What Is a Screen Inverter?
A screen inverter is a small circuit board in a laptop computer that passes a power current from the body to the liquid crystal display (LCD) screen. The screen inverter works by turning a direct current (DC) from the motherboard into an alternating current (AC). The AC current then sparks the backlight, causing the computer's images to appear on the screen. It is also known as a backlight inverter or an LCD inverter, among other names.
The primary function of the screen inverter is to power the laptop LCD. As laptop technology has improved, the inverter boards have become smaller and of better quality. The inverter is located just below the LCD display in most laptops, and can usually be accessed easily when the plastic frame is removed from around the screen. It is typically connected on one end to the the video cable and on the other to the backlight. In addition to powering the screen, the inverter also creates a better screen resolution and can give users more control over their display options.
Even though a screen inverter performs a seemingly simple task in laptop computers, it can also be one of the most common to fail. When this occurs, it can sometimes be difficult to determine if the backlight is burned out or if the screen inverter has gone bad. The symptoms of each are very similar and both can display a dark or briefly lighted screen with some or no images.
Most times when a screen inverter has gone bad, the screen will appear to be lit, but the light will be very dim and the images will be very difficult to see. When a laptop has a faulty screen inverter, the LCD may display only very faint images, or the laptop could appear to be powering up, but the screen remains dark. Often, a bad inverter can be attributed to faulty circuits or bad conductor coils.
When repairing or replacing a defective screen inverter, there are multiple resources available, including websites, computer services, and qualified technicians. It may be helpful to also check the warranty information on the computer prior to making any repairs or replacements. If the laptop still has a warranty, the manufacturer will usually take care of the repair at no cost and the warranty will likely remain intact.
If there is no current warranty information on the laptop, replacing the inverter is typically inexpensive and can be done quickly. There are multiple websites that detail the step-by-step process of replacing the inverter board. It can also be beneficial to check the video card in the laptop with an external monitor to make sure it isn't the source of the problem; this can save quite a few headaches if the problem is not something a user can repair.
Written by Derek Schauland
