The　design　of　a　third-order　single-bit　discrete-time　Sigma　Delta　modulator　for　low-power　energy　meter　application　is　presented.　The　modulator　employs　an　input　feed-forward　topology　in　order　to　reduce　internal　signal　swings,　thus　relaxes　the　linearity　and　slew　rate　requirements　on　amplifiers.　A　partially　switched　amplifier　is　utilized　in　the　first　integrators　for　low-power　consumption.　The　circuits,　simulated　at　the　transistor　level　using　a　0.13-mu　m　CMOS　process,　obtains　a　peak　SNDR　of　99dB　over　an　input　signal　bandwidth　of　14-kHz.　The　simulated　power　consumption　is　316　mu　W　with　a　1.2-V　supply　voltage　at　a　3.584MHz　sampling　clock.