Anas A. Hamoui Mohammad Sukhon Franco Maloberti Digitally-enhanced 2nd-order DeltaSigma modulator with unity-gain signal transfer function. 1664-1667 2008 ISCAS http://dx.doi.org/10.1109/ISCAS.2008.4541755 conf/iscas/2008 db/conf/iscas/iscas2008.html#HamouiSM08