HLK-PM01 provides 5V at 3W (600mA), whereas the HLK-2M05 provides 5V at 2W (400mA) in a slightly more compact footprint.
• How do I mount this power supply?
  It features standard 4-pin through-hole pins designed for direct soldering onto a custom PCB or perforated prototype board.