Seagate ST336918N, ST318418N, ST318438LW, ST336938LW manual Input characteristics, LVD output signals

Barracuda 36ES2 Product Manual, Rev. B 69

Output characteristics

Each signal (Vs) driven by LVD interface drivers shall have the following output characteristics when measured at the disc drive connector:

Steady state Low level output voltage* = –.95 V = < Vs = < –1.55 V (signal negation/logic 0)
Steady state High level output voltage* = –.95 V = < Vs = < 1.55 V (signal assertion/logic 1)
		￿￿￿		￿￿￿￿￿￿￿			￿￿￿￿	￿￿
￿	￿￿￿￿￿				voltage	ranges 0.700 V = < Vcm = < 1.800 V.
￿￿￿￿￿￿
Differential voltage = +0.6 V minimum with common-mode
*These voltages shall be measured between the output terminal and						the SCSI device’s logic ground reference.
			￿	￿		￿￿￿
					￿
The output characteristics shall additionally conform to EIA RS-485.							￿￿￿￿	￿￿
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				￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

Figure 22. LVD output signals

Input characteristics

Each signal (Vs) received by LVD interface receiver circuits shall have the following input characteristics when measured at the disk drive connector:

Steady state Low level output voltage* = 0.030 V = < Vs = < 3.6 V (signal negation/logic 0) Steady state High level output voltage* = –3.6 V = < Vs = < –0.030 V (signal assertion/logic 1)

Differential voltage = +0.30 V minimum with common-mode voltage ranges 0.700 V = < Vcm = < 1.800 V. (X3T10/1302D)

*These voltages shall be measured between the￿￿￿￿output terminal and the￿￿￿￿SCSI device’s logic ground reference.

Input characteristics shall additionally￿￿￿￿￿￿￿￿￿￿￿ conform to EIA￿￿￿￿￿￿RS￿￿￿￿￿-485￿￿-983￿￿￿￿. ￿￿￿￿ ￿￿￿￿￿

￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

Figure 23. Typical SE-LVD alternative transmitter receiver circuits