DDS-Based 13.56MHz Sine Wave Generator for Wireless Charging System

A stable oscillator for generating a wave is one of the important parts for wireless charging system. There are many methods to establish an oscillator featuring with some advantages, one of them is using direct digital synthesizer (DDS). This paper presents the design of a sine wave generator based on an AD9850 DDS module to oscillate at the frequency of 13.56MHz. The use of AD9850 DDS module as the main component of proposed generator is motivated by the features of DDS in producing a stable wave signal and the easier in process designing. To control the output of generator, an IC controller of PIC16F628A type is integrated into the circuit of AD9850 DDS module. From experimental characterization, the realized DDS-based generator could produce a stable sine wave at the frequency of 13.56MHz with the output signal level of -20.29dBm suitable for the desired application.