April 24, 2006 -- Today’s circuit designs demand higher packaging density, faster performance, and mixed analog-digital solutions. The resulting increase in power densities is prevalent for designs such as smart power integrated chips, high-speed channel transceivers, microcontrollers, LCD display circuits, automotive electronics, precision data converters, voltage references, sensors, medical electronic devices, and wireless products. Analog circuit behavior can vary significantly with temperature, and temperature gradients across circuits can lead to higher failure rates.

To address these design challenges, temperature analysis must be included in the design process. The circuit design process must include a better methodology to understand the heat flow from the die through the package and the heat flow within the die.

Understanding on-die temperatures resulting from heat flow permits a circuit designer to address the sensitivity of the circuitry to temperature variations throughout the design process. A better understanding of the temperature variations in the design provides the circuit designer with insight into where to place temperature sensors and focus design efforts on design challenges such as reliability.

A design flow methodology that provides temperature variations with an understanding of the electro-thermal interaction is required for today’s analog and mixed-signal designs. These design challenges and the methodology to address them are covered in this document.

By Rajit Chandra, Ph.D. and Adi Srinivasan. (Chandra is founder, president and CEO of Gradient Design Automation and Srinivasan is a senior engineer at Gradient.)