The high-pitched noise you’re hearing from your phone charger is commonly known as “coil whine”. This noise is particularly noticeable in older televisions but is also quite common in other electrical devices. Essentially, this sound is the result of vibrations produced by the electrical current flowing through the internal components of the device. However, this could occasionally point to a malfunctioning phone charger.
What is that high-pitched noise anyway?
Human hearing can process frequencies approximately within the range of 20Hz to 20,000Hz. In some scenarios, we can detect a high-pitched noise from a phone charger when the AC power is converted to DC power.
Phone chargers work using an electromagnetic coil as a transformer rather than an inductor. This results in the conversion of lower voltage power to DC in a diode bridge rectifier. Following this, power is channeled through the capacitor before being transmitted via the power cable. Each step in this process tends to generate some level of noise.
However, if you’re hearing a high-pitched sound, it’s probably coming from the transformer. This component generates noise when electricity flows into the coil, causing the transformer to vibrate and generate a resonating frequency.
Also, switch circuits in phone chargers can produce high-frequency sounds, such as a ticking noise, which can be somewhat bothersome.
Is there a way to stop the coil whine?
While you might consider soundproofing your phone charger, it is not recommended. Soundproofing could cause the charger to overheat, which might damage the charger or even cause a fire. However, it’s important to remember that some noises are normal while others are not. Identifying the source of the noise could potentially help you eliminate it.
Inspect the charger and cable for any damage
Start by unplugging the charger from the wall outlet. Never inspect it before unplugging it to avoid the risk of electrocution. Once it’s unplugged, check the charger for any signs of damage, like a cracked casing. Damage might mean that the charger was dropped, affecting the internal components.
If there’s noticeable damage, you should replace the charger or take it to a repair shop. If the cable of the charger is damaged, you should replace that too. However, if everything seems in order, you can move to the next step.
Try a different outlet
Sometimes, the issue isn’t with the charger but with the power outlet. To test this, try connecting the charger to a different outlet. If the noise stops, your charger is likely fine. If it persists, you may need to buy a new one. Remember, the noise could be coming from the outlet, not the charger. If the outlet is buzzing, contact a local electrician immediately to prevent potential fire hazards or risks of electrocution.
Short circuit
A short circuit happens when the electrical current travels through an unintended path, and the consequences can be severe. A fire could ignite from an electrical leak caused by a short circuit. This is why it’s critical to purchase high-quality phone chargers equipped with safety features such as short circuit protection.
Faulty transformer
While transformers are often responsible for the noise, it is normal for them to produce some level of sound. However, this noise should decrease as your phone’s battery nears full charge, and should stop altogether when the battery is fully charged. If the noise doesn’t stop, it suggests a faulty transformer. Despite this issue, it is generally safe to continue using the charger.
Wireless charger
Most modern wireless chargers come with a cooling fan due to the high heat they generate. If you’re hearing a high-pitched noise from your wireless charger, it could be the fan. Switching to a wired charger can solve this issue.
More tips for avoiding the high-pitched noise
Stop using a worn-out phone charger
If your charger is a couple of years old and you hadn’t noticed any buzzing when it was new, it’s time to replace it. Components like diodes, capacitors, transformers, and rectifiers can loosen over years of use, leading to strange noises. If this applies to your charger, stop using it to prevent potential damage to your phone.
Never buy a low-quality phone charger
If you’re using a charger from an unknown brand or a counterfeit one, the high-pitched noise is probably due to the charger’s low-quality components. Buying fake or low-quality chargers not only increases the likelihood of early product failure but also poses a risk to your devices. It is therefore wise to invest in higher-quality products from trusted brands, even if they cost a bit more.
Is coil whine dangerous?
It depends. If the source of the high-pitched noise is the outlet or a short circuit, it can be extremely dangerous as it might cause a fire. However, if the source of the noise is less threatening, it’s not dangerous, although it can still be annoying!
