Document Type
Thesis
Date of Award
8-30-1989
Degree Name
Master of Science in Electrical Engineering - (M.S.)
Department
Electrical Engineering
First Advisor
William N. Carr
Second Advisor
Roy H. Cornely
Third Advisor
Durgamadhab Misra
Abstract
In this thesis work, a unique raicrosensor was designed for pressure measurements over the temperature range of -80 C to 125 C. The sensor has CMOS circuitry powered by a single voltage supply. It can be used for military and space applications including monitoring the pressure acting on the nose of the space shuttle.
The sensor consists of a thin silicon diaphragm, which is stressed by external pressure. Four resistors in a Wheatstone bridge configuration are diffused into the diaphragm. The temperature drift in the silicon sensors is dominated by the temperature dependence of the piezoresistive coefficients. The resistors are heavily doped to minimize the effect of ambient temperature. The piezoresistive effect with p - type resistors provides higher sensitivity compared with n type. The calculated intrinsic sensitivity of the sensor is 0.4 mV/V/psi and is linear over the pressure range of 0 to 15 psi. A single voltage power supply amplifying circuit is used to amplify the bridge output to levels in the range 1 to 4 volts. The pressure range sensed is 0 to 15 psi within an operating temperature range of -80 to 125 C. A full scale output voltage of 30 mV is obtained from the device with a power supply voltage of 5V.
The circuit simulation was done using SPICE modeling software. The Mentor Graphics IC layout editor was used for the chip physical layout.
Recommended Citation
Joshi, Abhay Mahadeo, "Semiconductor pressure sensor and amplifier with extended temperature range" (1989). Theses. 2793.
https://digitalcommons.njit.edu/theses/2793
