Single-Ended Input Signals; Differential Output Signals; Differential Input Signals; Current Date: 8/3/94 - Adaptec AHA-2740W User Manual

Single-ended Input Signals

SCSI inputs meet the following electrical characteristics on each sig-
nal, including both receivers and passive drivers:
Signal Definition
V Low-level input voltage
IL
V High-level input voltage
IH
I Low-level input current
IL
I High-level input current
IH
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).

Differential Output Signals

Each signal sourced by a SCSI device shall have the following out-
put characteristics when measured at the SCSI device's connector:
VOD (differential output voltage) = 1,0V minimum
Shall conform to EIA RS-485 (ISO 8482-1982 TIA TR30.2)
All differential drivers shall maintain the high output impedance
during power-up and power-down cycles until the driver is
enabled.

Differential Input Signals

Each signal of a SCSI device shall have the following characteristics
when measured at the SCSI device's connector (including both
receivers and passive drivers):
Maximum input capacitance = 25 pF
Minimum input hysteresis = 35 millivolts
The input characteristics shall additionally conform to EIA RS-485
(ISO 8482-1982 TIA TR30.2).
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AHA-2740W/2742W/2744W User's Guide
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Current Date: 8/3/94

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Characteristics
0.0 to 0.8 volts DC (signal true)
2.0 to 5.25 volts DC (signal false)
-0.4 to 0.0 mA at V =0.5 volts DC
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0.0 to 0.1 mA at V =2.7 volts DC
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ECN Date: 8/9/94

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Specifications
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