1results about How to "Improve output linearity" patented technology

The application discloses an R-2R digital-analog converter with an auxiliary calibration structure and relates to the technical field of high-precision digital-analog conversion. The converter comprises a main DAC, a calibration quantity calculation module, a compensation code generation module, an auxiliary DAC and an operational amplifier circuit. The main DAC converts a digital input into an analog current. The calibration quantity calculation module generates a 15-bit compensation code containing a 1-bit sign bit and a 14-bit data bit through a 24-bit ADC, a comparator and successive approximation logic, and only calibrates the high 12 bits of the main DAC bit by bit, and the low 4 bits do not need to be calibrated. The compensation code generation module generates a total compensation code through gating by a multiplexer and superposition by an adder. The auxiliary DAC is a 14-bit binary current type structure, and realizes bidirectional compensation in cooperation with a positive and negative reference voltage source. The application has the advantages of short calibration period, small storage consumption, no need for additional bias calibration, excellent linearity, and suitability for application in the fields of wireless communication, biological medicine and the like, and meets the application requirements of high resolution and high precision.