Ams introduces 16-channel LED backlight controllers to improve TV picture quality and reduce power consumption

     Ams AG, the world's leading supplier of high-performance analog ics and sensors, has introduced a new 16-channel LED TV backlight controller, the AS3824, which enables local backlight adjustment of the display screen, improving TV image quality while achieving significant energy savings of 20% to 30%.

     The new backlit controller is planned for use in the latest high-definition (HD) and Ultra-High definition (UHD) TVS as well as high dynamic range (HDR) displays and monitors. Each of the AS3824's 16 channels includes a fully flexible 12-bit pulse width modulator (PWM) to ensure that the display can be backlit locally independently, and each PWM generator can be synchronized with an external synchronization signal.

     The 16-channel independent backlight function means that the intensity of the backlight in each selected area can be precisely controlled, thus matching the content of each successive frame on the display. When an area of a frame needs to be dimmed, the LED lighting in that area will be dimmed independently of the rest of the backlight, so as to ensure that the TV can restore the true image even in the deepest black area, enhancing the picture viewing experience. In contrast, the traditional full-backlight controller cannot avoid that some light will leak into the display area that should be in black, causing the black area to appear gray.

     In addition, the local backlight performance of the AS3824 enables additional system energy savings compared to conventional full-backlight controllers. The AS3824 backlight controller's precise internal 10-bit digital-to-analog converter (DAC) enables full control of accurate current (up to 5% error) via an external metal-oxide-semiconductor field-effect transistor (MOSFET) or bipolar transistor. The backlight controller supports all LED backlight topologies and there is no limit to the current or voltage passing through the LED.

     The device's 16 channels also feature a complementary 8-bit current-controlled digital-to-analog converter (DAC) that can be used to increase or decrease the local current intensity through the LED within certain frames, thereby enhancing dynamic contrast and enabling the AS3824 to support HDR displays as well as HDR TVS.

     The AS3824 also has a comprehensive set of protection support features, including hot shutdown. When the temperature exceeds 140°C, the LED short-circuit detection function will be turned on. The device can be programmed through a series of external interfaces and is linked in the form of a Daisy chain to as many AS3824 devices as required in the application.

     Bernd Krafthoefer, Marketing Manager, Power Management Division, AMS Semiconductor, said: "With the introduction of the AS3824, AMS will be the first semiconductor supplier to offer LED backlight controllers that support the latest Dolby Vision™ digital technology standard for UHD displays, helping display manufacturers achieve sharp contrast and reproduce the deepest blacks in television images."