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White Electronic Designs Corporation (602) 437-1520 www.whiteedc.com
WEDPN16M64VR-XBX
AC FUNCTIONAL CHARACTERISTICS (NOTES 5,6,7,8,9,11, 29)
Parameter/Condition
Symbol
-133
-125
-100
-66
Units
READ/WRITE command to READ/WRITE command (17)
tCCD
1
111
tCK
CKE to clock disable or power-down entry mode (14)
tCKED
1
111
tCK
CKE to clock enable or power-down exit setup mode (14)
tPED
1
111
tCK
DQM to input data delay (17)
tDQD
0
000
tCK
DQM to data mask during WRITEs
tDQM
0
000
tCK
DQM to data high-impedance during READs
tDQZ
2
222
tCK
WRITE command to input data delay (17)
tDWD
0
000
tCK
Data-in to ACTIVE command (15)
tDAL
5
544
tCK
Data-in to PRECHARGE command (16)
tDPL
2
222
tCK
Last data-in to burst STOP command (17)
tBDL
1
111
tCK
Last data-in to new READ/WRITE command (17)
tCDL
1
111
tCK
Last data-in to PRECHARGE command (16)
tRDL
2
222
tCK
LOAD MODE REGISTER command to ACTIVE or REFRESH command (25)
tMRD
2
222
tCK
Data-out to high-impedance from PRECHARGE command (17)
CL = 3
tROH
3
333
tCK
CL = 2
tROH
2
222
tCK
NOTES:
1. All voltages referenced to VSS.
2. This parameter is not tested but guaranteed by design. f = 1 MHz, TA = 25°C.
3. IDD is dependent on output loading and cycle rates. Specified values are
obtained with minimum cycle time and the outputs open.
4. Enables on-chip refresh and address counters.
5. The minimum specifications are used only to indicate cycle time at which
proper operation over the full temperature range is ensured.
6. An initial pause of 100s is required after power-up, followed by two
AUTO REFRESH commands, before proper device operation is ensured. (VCC
must be powered up simultaneously.) The two AUTO REFRESH command
wake-ups should be repeated any time the tREF refresh requirement is
exceeded.
7. AC characteristics assume tT = 1ns.
8. In addition to meeting the transition rate specification, the clock and CKE
must transit between VIH and VIL (or between VIL and VIH) in a monotonic
manner.
9. Outputs measured at 1.5V with equivalent load:
10. tHZ defines the time at which the output achieves the open circuit
condition; it is not a reference to VOH or VOL. The last valid data element will
meet tOH before going High-Z.
11. AC timing and IDD tests have VIL = 0V and VIH = 3V, with timing
referenced to 1.5V crossover point.
12. Other input signals are allowed to transition no more than once every two
clocks and are otherwise at valid VIH or VIL levels.
13. ICC specifications are tested after the device is properly initialized.
14. Timing actually specified by tCKS; clock(s) specified as a reference only
at minimum cycle rate.
15. Timing actually specified by tWR plus tRP; clock(s) specified as a
reference only at minimum cycle rate.
16. Timing actually specified by tWR.
17. Required clocks are specified by JEDEC functionality and are not
dependent on any timing parameter.
18. The ICC current will decrease as the CAS latency is reduced. This is due to
the fact that the maximum cycle rate is slower as the CAS latency is reduced.
19. Address transitions average one transition every two clocks.
20. CLK must be toggled a minimum of two times during this period.
21. VIH overshoot: VIH (MAX) = VCC + 2V for a pulse width - 3ns, and the
pulse width cannot be greater than one third of the cycle rate. VIL undershoot:
VIL (MIN) = -2V for a pulse width - 3ns.
22. The clock frequency must remain constant (stable clock is defined as a
signal cycling within timing constraints specified for the clock pin) during
access or precharge states (READ, WRITE, including tWR, and PRECHARGE
commands). CKE may be used to reduce the data rate.
23. Auto precharge mode only. The precharge timing budget (tRP) begins
7.5ns after the first clock delay, after the last WRITE is executed.
24. Precharge mode only.
25. JEDEC and PC100 specify three clocks.
26. Parameter guaranteed by design.
27. Self refresh available in commercial and industrial temperatures only.
28. OE high.
29. All AC timings do not count extra clock cycle needed on control signals
to be registered.