Abstract
Recently, the display panel of portable devices is normally equipped with resistor array for hand writing signal input. In newly development, photo sensitive array has been successfully embedded in the panel and the image capture by through panel has been viable. In this research, we investigate an ADC that has simple structure and could be easily implemented with multiple input array signals in different light intensity environment. With the explosive growth of wireless communication systems and portable consumer electronics, the demand for low-power low-voltage integrated circuits (ICs) is indispensable. Many of the applications nowadays utilize the digital signal processing to resolve the transmitted information. Therefore, between the received analog signal and the DSP system, an analog-to-digital interface is required. Being apart of the system, the A/D interface also needs to adhere to the low-power low-voltage constraint. In this paper, we use cyclic type ADC for subject frame which consists of sample-and-hold, 1.5bit/stage sub-ADC, 2bit Flash ADC, and Multiplying Digital-to-Analog Converter. It used Digital Error Correction Technique to avoid non-ideal circuit defects. For example: opamp gain error and comparator offset etc. This structure besides reduces non-ideal circuit defects, but also control the times of circle number to achieve the purpose of the different resolution. Although the conversion rate was slower, it could achieve low power, the small area and low cost demand. The circuit proposed above is design in a TSMC 0.35um process and verified by HSPICE program.