# Power requirements in docs. Inaccurate? **URL:** \ **Category:** Uncategorized\ **Created:** [December 10, 2025, 7:52pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159 "2025-12-10T19:52:56Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![evilC](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/evilc/32/711_2.png) [@evilC](https://rpi-rgb-led-matrix.discourse.group/u/evilC)\ **Post date:** [December 10, 2025, 7:52pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/1 "2025-12-10T19:52:57Z")
The [docs](https://github.com/hzeller/rpi-rgb-led-matrix/blob/master/wiring.md#a-word-about-power) say: ## Connection You need a separate power supply for the panel. There is a connector for that separate from the logic connector, typically a big one in the center of the board. The board requires 5V (double check the polarity: what is printed on the board is correct - I once got boards with supplied cables that had red (suggesting `+`) and black (suggesting `GND`) reversed!). This power supply is used to light the LEDs; **plan for ~3.5 Ampere per 32x32 panel** * * * ## A word about power These displays suck a lot of current. At 5V, when all LEDs are on (full white), **my 32x32 LED panel draws about 3.4A**. For an outdoor panel that is very bright, that can be twice as much. * * * I am running 2x 128x64 panels, an active-3 board and a pi zero W, and my power consumption at max brightness and full white is 3.5A for the whole lot. The panels probably consume ~2.5A Looking at the git blame, seems hzeller wrote this 9 years ago - have modern panels gotten a lot better or something? Am happy to submit a PR and tone this down a bit, whilst still making it clear that you need to take this into consideration. ---
**Author:** ![board707](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@board707](https://rpi-rgb-led-matrix.discourse.group/u/board707)\ **Post date:** [December 10, 2025, 9:28pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/2 "2025-12-10T21:28:13Z")
Hi Panel consumption depends not only on size, but also on the scan, driver type, and its settings. The typical maximum consumption for a modern panel is approximately 30-40 mA per LED, but this figure can be reduced by both driver settings and your software. However, in any case, the typical maximum for two 128x64 panels is approximately 10-15 A. Your figure of 2.5 A clearly indicates that you are using no more than a quarter of the panel’s brightness. ---
**Author:** ![evilC](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/evilc/32/711_2.png) [@evilC](https://rpi-rgb-led-matrix.discourse.group/u/evilC)\ **Post date:** [December 10, 2025, 10:27pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/3 "2025-12-10T22:27:14Z")
Interesting. Not sure how it could be much brighter, at full brightness it’s clearly visible even in full direct light. Would be curious as to what I can do to make it brighter and see if it does indeed use more power - all the options I see for the demo and utils only seem to make it dimmer (with the obvious exception of course of `--led-brightness`, but that’s at max anyway) [Edit] actually, if I remove some of the options (eg –led-pwm-dither-bits=1 --led-pwm-lsb-nanoseconds=50) I can get it up to 4.8A, but still way short of 10-15A, and that’s still including ~1A of Pi usage. Also not quite getting how come one 32x32 panel will draw 3.5A, but 16x that number of LEDs would only be 10-15A ---
**Author:** ![board707](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@board707](https://rpi-rgb-led-matrix.discourse.group/u/board707)\ **Post date:** [December 10, 2025, 10:45pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/4 "2025-12-10T22:45:19Z")
> [@evilC](#): > > Also not quite getting how come one 32x32 panel will draw 3.5A, but 16x that number of LEDs would only be 10-15A Correct 🙂 On average, you can expect something around 25A for such panels. However, as I already said, it depends on the driver type and its settings. Do you know a driver model on your matrix? ---
**Author:** ![evilC](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/evilc/32/711_2.png) [@evilC](https://rpi-rgb-led-matrix.discourse.group/u/evilC)\ **Post date:** [December 10, 2025, 10:59pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/5 "2025-12-10T22:59:55Z")
Not at my desk ATM. It’s the one mentioned in [Cannot get panel to display anything](https://rpi-rgb-led-matrix.discourse.group/t/cannot-get-panel-to-display-anything/1156) ---
