In　order　to　meet　a　number　of　industries　hardware　that　require　high　reliability　and　large　amount　of　code,　this　paper　gives　a　model-based　design　(MBD)　workflow　compliance　with　DO-254　standard　for　hardware　development　process.　Taking　the　Digital　down　conversion　(DDC)　for　example;　this　paper　has　described　how　to　use　the　tool　chain　of　Simulink,　HDL　Coder　and　Modelsim　to　complete　the　entire　development　process.　In　this　way,　we　can　build　a　DDC　model　starting　from　requirements　analysis　to　functional　verification　and　system　testing　of　the　model,　fixed-point　optimization,　code　generation,　and　then　validation　the　DDC　system　on　XUPV5　board　in　visual　development　environment.　The　entire　process　which　starts　from　design　concept　to　hardware　implementation　always　focuses　on　the　DDC　model　for　continuous　testing　and　verification.　In　this　way,　we　can　verify　and　validate　the　correctness　of　the　design　of　DDC　in　three　different　levels,　so　that　design　flaws　could　be　exhumed　in　the　early　stages　of　the　development.　The　proposed　solution　is　not　only　overcoming　the　flaws　of　low　efficiency　and　difficulty　of　meeting　the　requirements　in　traditional　methods　of　development,　but　also　to　avoid　the　potential　risk　in　technology　and　market.　©　2012　IEEE.