12V · 24V · Wide DC · Dual-Input Options

Mini-ITX Motherboards with Flexible DC Power Inputs

Choose the power input by source range, cable loss, startup load, brownout behavior, protection, connector, and continuity requirement.

  • 12V / 24VCommon industrial DC rails
  • 12–24VReleased wide-DC board direction
  • IEC 61000-4-29DC dips and interruption test reference
Check the Power Source Review My Power Requirements
Mini-ITX motherboard with flexible 12V and 24V DC power input options

Power Source Envelope

Define the Lowest and Highest Real Input Voltage Before Choosing the Board

A nominal “12V” or “24V” label is not enough. The board must remain inside its released input range during source tolerance, cable drop, battery discharge, charger operation, startup and transient events.

Source What to Record Why It Changes Board Selection
Regulated 12V Rail Minimum / nominal / maximum voltage and connector current A fixed-input board may be simplest when the source is tightly controlled
24V Control Cabinet Supply tolerance, cable length, shared loads and switching events A 12–24V or wider input stage can avoid an external DC-DC converter
Battery / UPS Charge voltage, discharge floor, switchover behavior and peak current Nominal battery voltage can hide a much wider operating envelope
Mobile / Remote Source Voltage variation, interruption profile, grounding and transient environment Requires source-specific protection and validation rather than a generic “wide DC” label

Connector vs Power Architecture

A DC Jack, Terminal Block and ATX Header Do Not Mean the Same Electrical Design

Input Style Useful When What It Does Not Prove
DC Barrel Jack Compact systems using a known external adapter Wide input range, locking retention, redundancy or surge immunity
Terminal Block Control cabinets and field wiring that need screw-clamped conductors Reverse protection, hot swap or automatic source selection
ATX / Internal Header Systems using an internal PSU or harness Acceptance of arbitrary 12V/24V sources
Two Input Connectors Projects that need two physical source paths True redundancy, OR-ing, seamless failover or hot-swap behavior

Cable Drop · Current · Power

Check the Voltage at the Motherboard, Not Only at the Power Supply

DC systems can fail during peak load even when the supply is correctly rated. Cable resistance, connector resistance and current determine how much voltage actually reaches the input stage.

Check Engineering Reference Example
Input Current I ≈ P / V before conversion losses 60 W requires about 5 A at 12V but 2.5 A at 24V
Cable Drop Vdrop = I × R 0.20 Ω loop resistance at 5 A drops 1.0 V
Delivered Voltage Vboard = Vsource − Vdrop A 12.0 V source with 1.0 V drop delivers about 11.0 V

Calculate the Complete Mini-ITX Power Budget → Size a 12V / 24V Power Supply →

Startup · Brownout · Recovery

Boot Reliability Depends on the Worst Power Event, Not the Steady-State Wattage

Inrush and Peripheral Startup

NVMe drives, USB devices, fans, radios and add-in cards can create a startup peak above steady-state consumption. Validate the complete system, not CPU TDP alone.

Undervoltage Behavior

Define whether the board should remain on, shut down cleanly, reset, or stay off when the input falls below the valid operating range.

Power Recovery

For unattended equipment, verify BIOS restore-on-AC/DC-loss behavior, watchdog interaction and whether the application returns automatically after source recovery.

Repeated Power Cycling

Test rapid off/on and marginal-voltage conditions so storage, BIOS and peripheral enumeration remain predictable after abnormal shutdowns.

Protection · EMC Immunity

Specify the Disturbance the Input Must Survive Before Specifying the Protection Parts

Power Risk Design Question Reference
Reverse Polarity What happens if field wiring is connected backwards? Board-design requirement; confirm the released protection method
Fast Switching Transients Will relay/inductive switching disturb the DC input? IEC 61000-4-4:2012 EFT/burst test reference
Surge Events What surge environment and severity must the system tolerate? IEC 61000-4-5:2014 + AMD1:2017 surge immunity reference
DC Dips / Interruptions How should the system behave during supply dropouts? IEC 61000-4-29:2026 test reference

Dual-Input Logic

Define What “Redundant Power” Must Do During Every Source State

Dual-input designs should be specified as behavior, not marketing terminology.

Source State Required Question
Input A + Input B Present Which source powers the board, or are the sources OR-ed?
Input A Fails Must the board continue without reset, or is reboot acceptable?
Inputs at Different Voltages Is reverse current blocked and is source priority defined?
Failed Source Returns Does the system switch back automatically, remain on the active source, or require control logic?

Starting Platform

Use the 12–24V Board When the Source Fits Its Released Input Window

Starting Board Use It When Confirm Before Release
12V–24V Industrial Mini-ITX Motherboard The deployed DC source remains inside the board’s released input range Connector, current, protection, startup load, peripherals, BIOS recovery, ambient range and production SKU
Custom Power Reference Platform The project needs a wider range, different connector, dual source, source-specific protection or different recovery behavior Minimum/maximum input, load profile, transient environment, failover logic, BOM and validation plan

Power Input Review

Send the Source Envelope and Load Profile

Provide minimum/nominal/maximum voltage, continuous and startup power, cable length, connector, peripherals, brownout behavior, dual-input requirement, enclosure, quantity and lifecycle target.

Submit Power Input Requirements

FAQ

Mini-ITX DC Power Input FAQ

Does a 24V supply reduce cable current compared with 12V?

For the same power, yes. A 60 W load is about 5 A at 12V and 2.5 A at 24V before conversion losses, so cable and connector voltage drop can be lower at the higher voltage.

Does having two power connectors mean the board is redundant?

No. True redundancy requires defined source selection or OR-ing, reverse-current protection, failure behavior and transfer performance. Two connectors alone do not prove those functions.

Can a 12–24V Mini-ITX board be connected directly to any battery?

No. Compare the battery’s full charge-to-discharge voltage range and transient behavior with the board’s released input range. Nominal battery voltage is not sufficient.

What should be tested for an unstable industrial DC source?

Define the actual environment first. Relevant references can include IEC 61000-4-29 for DC dips/interruptions, IEC 61000-4-4 for EFT/burst, and IEC 61000-4-5 for surge immunity.

Flexibility for Real-World Deployment Conditions

In industrial and embedded environments, power availability isn’t always standardized. That’s why our serial port platforms are designed with multiple power input options—ensuring stable operation whether you’re deploying in kiosks, factory panels, or mobile systems.