The fault-free response at the FRWC output, Vo,
is a 3-bit binary pattern (010) at the end of each test
cycle. In order to achieve high fault coverage, each of
the 7 resistors used in the self test circuit as shown in
Fig. 1 is implemented with a serial/parallel resistor
network shown in Fig. 2. Our investigations have
confirmed that based on single fault assumption, the
availability of three input voltage settings coupled
with the built-in fault tolerant resistor structure just
mentioned, an effective self-testable FRWC with high
fault coverage can be realized.