Patent ID: 7246330

Claim:
An LDMOS device with a body diode current detector, comprising: (a) an n-well in a semiconductor substrate and extending to a surface of said semiconductor substrate; (b) a first p-region in said semiconductor substrate and extending to said surface, said first p-region surrounded by said n-well; (c) an n+drain region in said semiconductor substrate and extending to said surface, said drain region surrounded by said n-well; (d) an n+source region in said semiconductor substrate and extending to said surface, said source region surrounded by said first p-region and coupled to said p-region; (e) a first insulated gate over said first p-region between said source region said n-well; (f) a second p-region in said semiconductor substrate and extending to said surface, said second p-region surrounded by said n-well; (g) an n+collector region in said semiconductor substrate and extending to said surface, said collector region surrounded by said second p-region, said collector region coupled through a pull-up resistor to a voltage supply; and (h) a second insulated gate over said second p-region between said collector region and said n-well, said second insulated gate coupled to said source region and to said second p-region; (i) wherein when a first body diode formed by said first p-region and said n-well conducts a first current during operation of the LDMOS formed with said source region, said drain region, and said first insulated gate, a second body diode formed by said second p-region and said n-well conducts a second current through said collector region to said pull-up resistor; (j) whereby said first current conducted by said first body diode can be detected by measurement of said second current through said collection region to said pull-up resistor.