A method and apparatus implement effective testing of a sense amplifier
for an eFuse without having to program or blow the eFuse, and a design
structure on which the subject circuit resides is provided. After initial
processing of the sense amplifier, testing determines whether the sense
amplifier can generate a valid "0" and "1" before programming the eFuse.
A first precharge device and a second precharge device that normally
respectively precharge a true sense node and a complement sense node to a
high voltage are driven separately. For testing, one of the precharge
devices is conditionally held off to insure the sense amplifier results
in a "0" and "1". This allows the testing of the sense amplifier devices
as well as down stream connected devices. Once testing is complete, both
precharge devices are controlled in tandem.