Arcade machines, from classic cabinets to modern fighting games, rely on specialized power supplies to convert wall electricity into the precise voltages needed for their components. The most common requirements center around standardized outputs and physical form factors.

The majority of classic arcade machines operate on a switching power supply that converts AC wall current (100-120V in North America, 220-240V elsewhere) into three key DC outputs: +5V, +12V, and sometimes -5V. The +5V rail is absolutely critical as it powers the game's logic board, CPU, and RAM. The +12V rail typically drives audio amplification circuits and cooling fans, while the -5V was historically used for certain sound chips in older games but is less common today.

Amperage requirements vary significantly by the machine's complexity. A simple classic game like Pac-Man might only need 3-5 amps on the +5V line, while a larger 90s fighting game with more RAM and processing power could require 10-12 amps or more. It's crucial to match or exceed the original power supply's amperage rating when replacing a unit.

Physically, most arcade power supplies follow the JAMMA (Japan Amusement Machine and Marketing Association) standard, which specifies a particular board size and screw placement for mounting. They feature standardized terminal blocks or Molex-style connectors for output. The input is typically a standard IEC 3-prong computer power cable.

Modern replacement power supplies often include adjustable potentiometers for fine-tuning the +5V output, as voltage that is too low can cause game glitches and resets, while voltage that is too high can permanently damage sensitive PCBs. When maintaining or restoring arcade cabinets, using a multimeter to verify these voltages at the game board itself is considered essential practice.