Design of a SIBO DC-DC Converter for AMOLED Display Driving

This paper describes a Single Inductor Bipolar Outputs (SIBO) DC-DC converter for Active Matrix Organic Light Emitting Diode (AMOLED) displays. The circuit is able to generate with a single inductor both the positive and the negative voltage necessary to turn on the AMOLED pixels and does not require the addition of post-regulation techniques. The circuit works with an input battery voltage ranging from 2.4 V to 4.9 V, compliant with Li-Ion batteries, and is able to generate + 5 V and -6 V. The maximum output current delivered to the load is 0.6 A. The switching frequency is 2 MHz and the control loop has been implemented in Voltage Control Mode (VCM). The effectiveness of the single inductor based scheme has been verified at the behavioral level in Matlab-Simulink.