Adaptec AMM-1572 - Manual (Page 76)

A-4
AMM-1570/1572 User’s Guide
AMM-1570/1572 User’s Guide
Stock Number: 510526-00, Rev. B
Page: A-4
Print Spec Number: 492379-00
Current Date: 3/7/94
ECN Date: 3/8/94
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
A
A
A
A
A
A
A
A
A
A
A
A
A
A
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
AAAA
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
SCSI Interface
Electrical Interface
These are the specifications listed in ANSI X3.131-1986 for single-
ended operation.
Output Signals
All signals use open-collector or three-state drivers. Each signal
driven by a SCSI device has the following output characteristics
when measured at the SCSI device's connector:
Input Signals
SCSI inputs meet the following electrical characteristics on each sig-
nal, including both receivers and passive drivers:
Signal Definition Characteristics
V
OL
Low-level output voltage 0.0 to 0.5 volts DC at 48 mA sinking
(signal assertion)
V
OH
High-level output voltage 2.5 to 5.25 volts DC (signal negation)
Signal Definition Characteristics
V
IL
Low-level input voltage 0.0 to 0.8 volts DC (signal true)
V
IH
High-level input voltage 2.0 to 5.25 volts DC (signal false)
I
IL
Low-level input current -0.4 to 0.0 mA at V
1
=0.5 volts DC
I
IH
High-level input current 0.0 to 0.1 mA at V
1
=2.7 volts DC
Minimum input hysteresis = 0.2 volts DC.
Maximum input capacitance = 25 pF (measured at the device connector closest
to the stub, if any, within the device).