High Precision D / A Data Conversion Chip Testing Methods And Improvements

The major functional parameters of a digital-to-analog converter (DAC) are composed of static parameters such as DNL and INL, as well as dynamic parameters such as SNR, THD, SINAD, SFDR, etc.There are new challenges for device test as data converters continue to improve dynamic range performance while providing faster data rates.A common challenge in Digital-to-Analog Converter(DAC) testing is to identify an AC capture instrument with the necessary analog bandwidth, dynamic range,and noise density to test the device properly. Otherwise, accuracy is no longer guaranteed since the measurement is about the tester itself.This paper proposes an improved methodology for static and dynamic tests on high resolution digital to analog converter device. For Static parameters,introduction will be given on using DC30 differential meters on multiple sites with precision voltage sourced as pedestal base, followed by specific calibration techniques to improve test accuracy. For dynamic parameters,a notch filter, multi-stage amplifier technique will be described that can improve the wide bandwidth AC capture instrument dynamic range.A technical overview of the technique,recommendations on DIB design, as well as measured results will also be presented.Improvements on testing methodology will cover peripheral circuit design, test program coding and debugging based on automated testing equipment (ATE),as well as correlation with traditional methodology and device spec,as accuracy and efficiency are always two important factors being cared most in mixed signal test.