A 120V high voltage DAC array for a tunable antenna in communication system

This paper presents a integrated high voltage digital-to-analog converter array, which is designed by using a 0.35μm high voltage CMOS technology(AMS H35), and can be applied in high voltage applications up to 120V. The DAC array has 16 high voltage DACs controlled by a digital controller on chip. To fulfil the requirement of communication system with reconfigurable antenna implemented using materials which have voltage dependent capacitance, the DACs are designed to have 8 bits of resolution. In order to improve the accuracy and decrease the required area, each independent DAC is implemented by a low voltage DAC and a high voltage amplifier for boosting the controllable output voltage. Since the current consumption from the high voltage power supply is only 1.28mA, it is possible to be powered by a charge pump which generates high voltage power supply from a battery. The proposed HV DAC array can drive up to 16 individual channels of antenna array with different voltages from 0V to 120V. It will greatly reduce the complexity and cost of mobile applications required high voltage. The feasibility is proved by post-simulation result.