中文摘要：

文中针对模拟电路实现ΣΔ调制对输入信号幅度存在限制的问题,设计实现了基于FPGA数据扩展方式的二阶ΣΔ调制器。该调制器能够对满幅信号进行正确调制,且输出波形可通过简单的无源滤波器实现量化噪声的滤除及信号的解调。相对于模拟电路,FPGA实现通过内部寄存器数据位的有效扩展,防止中间过程数据溢出造成的调制错误,保证电路的稳定性。相应结论均通过仿真模拟及硬件实现证明。

英文摘要：

In view of the problem that ΣΔ modulator implemented in analog circuits is limited by the amplitude of input signals,this paper designed a second-order ΣΔ modulator based on a Field Programmable Gate Array（ FPGA） data expansion method. The modulator can accurately modulate full-scale signals; in addition,for the waveform output,a simple passive filter can be used to realize the filtering of quantizing noise and the demodulation of signal. Compared with the simulated circuit,the FPGA can realize the effective expansion via the data bits of inner memory,prevent the wrong modulation caused by the overflow of the intermediate process data,so as to guarantee the stability of circuit. The corresponding conclusions are verified by simulation and hardware implementation.