Hitt Chwang & Gaines, P.C.
4th-order sigma-delta modulator with leapfrog topology
 The invention relates to a high performance and absolute stable 4th-order sigma-delta modulator with leapfrog topology which contains the following key components: (a) four integrators for integrating the difference signal between the input and reconstruct signal; (b) three add/subtract adders for adding or subtracting analog signal; (c) three loop coefficient control members for controlling the performance and stability of the modulator, (d) an analog-to-digital converter (A/D converter) for quantizing the output signals of the fourth integrator to digital codes, and (e) a digital-to-analog converter (D/A converter) for converting the digital codes to analog signals. 
National Science Council
H H
H03M H03M
inventional additional
Chun-Hsien Tai-Haur Wen-Chyi Jhy-Rong Wen-Bin
Su Kuo Wang Chen Lin