Windbond Electronics W631GG6KB series of 1Gb DDR3 SDRAM comes in 3 speeds, 2 temp ranges and 2 packaging options.
-11 is compliant to the DDR3-1866 (13-13-13) Specification (Clock Freq 933 MHz)
-12 is compliant to the DDR3-1600 (11-11-11) Specification (Clock Freq 800 MHz)
-15 is compliant to the DDR3-1333 (9-9-9) Specification (Clock Freq 667 MHz)
The Standard parts are 0°C ≤ TCASE ≤ 95°C
The 12I and 15I parts are -40°C ≤ TCASE ≤ 95°C
Standard Packaging is Tray
with additional TR the part will be Tape & Reel