Seagate ST936701LC - Savvio 36.7 GB Hard Drive, Руководство по эксплуатации продукта

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Savvio SCSI Product Manual, Rev. C 59
LVD input characteristics
Each differential signal received by LVD interface receiver circuits shall have the following input characteristics
when measured at the disc drive connector:
Steady state Low level input differential voltage = 0.030 V = < V
in
= < 3.6 V (signal negation/logic 0)
Steady state High level input differential voltage = –3.6 V = < V
in
= < –0.030 V (signal assertion/logic 1)
Differential voltage = +0.030 V minimum with common-mode voltage range 0.845 V = < V
cm
= < 1.655 V.
(T10/1302D revision 14, section A.3.2).
Figure 16. Typical SE-LVD alternative transmitter receiver circuits
9.7.1.1 General cable characteristics
The 80-pin connector option provided on LC models is intended for use on drives that plug directly into back-
plane connector in the host equipment. In such installations, all backplane wiring segments are subject to the
electromagnetic concepts presented in Standard T10/1365D, Rev. 3, Section 6. For LC model drives, installa-
tions with cables are not recommended.
9.7.1.2 Single-ended drivers/receivers
Single-ended I/O pin assignments are shown in Table 20. The LC model drives do not require an I/O cable.
These models are designed to connect directly to a back panel connector.
9.8 Terminator requirements
These drives do not have onboard internal terminators. The user, systems integrator or host equipment manu-
facturer must provide a terminator arrangement external to the drive when termination is required. LC model
drives are designed to be plugged into a backpanel connector without cabling.
9.8.1 Terminator power
These drives cannot furnish terminator power because no conductors in the 80-pin I/O connector are devoted
to terminator power.
VCCA VCCB
Single
Ended
Circuitry Single
Ended
Receiver Single
Ended
Negation
Driver
Single
Ended
Assertion
Driver
Single
Ended
Ground
Driver
Single Ended:
LVD:
LVD Signal Drivers
LVD Signal Drivers
LVD
Receiver
Ground
GND
+Signal
—Signal
—Signal