K4T1G044QM Datasheet, PDF (14/29 Pages) Samsung semiconductor – 1Gb M-die DDR2 SDRAM Specification

1Gb M-die DDR2 SDRAM
DDR2 SDRAM
OCD default characteristics
Description
Output impedance
Output impedance step
size for OCD calibration
Pull-up and pull-down
mismatch
Output slew rate
Parameter
Sout
Min
12.6
0
0
1.5
Nom
18
Max
23.4
1.5
4
5
Unit
Notes
ohms 1,2
ohms 6
ohms 1,2,3
V/ns 1,4,5,6,7,8
Notes:
1. Absolute Specifications (0°C ≤ T_CASE ≤ +95°C; VDD = +1.8V ±0.1V, VDDQ = +1.8V ±0.1V)
2. Impedance measurement condition for output source dc current: VDDQ = 1.7V; VOUT = 1420mV;
(VOUT-VDDQ)/Ioh must be less than 23.4 ohms for values of VOUT between VDDQ and VDDQ-
280mV. Impedance measurement condition for output sink dc current: VDDQ = 1.7V; VOUT = 280mV;
VOUT/Iol must be less than 23.4 ohms for values of VOUT between 0V and 280mV.
3. Mismatch is absolute value between pull-up and pull-dn, both are measured at same temperature and
voltage.
4. Slew rate measured from V_IL(AC) to V_IH(AC).
5. The absolute value of the slew rate as measured from DC to DC is equal to or greater than the slew rate as
measured from AC to AC. This is guaranteed by design and characterization.
6. This represents the step size when the OCD is near 18 ohms at nominal conditions across all process and
represents only the DRAM uncertainty.
Output slew rate load :
VTT
Output
(VOUT)
25 ohms
Reference
Point
7. DRAM output slew rate specification applies to 400Mb/sec/pin and 533Mb/sec/pin speed bins.
8. Timing skew due to DRAM output slew rate mis-match between DQS / DQS and associated DQs is
included in tDQSQ and tQHS specification.
Page 14 of 29
Rev.1.1 Jan. 2005