What is a picoPSU?

What Is a picoPSU?

A picoPSU (short for pico Power Supply Unit) is a miniature DC-to-DC power converter designed specifically for space-constrained PC builds, especially those based on Mini-ITX motherboards. Unlike conventional ATX power supplies that convert AC wall power directly to DC, the picoPSU relies on an external AC-to-DC power brick to provide regulated 12V DC input, which it then distributes as required to the system components.

How Does a picoPSU Work?

A picoPSU operates as a DC-to-DC power converter, efficiently regulating power for compact and low-power PC systems. Unlike standard ATX power supplies, which draw AC power directly from the wall and convert it internally, a picoPSU works in conjunction with an external AC-to-DC power adapter, typically delivering 12V DC input to the system.

Power Conversion Process:

1. External Power Adapter

   • Converts AC (110V–240V) to 12V or 19V DC

   • Acts as the main source of input power

2. picoPSU Module

   • Receives DC input and converts it into multiple DC voltages:

     • +12V for CPU fans, GPUs, or drives

     • +5V for SSDs, HDDs, USB devices

     • +3.3V for motherboard and RAM

   • Powers components through the 24-pin ATX connector and additional output leads (e.g., SATA, Molex)

Why DC-to-DC Matters

The DC-to-DC regulation used in a picoPSU improves power efficiency by eliminating the AC-to-DC conversion stage inside the case. This not only reduces heat but also allows:

• Fanless operation

• Tighter voltage regulation

• Higher overall system efficiency

System Compatibility

A picoPSU connects directly to:

• Mini-ITX or microATX motherboard (via 24-pin header)

• Peripheral devices (via SATA, Molex, and CPU 4-pin connectors)
  
  

Main Use Cases and Applications

The picoPSU is purpose-built for environments where space, silence, and energy efficiency are critical. Its compact size, low heat output, and fanless design make it an ideal power solution across a wide range of computing applications, from home entertainment to industrial automation.

1. Mini-ITX and Small Form Factor (SFF) PCs

One of the most popular use cases for the picoPSU is in Mini-ITX builds, where internal space is extremely limited. Traditional ATX power supplies are too bulky for these compact cases. A picoPSU plugs directly into the motherboard, freeing up space and reducing cable clutter. It enables:

• Low-profile system design

• Improved airflow

• Silent operation

2. Home Theater PCs (HTPCs)

For media enthusiasts building HTPCs for living room setups, noise levels and heat dissipation are key concerns. The picoPSU offers:

• Zero noise (fanless)

• Lower power consumption, often under 100W

• Compatibility with external power bricks, making it easy to hide cables

It’s perfect for media streaming, Plex servers, or Kodi-based setups.

3. Industrial and Embedded Systems

In industrial environments, reliability and space efficiency are vital. Many embedded computing platforms, such as factory controllers or kiosks, benefit from picoPSUs because of:

• Wide DC input ranges (6V–24V)

• Shock and vibration tolerance

• Long-life fanless design

These features make picoPSUs a go-to for automation, IoT edge devices, and digital signage.

4. Automotive and Mobile Computing

For in-vehicle PCs or car-based computing, the picoPSU supports direct 12V input, matching typical car battery voltage. It allows:

• Powering compact systems without an inverter

• Energy-efficient PC use in fleet management, navigation, or vehicle diagnostics

5. Fanless Workstations and Silent Builds

Professionals who require silent environments—such as audio engineers or content creators—use picoPSUs to eliminate fan noise altogether. Combined with passive cooling and SSD storage, they form the core of zero-noise desktop systems.

Advantages of Using a picoPSU

Limitations and Considerations