X0202 4 2008-01-04 0 0001280452 MONOLITHIC POWER SYSTEMS INC MPWR 0001308676 Hsing Michael 6409 GUADALUPE MINES ROAD SAN JOSE CA 95120 1 1 0 0 CEO Common Stock 2008-01-04 4 S 0 200 19.97 D 84897 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.03 D 84697 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 300 20.06 D 84397 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.08 D 84297 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.13 D 84097 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.15 D 83997 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.16 D 83897 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 400 20.18 D 83497 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.19 D 83297 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 400 20.2 D 82897 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.21 D 82697 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.22 D 82497 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.23 D 82397 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 200 20.24 D 82197 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 300 20.25 D 81897 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 400 20.28 D 81497 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.31 D 81397 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.34 D 81297 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.35 D 81197 I By Jointly w/Spouse Common Stock 2008-01-04 4 S 0 100 20.39 D 81097 I By Jointly w/Spouse Common Stock 822144 D Common Stock 133040 I By S. Hsing 04 Trust Common Stock 133040 I by M Hsing 04 Trust In accordance with the reporting person's 10b5-1 trading plan. By: Adriana Chiocchi For: Michael Hsing 2008-01-07