HU-M28 Desktop PC ATX Power Supply Breakout Transfer Module with USB and Adjustable Voltage

HU-M28 Desktop PC ATX Power Supply Breakout Transfer Module with USB and Adjustable Voltage is a multifunction ATX benchtop power supply adapter board that converts any standard 20-pin or 24-pin desktop computer ATX PSU into a versatile laboratory power station. In addition to breaking out fixed +3.3V, +5V, +12V, and -12V rails on heavy-duty binding posts, the HU-M28 integrates an adjustable 1.25V–11V step-down voltage regulator with a 3-digit LED voltmeter display and a 4-port 5V USB charging hub on a single acrylic-backed board.

Key Features:

• Built-In 1.25V–11V Adjustable Regulator & LED Voltmeter: Unlike basic passive ATX breakout boards, the HU-M28 includes an onboard LM2596/adjustable buck regulator with a rotary knob and 3-digit red LED voltmeter for variable benchtop voltages.
• Four Fixed ATX Rails (+3.3V, +5V, +12V, -12V): Heavy-duty screw/banana binding posts provide instant access to all standard computer PSU rails plus GND.
• Quad 5V USB Output Hub: Four stacked USB Type-A female sockets let you power Raspberry Pi boards, Arduino cables, and mobile devices simultaneously.
• Universal 20-Pin / 24-Pin ATX Connector: Accepts both modern 24-pin and legacy 20-pin ATX motherboard cables with an onboard latching power switch (PS_ON) and status LEDs.
• Protective Acrylic Baseplate: Includes a bottom insulating acrylic cover with standoffs to prevent benchtop short circuits.

Technical Specifications:

• Model: HU-M28 Multifunction ATX Power Supply Transfer Board
• Compatible Input Connector: 24-Pin ATX (Compatible with 20-Pin ATX PSUs)
• Fixed Output Rails: +3.3V DC, +5.0V DC, +12.0V DC, -12.0V DC, and GND
• Adjustable Output Rail (ADJ): +1.25V to +11.0V DC Continuously Variable (Up to 1.5A–2A)
• Digital Display: 3-Digit 7-Segment LED Voltmeter (Displays ADJ Output Voltage)
• USB Output Ports: 4 × USB Type-A Female Sockets (5.0V DC)

Mechanical Specifications:

• PCB & Base: Double-Sided FR-4 PCB with Protective Bottom Acrylic Insulator Plate
• Output Terminals: 6 × Color-Coded Binding Posts (+3.3V, +5V, +12V, -12V, ADJ, GND)
• Controls: Master Power Switch + Rotary Voltage Adjustment Knob

Dimensions:

• Length: 99 mm
• Width: 60 mm
• Height: 28 mm
• Weight: ~85 g

Pinout and Wiring:

• 24-Pin ATX Socket: Plug in the main 24-pin (or 20-pin) connector from a desktop PC power supply.
• Binding Posts: Connect banana plugs, spade lugs, or bare wires to +3.3V, +5V, +12V, -12V, ADJ (1.25V–11V), and GND.
• 4 × USB-A Ports: Plug in up to four 5V USB cables.
• Power Switch: Grounds the ATX green PS_ON wire to wake the PSU from standby.

Datasheet Reference:

• Standard Reference: Intel ATX12V 24-Pin Main Power Connector Specification + Integrated Step-Down Regulator

Commonly Used in:

• DIY Electronics Workbench Multi-Rail Power Supplies
• Repurposing Spare Desktop PC ATX Power Supplies
• Op-Amp Dual-Supply (+12V / -12V) & Logic (+5V / +3.3V) Testing
• Multi-Device 5V USB Development Board Power Hubs

Applications:

• Transforms a retired 300W–500W desktop PC power supply into a high-current laboratory bench supply with fixed +3.3V/+5V/±12V rails plus a variable 1.25V–11V output.
• Powers dual-supply analog operational amplifiers using the +12V, GND, and -12V binding posts while powering digital logic on +5V/+3.3V.
• Charges and powers up to four 5V USB development boards from the integrated quad-USB port bank.

Equivalent Models:

• XH-M229 Desktop PC ATX Power Supply Transfer Module: Fused 4-rail (+3.3V, +5V, +12V, -12V) ATX breakout board without the adjustable voltmeter stage.
• ZK-4KX CNC DC-DC Buck-Boost Converter CC CV 0.5-30V 4A Power Module: Add-on CC/CV buck-boost module to pair with the +12V ATX rail.

Package Includes:

• 1 × HU-M28 Desktop PC ATX Power Supply Breakout Transfer Module with USB and Adjustable Voltage