Created: 10/19/99

CALCE EPSC Graduate Student Theses (1988)

Resch, Cheryl Lynn (M.S. Mechanical Engineering)

Calculation and Measurment of Temperature Profiles of Electronic Printed Wiring Boards

The temperature characteristics of printed wiring boards (PWBs) are investigated and a computer program for calculating the PWB temperature profile and the temperatures of individual components is described.

Yeun Tsun Wong (M.S. Mechanical Engineering)

Steiner Tree Oriented Placement

Presented is a new design methodology for the placement of components on a printed wiring board (PWB). By simulating the connection and the movement of a node in a tree in a placement step, an iso-distance error graph (IDEG) which contains connection errors generated by replacing a Steiner tree with its equivalent not-Steiner tree is developed and is used to estimate how well a non-Steiner tree functions as a Steiner tree.

To reduce connection errors in the IDEG and pursue the computational efficiency, a row-based tree family, in which the tree length is dependent on the terminal coordinates of each row, is constructed. Based on the analysis of the error distribution on the IDEG of a row-based tree and practical tests, the row-based tree functions better than the minimum spanning tree does and a minimum or nearly minimum total Steiner tree length can be obtained by minimizing the total row-based tree length.