Here is the abstract you requested from the ExCold_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Extreme Temperature Invariant Circuitry Through Adaptive Body Biasing and Supply Voltage Scaling|
|Keywords: Adaptive Body bias, Adaptive Supply Voltage, Low and High temperature circuits|
|This presentation presents the design, modeling and simulation of a Quadrature 435 MHz VCO that can verifiably operate over a temperature range of -230C to +180C in CMOS SOI technology. This result is achieved by using the body node as a 4th transistor terminal and a generating circuit to apply a DC “correction” bias to this terminal to negate the extreme temperature effects. The project also discovered that there is a critical biasing point and it is not required to correct all of the transistors in the VCO. Only the DC Biasing transistor of the VCO needs to be corrected to gain room temperature operation. The VCO was simulated using BSIM3v3 transistor models that have been physically corrected and verified for correct operation down to -140C through the use of a cold chamber. The presentation will also discuss further implementation of adaptive circuit techniques, such as both adaptive body biasing and adaptive supply voltage scaling, using the corrected models to produce a Quadrature 435MHz PLL. Utilizing these techniques discussed in the presentation will aid future designers in designing for extreme temperature environments and low power.|
|Wallace Shepherd Pitts, Doctoral Research Assistant
North Carolina State University