Arbitrary waveform generator based on PXIe bus

Abstract

The invention relates to the field of signal generator, and specifically relates to an arbitrary waveform generator based on a PXIe bus. The generator comprises a waveform generation part and a waveform conditioning part. The waveform generation part comprises an FPGA and a crystal oscillator. The waveform conditioning part comprises a 16-bit DAC, an operational amplifier, an SPI program control amplifier, a filter circuit, an SPI program control DAC, a differential operational amplifier, and a subtracter. The generator employs the PXIe bus as a channel which is used by an upper computer for transmitting waveform data. The FPGA continuously process the waveform data transmitted by the upper computer in a waveform generation process, so as to guarantee the integrity of high-frequency signal quality. In a waveform conditioning process, the generator respectively employs a Bessel filter and an elliptic filter according to the frequency characteristics of signals and the difference of anti-noise capabilities, and meets the filtering requirements of different types of signals. For a signal with the amplitude being less than 50mV, a small signal processing branch circuit is designed, thereby guaranteeing that a signal with a small amplitude value cannot be flooded by noise. The generator employs a mode of internal and external synchronization adjustment for signal amplitude and bias, and guarantees the accuracy of a signal.

Description

technical field [0001] The invention relates to the field of signal generators, in particular to an arbitrary waveform generator based on a PXIe bus. Background technique [0002] In the process of electronic system design, the waveform generator is indispensable in the process of circuit hardware debugging and testing. It is often necessary to use the waveform generator to generate a test waveform to observe whether the circuit is working normally. Therefore, the growing demand puts forward higher requirements for the portability and functional integrity of the waveform generator. [0003] Waveform generators can generally be divided into benchtop waveform generators and modular waveform generators. Benchtop waveform generators are single-function, bulky and expensive. The modular waveform generator has instrument standards, and has certain advantages in terms of software and hardware expansion and cost. However, the modular waveform generator is limited by the size of t...

AI Technical Summary

Problems solved by technology

However, the modular waveform generator is limited by the size of the board and the onboard storage space is limited. The direct impact is that the quality of the high frequency signal is not perfect.

In addition, due to the large noise floor of the modular waveform generator, the direct consequence is that the small-amplitude signal is superimposed with more noise, making its waveform characteristics not obvious

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