A pressure sensor die assembly (100, 230, 300), comprising: a base substrate (102, 202a, 202b, 302) having a first surface; a stop structure (106, 206a, 206b, 306) on the first surface of the base substrate; and a diaphragm structure (110, 210a, 210b, 310) coupled to the first surface of the base substrate, characterized by the diaphragm structure comprising: a first side with a stepped section that defines a cavity, wherein a first portion (116, 212) of the cavity has a first depth, and a second portion (118, 214) of the cavity has second depth that is less than the first depth; a pressure sensing diaphragm portion (112, 216, 312) having a first thickness, the pressure sensing diaphragm portion located over and spaced apart from the stop structure such that the stop structure protrudes into the first portion of the cavity; and an over pressure diaphragm portion (114, 218, 314) having a second thickness that is greater than the first thickness of the pressure sensing diaphragm portion, wherein the over pressure diaphragm portion surrounds the pressure sensing diaphragm portion; wherein the second portion of the cavity provides a gap between the first surface of the base substrate and the over pressure diaphragm portion; wherein when an over pressure is applied to the diaphragm structure, at least some area of the pressure sensing diaphragm portion is deflected and supported by the stop structure, and as the over pressure is increased, the over pressure diaphragm portion deflects and engages with the first surface of the base substrate such that additional area of the pressure sensing diaphragm portion is deflected and supported by the stop structure. a base substrate (102, 202a, 202b, 302) having a first surface; a stop structure (106, 206a, 206b, 306) on the first surface of the base substrate; and a diaphragm structure (110, 210a, 210b, 310) coupled to the first surface of the base substrate, characterized by the diaphragm structure comprising: a first side with a stepped section that defines a cavity, wherein a first portion (116, 212) of the cavity has a first depth, and a second portion (118, 214) of the cavity has second depth that is less than the first depth; a pressure sensing diaphragm portion (112, 216, 312) having a first thickness, the pressure sensing diaphragm portion located over and spaced apart from the stop structure such that the stop structure protrudes into the first portion of the cavity; and an over pressure diaphragm portion (114, 218, 314) having a second thickness that is greater than the first thickness of the pressure sensing diaphragm portion, wherein the over pressure diaphragm portion surrounds the pressure sensing diaphragm portion; a first side with a stepped section that defines a cavity, wherein a first portion (116, 212) of the cavity has a first depth, and a second portion (118, 214) of the cavity has second depth that is less than the first depth; a pressure sensing diaphragm portion (112, 216, 312) having a first thickness, the pressure sensing diaphragm portion located over and spaced apart from the stop structure such that the stop structure protrudes into the first portion of the cavity; and an over pressure diaphragm portion (114, 218, 314) having a second thickness that is greater than the first thickness of the pressure sensing diaphragm portion, wherein the over pressure diaphragm portion surrounds the pressure sensing diaphragm portion; wherein the second portion of the cavity provides a gap between the first surface of the base substrate and the over pressure diaphragm portion; wherein when an over pressure is applied to the diaphragm structure, at least some area of the pressure sensing diaphragm portion is deflected and supported by the stop structure, and as the over pressure is increased, the over pressure diaphragm portion deflects and engages with the first surface of the base substrate such that additional area of the pressure sensing diaphragm portion is deflected and supported by the stop structure.