Constellation.2 Serial ATA Product Manual, Rev. B 5

Table 1: Drive specifications summary for 1TB, 500 and 250 GB models
Drive specification ST91000640NS
ST91000641NS
ST91000642NS
ST9500620NS
ST9500621NS
ST9500622NS
ST9250610NS
ST9250611NS
ST9250612NS
Formatted GB (512 bytes/sector)* 1000 500 250
Guaranteed sectors 1,953,525,168 976,773,168 488,397,168
Heads 842
Discs 421
Bytes per sector 512
Default sectors per track 63
Default read/write heads 16
Default cylinders 16,383
Recording density, KBPI (Kb/in max) 1544
Track density, KTPI (Ktracks/in avg.) 270
Areal density, (Gb/in2 avg) 417
Spindle speed (RPM) 7200
Internal data transfer rate (Mb/s max) 1304
Sustained data transfer rate OD (MB/s max) 115
I/O data-transfer rate (MB/s max) 600
ATA data-transfer modes supported PIO modes 0–4
Multiword DMA modes 0–2
Ultra DMA modes 0–6
Cache buffer 64 Mbytes
Height (mm max) 14.8 mm (0.583 in)
Width (mm max) 70.0 mm (2.76 in)
Length (mm max) 100.5 mm (3.957 in)
Weight (max) 200 g (0.441 lb) 183 g (0.403 lb) 179 g (0.395 lb)
Average latency 4.16 ms
Power-on to ready (sec max) 20 sec
Standby to ready (sec max) 13 sec
Track-to-track seek time (ms typical) 0.7 read; 0.85 write
Average seek, read (ms typical) 8.5
Average seek, write (ms typical) 9.5
Startup current (typical) 12V (peak) 2.0 amps
Voltage tolerance (including noise) 5V +10 / -7.5%
12V +10 / -7.5%
Ambient temperature 5° to 60°C (operating)
–40° to 70°C (nonoperating)
Temperature gradient (°C per hour max) 20°C (operating)
20°C (nonoperating)
Relative humidity 5% to 95% (operating)
5% to 95% (nonoperating)
Relative humidity gradient 20% per hour max
Wet bulb temperature (°C max) 28°C
Altitude, operating –60.96 m to 3,048 m
(–200 ft. to 10,000+ ft.)
Altitude, nonoperating
(below mean sea level, max) –60.96 m to 12,192 m
(–200 ft. to 40,000+ ft.)
Operational Shock (max at 2 ms) Read 70 Gs / Write 40 Gs
Non-Operational Shock (max at 2 ms) 400 Gs