A memory circuit comprises a memory and a first test circuit coupled to
the memory. The first test circuit is configured to compare data read
from memory cells with expected data for the memory cells to provide a
first set of pass/fail signals for the memory cells, compress the first
set of pass/fail signals for the memory cells into a second pass/fail
signal, latch the second pass/fail signal in response to a data valid
signal, maintain the latch of the second pass/fail signal if the second
pass/fail signal indicates a failed test, combine the second pass/fail
signal and a third pass/fail signal of a second test circuit to provide a
fourth pass/fail signal, and pass the fourth pass/fail signal to a third
test circuit.