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LED Panel Apps · October 21, 2026

How Much Power Does an LED Matrix Need? Sizing a 5 V Supply for HUB75 Panels

A single 64x32 RGB LED matrix can draw close to 8 amps at full white. Under-size the supply and you get flicker, color shifts and brownouts on the Raspberry Pi. Here's how to size it from the panel's width.

The rule

HUB75 panels are multiplexed: only a couple of rows are lit at any instant, one in the top half and one in the bottom half, and the panel scans through them fast enough to look solid. Adafruit's guidance puts each lit pixel at up to about 0.06 A at full white. So the worst case depends on how many pixels are lit at once:

max current ≈ panel width × 2 rows × 0.06 A

PanelPixels lit at onceWorst case (full white)Typical budget (half)
32x16 or 32x32643.84 A (Adafruit: "nearly 4 A")about 2 A
64x321287.68 Aabout 4 A
Two 64x32 side by side25615.36 Aabout 8 A

Adafruit suggests budgeting at least half the theoretical maximum. Real graphics, like scores on a dark background, sit far below full white. A full-screen white flash or a bright celebration animation is when you hit the ceiling.

How to choose a supply

  • 5 V only. Never a higher voltage. More amps than you need is fine; the panel only draws what it uses.
  • Size for the animations you'll actually run. If you never fill the screen with white, the typical budget works. If you do, size near the worst case, or cap brightness in software.
  • Give the Pi its own supply. Panels switching hard can drag a shared rail down and reset the Pi.
  • Use proper wire. Thin jumper wires drop voltage at 8 A. Use the panel's power leads or heavier wire, and bus bars when you chain several panels.

Work it out for your layout

The LED matrix power and size calculator takes your panel size, layout and brightness cap, and gives total resolution, worst-case and typical current, wattage and a common supply size with headroom.

Sources

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