Time Domain Reflectometry (TDR)
Timing measurements of reflected signals in packaged parts. Comparison to a known good part establishes deviation point of failing part. Used to identify location of failure to substrate, interconnect or die.
Each layer in the package may be inspected optically and probed electrically.
TDR ON BGA, TWO PINS CHECKED
TDR ON BGA, TWO PINS CHECKED
Top layer of substrate removed
TDR ON BGA, TWO PINS CHECKED
Last layer of substrate removed