**Author:** ![board707](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@board707](https://rpi-rgb-led-matrix.discourse.group/u/board707)\ **Post date:** [December 10, 2025, 11:19pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/6 "2025-12-10T23:19:40Z")
As far I see, the panel uses a FM6124 driver. The datasheet for this chip is available; you can easily find it online. The very first page lists the maximum current for a single driver output: **32 mA** when powered from 5 V. ![Screenshot from 2025-12-11 02-06-56](https://global.discourse-cdn.com/free1/uploads/rpi_rgb_led_matrix/original/1X/c4f816788724e40f5e2b9a1ea5278744506cf0ad.png) Keep in mind that each color in an RGB LED powered by a separate driver, so this figure needs to be multiplied by three. This will give you about 100mA as the maximum current per pixel. You can estimate the value for a whole panel yourself, but I suspect the result will be way higher than what I just quoted. Of course, in most cases, the pixel current in the matrix is ​​limited by hardware to prevent overheating and reduce consumption. However, if we’re talking about a warning in the documentation, it’s best to stick to the maximum. ---
**Author:** ![evilC](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/evilc/32/711_2.png) [@evilC](https://rpi-rgb-led-matrix.discourse.group/u/evilC)\ **Post date:** [December 11, 2025, 2:57am UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/7 "2025-12-11T02:57:23Z")
100mA / 1000 = 0.1A per pixel 128x128 = 16,384 pixels 16,384 x 0.1A = 1,638.4A ?? 1,638.4A x 5v = 8.2 kilowatts 🤯 Surely that can’t be right. Each panel is 24x12 cm = 0.0288 m2 [Manufacturer says](https://www.aliexpress.com/item/4001321148041.html#nav-specification): Maximum power consumption(W/SQM): 880 x 0.0288 = 25.34W / 5v = **5.07A per panel** x2 panels = 10.14A Average power consumption(W/SQM): 352 x 0.0288 = 10.14W / 5v = **2.03A per panel** x2 panels = 4.06A Which seems more in line with what I am seeing, although to be fair, that appears to be the spec of the P2 / P4 variants of the panel (P2 is 128x64px, P4 is 64x32px), but seeing as the P2 is the same resolution as my P1.875 panel (Just a bit bigger), and the pixels will therefore be a bit bigger (Drawing more current?) I am guessing it is maybe even lower than those figures. Unless his estimate of 32x32 panels drawing ~3.5A is for very large panels (P8?), In which case the way it is worded is misleading (Cos he says a 16x32 will draw less - but as per that manufacturer’s spec page I linked, it does not seem to be to do with pixel count, but more to do with size) ---
**Author:** ![board707](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@board707](https://rpi-rgb-led-matrix.discourse.group/u/board707)\ **Post date:** [December 11, 2025, 6:49am UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/8 "2025-12-11T06:49:45Z")
> [@evilC](#): > > 128x128 = 16,384 pixels > > 16,384 x 0.1A = 1,638.4A ?? I see you don’t understand how the panel works. Do you know what the scan parameter means? 128 x 64 pixels never light up all at once. Your panel has a scan of 1/32, meaning only two lines of the entire panel light up at a time. ---
**Author:** ![evilC](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/evilc/32/711_2.png) [@evilC](https://rpi-rgb-led-matrix.discourse.group/u/evilC)\ **Post date:** [December 11, 2025, 8:18am UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/9 "2025-12-11T08:18:54Z")
No, I did not know that, thankyou for enlightening me 🙂 ---
**Author:** ![board707](https://avatars.discourse-cdn.com/v4/letter/b/bc79bd/32.png) [@board707](https://rpi-rgb-led-matrix.discourse.group/u/board707)\ **Post date:** [December 12, 2025, 11:55am UTC](https://rpi-rgb-led-matrix.discourse.group/t/power-requirements-in-docs-inaccurate/1159/11 "2025-12-12T11:55:49Z")
It depends. As noted above, 7A per panel is a conservative figure for bright, light-colored images that completely fill the panel. A typical average value is around 2-3A per panel. If you have low brightness and partial fill, such as single-color text with no background, you can get by with less than 1A per panel. For example, for testing purposes, I ran six 64x32 panels from a 2.5A PSU.