How to turn off PWM on Xiaomi: screen settings and DC Dimming

Many Xiaomi, Redmi and POCO smartphone owners experience rapid eye fatigue, headache or discomfort when using the device at night. The main cause of these discomforts is often a screen brightness control technology known as PWM. Unlike constant glow, brightness changes due to the very rapid blinking of pixels, which is invisible to the eye but is fixed by the brain.

Modern. AMOLED-The matrices that are commonly installed in mid- and flagship-segment devices are particularly susceptible to this effect at low brightness levels. Fortunately, Xiaomi engineers have implemented software solutions to minimize the impact, but they are often hidden from the average user. In this article, we will discuss how to turn off PWM on Xiaomi by activating the mode. DC Dimming or using other available methods.

It's important to understand that not all PWM hardware is completely disabled, because it depends on the physical structure of the array. However, software brightness interpolation implemented through DC Dimming allows you to significantly reduce the pulsation frequency, making it safer for vision. We'll look at both standard settings and hidden engineering menus.

The principle of PWM and the impact of vision

Latitudinal Pulse Modulation (PWM) technology is used to control the brightness of LEDs in displays. OLED-The pixels can’t just “dilute” their glow like they do. LCD-The system makes them turn on and off at a high frequency. The lower the brightness, the longer the pixel is off.

For some users, the 240Hz or even 480Hz frequency that is typical of many Xiaomi models is not enough. The brain perceives these fluctuations of light, which leads to straining of the eye muscles. This is especially noticeable on the Xiaomi Mi 11, Redmi Note 10 Pro or POCO F3, where low-pWM arrays are used.

⚠️ Warning: If you feel a pain in your eyes or headache after 30 minutes of using your smartphone at low brightness, your body is sensitive to screen pulsation and you need to look for ways to eliminate it.

There are two main types of adjustment: classic PWM and DC Dimming. In the second case, the brightness changes by changing the voltage applied to the pixel, which eliminates blinking. However, this method has its drawbacks, which we will discuss later.

What is DC Dimming and How Does it Work?

DC Dimming is a software algorithm that emulates DC, and the system takes the original image and, before it is fed to the screen, applies a gamma-ray correction to it, changing the voltage on the pixels instead of turning them on and off frequently, which allows the flicker effect to be turned off at the software level.

Activating this feature doesn’t change the physical structure of the matrix, but it makes the display controller work in a different mode. On Xiaomi smartphones, this option is often hidden in the Developer Menu or in a special section of the display settings that you need to activate through a hidden menu.

It's worth noting that DC Dimming can be a little color shift or low-brightness "noise" -- a price for not flickering -- and for many users, this trade-off is the only way to read comfortably from your phone at night.

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Before turning on DC Dimming, take a screenshot of the screen with a white background at low brightness to compare the color reproduction before and after activation of the function.

How to enable DC Dimming through a hidden menu

In the shell. MIUI HyperOS function DC Dimming is often hidden from ordinary users, and to activate it, you need to use a special code in the Phone application or find a hidden partition in the settings. AMOLED-screen.

The first and most reliable way is to use engineering code. Open the Phone app and type ##6484##. This will open the CIT (Customer Interface Test) menu. However, newer versions of MIUI may not open the full menu but run tests immediately, so try looking for the word "DC" or "Dimming" in your settings.

If the search doesn’t help, use the second method through the hidden display developer menu:

• 📱 Go to Settings. → The phone.
• 👆 Find the item Version. MIUI And press it quickly. 7-10 Once you have the words “You became a developer".
• ⚙️ Return to the main settings menu, go to additional → For developers.
• 🔍 Scroll down to the section related to hardware acceleration or display and find the switch. DC Dimming.

In some cases (e.g., global firmware versions), the item may be called "Anti-flicker mode" or "Anti-flicker mode." Once the slider is turned on, the screen may blink, which is the normal system response to a change in the matrix mode.

Alternative Methods: Reading Mode and Dark Theme

If your standard DC Dimming model doesn't work or doesn't work, you can use software crutches that also reduce eye strain, although they don't completely remove PWM, and one of those methods is Reading Mode.

This mode converts the screen to a monochrome format and often changes the backlight algorithm to make the glow softer. To activate it, go to Settings → Screen → Reading Mode. Here you can adjust the schedule and intensity of the effect.

Also effective is the use of a dark theme in combination with minimal brightness. AMOLED-In the screens, black means the pixel is off. If the interface is black, there's nothing to flicker about. But if you use light interface elements, PWM comes back into play.

⚠️ Warning: Don’t use third-party apps from the Play Market that promise to turn off PWM by black filtering. They simply darken the image programmatically, making the backlight run at a minimum where PWM is most pronounced, which only makes things worse.

Another option is to use Night Light or Blue Filter widgets, which change color temperature, and although this does not affect the frequency of the pulsation, the warm spectrum of light is less irritating to the retina at night.

Comparison of modes: PWM vs DC Dimming

Understanding the difference between the two screen modes will help you choose the best option to use. Below is a table comparing the key characteristics of both methods.

As you can see from the table, DC Dimming benefits in terms of health safety, but loses in color rendering accuracy, which is why graphics professionals are advised to turn off this feature when editing photos, but turn it on for reading and social networks.

Checking for flickering with a camera

To make sure you’ve turned off PWM on Xiaomi, you can do a simple visual test, and you’ll need a second smartphone with a good camera that can shoot in Manual mode with short shutter speed.

Set your camera to the second phone: set shutter speed to 1/1000 or 1/2000 of a second. Point your lens at your Xiaomi screen, minimize the brightness. If you see horizontal bands running across the screen, that's PWM.

Once you turn on DC Dimming, repeat the procedure, the bands should disappear or become barely noticeable, and the image on the screen of the second phone will become more uniform, which will confirm that the pulse rate has been reduced to a safe level.

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The lack of stripes on the screen when shooting with short exposure is the main visual sign that DC Dimming is working correctly.

Frequently Asked Questions (FAQ)