38.2: Highly Efficient P‐Type Only Cross‐Coupled DC‐DC Converter Using Low Temperature Poly‐Si (LTPS) TFTs for Mobile Display Applications

This paper proposes a novel highly efficient p‐type only cross‐coupled DC‐DC converter using low temperature poly‐Si (LTPS) TFTs for mobile display applications. for fast switching operation at the gate node of driving TFT, the proposed p‐type only DC‐DC converter includes diode connected TFTs to initialize the driving TFT and a capacitive coupled clock input. The proposed DC‐DC converter was fabricated in p‐type only LTPS process. The measured output voltage is 8.8V in voltage up‐converting operation while consuming a load current of 250μA. Its power efficiency is 79.6%. Compared to the previously reported Dickson's charge pump, power efficiency is increased to 202.0% and integrated circuit area is reduced to 63.3%.