Patent ID: 7327595

Claim:
A dynamically read fuse cell, comprising: a first circuit which includes a known reference resistance R ref and at least two inputs, said first circuit arranged to receive a “read” signal at one of said inputs and to produce a first output which begins changing state in response to said “read” signal and has a slew rate which varies with R ref ; and a second circuit which includes a programmed fuse having a resistance R fuse and at least two inputs, said second circuit arranged to receive said “read” signal at one of said inputs and to produce a second output which begins changing state in response to said “read” signal and has a slew rate which varies with R fuse ; said first and second circuits interconnected such that the output of each of said circuits is connected to an input of the other of said circuits, such that causing both outputs to begin changing state in response to the common “read” signal triggers a time domain race condition, the result of which indicates which of said outputs slewed more quickly in response to said “read” signal, thereby indicating the relationship between R ref and R fuse .