TolerANTTechnology Electrical Characteristics 6-5
6.2 TolerANT Technology Electrical Characteristics
The LSI53C875A features TolerANT technology, which includes active
negation on the SCSI drivers and input signal filtering on the SCSI
receivers. Active negation actively drives the SCSI Request,
Acknowledge, Data, and Parity signals HIGH rather than allowing them
to be passively pulled up by terminators. Tab le 6.1 1 providese lectrical
characteristics for SE SCSI signals. Figure 6.1 thr ough Figure6.5
provide reference information for testing SCSI signals.
Table 6.9 Output Signals—IRQ/, MAC/_TESTOUT,REQ/
Symbol Parameter Min Max Unit Test Conditions
VOH Output high voltage 0.9 VDD VDD V16 mA
VOL Output low voltage VSS 0.1 VDD V16mA
IOZ 3-state leakage 10 10 µA–
IPULL Pull-downcurrent - only
on IRQ/ 50 12.5 µA–
Table 6.10 Output Signa l—SERR/
Symbol Parameter Min Max Unit Test Conditions
VOL Output low voltage VSS 0.1 VDD V16mA
IOZ 3-state leakage 10 10 µA–