Organic light-emitting diode (oled) displays are becoming more common, most prominent among products such as mobile phones, media players and small entry-level tvs. Unlike standard lcds, oled pixels are driven by a current source. To understand how and why the oled power supply affects the quality of the display, you must first understand the oled display technology and power supply requirements. This paper describes the latest oled display technology and explores major power supply requirements and solutions, as well as the innovative power supply architecture proposed for oled power supply requirements.
Backplane technology creates a soft-display high-resolution color active-matrix organic light-emitting diode (amoled) display that uses an active-matrix backplane that switches on and off each pixel. The liquid crystal (lc) display amorphous silicon process is ripe for supplying low-cost active matrix backplanes and for use in oled.
Many companies are developing an organic thin-film transistor (otft) backplane process for soft displays, which can also be used in oled displays to deliver full-color soft displays. Both standard and soft oled require the same power supply and drive technology. To understand oled's technology, functionality, and interaction with power supply, you need to dissect the technology itself. The oled display is an autoluminescent display technology that does not require any backlighting at all. The material used by oled is organic for chemical structures. oled technology requires current control driving method oled has quite similar electrical properties to the standard light emitting diode (led), and brightness depends on the led current. to turn on and off oled and control the oled current, use the control circuit of the thin film transistor (tft).
As with any battery-powered device, the advanced energy-saving mode can achieve the highest efficiency, and only if the converter operates with the highest efficiency in the overall load current range can it achieve a longer battery standby time, which is particularly important for the oled display. The oled displays consume the largest amount of power when they are all white, and the current is relatively small for any other color, because only white requires all the red, green and blue pixels to be fully bright. For example, a 2.7-inch display requires an 80 ma current to present an all-white image, but only a 5 ma current to show other icons or graphics. therefore, the oled power supply needs to reach high converter efficiency for all load currents.
To achieve such efficiency, advanced energy-saving mode technology is needed to reduce the load current to reduce the converter switching frequency. since this is done through the voltage control oscillator (vco), it is possible to minimize possible emi problems and to minimize the minimum switching frequency beyond the audio range of the general 40khz, which avoids noise from the ceramic input or output capacitance. This is particularly important when using such devices in mobile applications and can simplify the design process.