Filter
Top Products
Barracuda 7200.11 Serial ATA Product Manual, Rev. G 17
2.9 Acoustics
Drive acoustics are measured as overall A-weighted acoustic sound power levels (no pure tones). All mea-
surements are consistent with ISO document 7779. Sound power measurements are taken under essentially
free-field conditions over a reflecting plane. For all tests, the drive is oriented with the cover facing upward.
Note. For seek mode tests, the drive is placed in seek mode only. The number of seeks per second is defined
by the following equation:
(Number of seeks per second = 0.4 / (average latency + average access time)
*During periods of drive idle, some offline activity may occur according to the S.M.A.R.T. specification, which may increase acoustic and
power to operational levels.
2.9.1 Test for Prominent Discrete Tones (PDTs)
Seagate follows the ECMA-74 standards for measurement and identification of PDTs. An exception to this
process is the use of the absolute threshold of hearing. Seagate uses this threshold curve (originated in ISO
389-7) to discern tone audibility and to compensate for the inaudible components of sound prior to computation
of tone ratios according to Annex D of the ECMA-74 standards.
2.10 Electromagnetic immunity
When properly installed in a representative host system, the drive operates without errors or degradation in
performance when subjected to the radio frequency (RF) environments defined in the following table:
Table 5: Fluid Dynamic Bearing (FDB) motor acoustics
Idle* Performance Seek Quiet Seek
ST31000340AS, ST31000640AS,
ST3750330AS, ST3750630AS,
ST3640330AS and ST3640630AS
2.9 bels (typ)
3.1 bels (max)
3.2 bels (typ)
3.3 bels (max)
3.1 bels (typ)
3.2 bels (max)
ST3500320AS, ST3500620AS and
ST3500820AS
2.7 bels (typ)
2.9 bels (max)
3.1 bels (typ)
3.2 bels (max)
3.0 bels (typ)
3.1 bels (max)
Table 6: Radio frequency environments
Test Description Performance level Reference standard
Electrostatic
discharge
Contact, HCP, VCP: ± 4
kV; Air: ± 8 kV B EN 61000-4-2: 95
Radiated RF
immunity
80 to 1,000 MHz, 3 V/m,
80% AM with 1 kHz sine
900 MHz, 3 V/m, 50% pulse modulation @ 200 Hz
A EN 61000-4-3: 96
ENV 50204: 95
Electrical fast
transient
± 1 kV on AC mains, ± 0.5 kV on external I/O B EN 61000-4-4: 95
Surge immunity ± 1 kV differential, ± 2 kV common, AC mains B EN 61000-4-5: 95
Conducted RF
immunity
150 kHz to 80 MHz, 3 Vrms, 80% AM with 1 kHz sine A EN 61000-4-6: 97
Voltage dips,
interrupts
0% open, 5 seconds
0% short, 5 seconds
40%, 0.10 seconds
70%, 0.01 seconds
C
C
C
B
EN 61000-4-11: 94