Design of a Frequency Division Concurrent sine wave generator for an efficient touch screen controller SoC

This paper presents an interleaved sine wave generator using an efficient memory access technique for large touch screen controllers. It concurrently applies sine waves of different frequencies. The proposed circuit improves the speed of touch detection and reduces the chip area compared with conventional analog oscillators. The range of sine wave frequencies and the gap between each of frequencies can be configured by adjusting the address calculation algorithm to fetch samples values stored in memory. Therefore it provides higher flexibility with configurable sine wave frequencies than conventional schemes. It also minimizes the memory size required to regenerate all the sine waves needed. The proposed architecture has been implemented the proposed sine wave generator in a touch screen controller with FPGA and analog front end board.