Embedded System for Supply Voltage Converter of Organic Light-Emitting Diode

Abstract

The work is dealing with the problem of developing an embedded system for supply voltage converter of Organic Light-Emitting Diode (OLED) with advanced built-in ability to measure the volt-ampere (I – V) characteristics of structures directly during their operation. This feature is crucial in the development of a new generation of intelligent OLED controllers, which in relation to known solutions, are characterized by reduced power consumption and increased speed of periodic or continuous measurement of the I – V characteristics of OLED structures. On the basis of such measurement the drift of characteristics of OLED structures in the course of their operation is carried out, and therefore, the possibility of operative correction of their power modes is provided. The measurement of I – V characteristics of OLED structures is performed on the transients of voltage generation in the boost circuits of the drivers. To meet the requirements for such measurements, the parameters of the transient pulses must meet certain criteria. The pulse amplitude should be sufficient to scan the I – V characteristics of OLED structures in the whole range of their possible operation, and the shape and rise time should be optimal from the point of view of further detection of these I – V patterns, in particular, regarding their drift in temperature modulation or OLED structure degradation. In a number of tasks scanning and measurement of I – V characteristics should be fast enough to prevent heating, but acceptable for high-precision analog-to-digital conversion. The parameters of the pulses provide the ability to measure the thermal parameters of thermal resistance and its dependence on the duration of heating. The controller is implemented on the basis of programmable systems on the chip, namely on the PSoC 5LP.