such a structure n well region 220 and guardring region 200 may sufficiently absorb electrons emitted from drain region 160 and the electrons flow into lv device 400 so that the occurrence of noise can be prevented n well region 220 has a structure where an n type dopant is formed in a shallow n well sn well and the sn well is surrounded by hv well 380 p well region 260 has a structure where a p type dopant is implanted in the sp well p well region 260 is electrically connected to n well region 220 from this electrons absorbed in n well region 220 may transfer to p well region 260 guardrings 240 are formed at both sides of p well region 260 guardring 240 has a structure where an n type dopant is implanted and is formed adjacent to p well region 260 and device isolation layer 180 p well region 260 and guardring 240 are surrounded by hv well 380 guardring 240 absorbs electrons emitted from drain region 160 and also absorbs electrons emitted from p well region 260 simultaneously to prevent electrons from flowing into lv device 400 in more detail as illustrated in example fig2 some electrons e emitted from the drain region flow into n well region 220 and the remaining electrons e pass through n well region 220 the electrons flowing into n well region 220 transfer into guardring region 200 i e p well region 260 and then are emitted from p well region 260 as mentioned hereinabove the electrons e emitted from p well region 260 are re absorbed in.