Abstract: This article presents an introduction to a new dynamical testing and analytical system. It begins with a discussion of oversampling techniques and the theory and advantages of Σ-Δ devices for digital-to-analogue conversion(DAC), which is very suitable for dynamical testing systems. Based on Σ-Δ ADC (analogue-to-digital- converter) ADS1271, Σ-Δ DAC AIC23 and digital signal processor (DSP) TMS320C6713, the article then proposes a system with high performance of 24 bits in each of the 8 channels and many functions of digital signal processing, signal sources producing and data transmitting. The digital signal processing involves fast Fourier transform (FFT), ZoomFFT, power spectral density (PSD) and other functions. The signal sources can produce sine wave, swept wave, random wave and shock response spectrum. All the data can be transmitted to/from PC application.The system is designed for data display, secondary signal processing, signal source controlling and the interface between the users and PC, via USB2.0 devices. It can be used in vibration, shock and noise testing and control projects to replace imported hitech products.

Key words: test instrument, dynamical test and analysis, Sigma-Delta modulation, digital signal processing, synthesis waveform