A new linear voltage-to-current converter with threshold voltage compensation for analog circuits applications in polycrystalline silicon TFT process

Abstract

A new linear voltage-to-current (V-I) converter with threshold voltage compensation for analog circuits design implemented with low-temperature polycrystalline silicon thinfilm transistors (LT poly-Si TFTs) is proposed. The proposed V-I converter has been verified through simulations with Synopsys HSpice using level 62 RPI model. In order to obtain realistic simulations, parameters extraction in fabricated LT poly-Si TFTs was made. The proposed V-I converter exhibits high linearity for a wide input range (~ 2 V). Furthermore, the impact of the threshold voltage variation on the output current can be reduced from 38.5 % to 4.5 % under a biasing voltage of 6.5 V and an input voltage of 3 V.