three-quarters to maximum track.

General Notes from Table 2:

1.Minimum current loading for each supply voltage is not less than 1.2% of the maximum operating current shown.

2.The +5 and +12 volt supplies shall employ separate ground returns.

3.Where power is provided to multiple drives from a common supply, careful consideration for individual drive power requirements should be noted. Where multiple units are powered on simultaneously, the peak starting current must be available to each device.

4.Parameters, other than spindle start, are measured after a 10-minute warm up.

5.No terminator power.

6.2.1Conducted noise immunity

Noise is specified as a periodic and random distribution of frequencies covering a band from DC to 20 MHz. Maximum allowed noise values given below are peak to peak measurements and apply at the drive power con- nector.

+5

V

=

250 mV pp from 100 Hz to 20 MHz.

+12

V

=

800 mV pp from 100 Hz to 8 KHz.

 

 

 

450 mV pp from 8 KHz to 20

KHz.

 

 

 

250 mV pp from 20 KHz to 5

MHz.

6.2.2Power sequencing

The drive does not require power sequencing. The drive protects against inadvertent writing during power-up and down. Daisy-chain operation requires that power be supplied to the SCSI bus terminator to ensure proper termination of the peripheral I/O cables. To automatically delay motor start based on the target ID (SCSI ID) enable the Delay Motor Start option and disable the Enable Motor Start option on the J2 connector on LW mod- els or on the backplane for LC models. See Section 8.1 for pin selection information. To delay the motor until the drive receives a Start Unit command, enable the Enable Remote Motor Start option on the J2 connector on LW models or on the backplane for LC models.

6.2.312 V - Current profile

Figure 2, 4 and 6 identify the drive +12 V current profiles and figures 3, 5 and 7 identify the drive +5 V current profiles. The current during the various times is as shown:

T0 - Power is applied to the drive.

T1 - Controller self tests are performed.

T2 - Spindle begins to accelerate under current limiting after performing drive internal diagnostics. See Note 1 of Table 2.

T3 - The spindle is up to speed and the head-arm restraint is unlocked.

T4 - The adaptive servo calibration sequence is performed.

T5 - Calibration is complete and drive is ready for reading and writing.

Note. All times and currents are typical. See Table 2 for maximum current requirements.

Cheetah 10K.7 SCSI Product Manual, Rev. D

27

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Image 37
Seagate ST3300007LW/LC, ST3146707LW/LC, ST373207LW/LC Conducted noise immunity, Power sequencing, 3 12 V Current profile

ST3300007LW/LC, ST373207LW/LC, ST3146707LW/LC specifications

Seagate's ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC are part of the company's renowned line of hard disk drives (HDDs), specifically designed for enterprise and high-performance computing environments. With their reliability and performance, these drives have become popular choices for data centers and critical applications requiring extensive storage capabilities.

One of the standout features of these models is their capacity to handle large volumes of data. The ST3146707LW/LC has a capacity of 146GB, while the ST373207LW/LC offers 73GB, and the ST3300007LW/LC comes with a substantial 300GB. These capacities make them well-suited for applications that require not only high storage space but also rapid access to data.

In terms of performance, these drives utilize a 10,000 RPM spindle speed, which significantly enhances data access times and overall performance. The combination of fast rotational speeds with Seagate's advanced caching algorithms allows for swift data retrieval, making these drives ideal for environments where speed is crucial.

These HDDs also employ the SCSI (Small Computer System Interface) interface, which promises high data transfer rates and reliability in enterprise-level applications. The Ultra320 SCSI interface can support transfer rates up to 320 MB/s, ensuring that the drives can efficiently communicate with other system components.

Another key technology featured in these models is Seagate's Adaptive Error Correction technology, which enhances data integrity and reliability. This feature helps in the detection and correction of errors that can occur during data transfer, reducing the risk of data loss.

Performance consistency is critical in enterprise environments, and these drives are built to endure the demands of 24/7 operation. They are designed with robust mechanisms to withstand temperature fluctuations, shock, and vibrations commonly found in data center settings.

In summary, the Seagate ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC hard drives exemplify advanced features and technologies tailored for enterprise storage solutions. With significant capacities, impressive spindle speeds, SCSI connectivity, and reliability-focused technologies, these drives remain a valuable asset for businesses relying on stable and high-performance data storage.