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WEDPN16M64VR-XB2X
12
White Electronic Designs Corporation (602) 437-1520 www.whiteedc.com
White Electronic Designs
January 2005
Rev. 0
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. Specied values are obtained
with minimum cycle time and the outputs open.
4. Enables on-chip refresh and address counters.
5. The minimum specications are used only to indicate cycle time at which proper
operation over the full temperature range is ensured.
6. An initial pause of 100μs 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 specication, 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 denes 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 specications are tested after the device is properly initialized.
14. Timing actually specied by tCKS; clock(s) specied as a reference only at minimum
cycle rate.
15. Timing actually specied by tWR plus tRP; clock(s) specied as a reference only at
minimum cycle rate.
16. Timing actually specied by tWR.
17. Required clocks are specied 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 dened as a signal
cycling within timing constraints specied 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
rst 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.
AC FUNCTIONAL CHARACTERISTICS (NOTES 5,6,7,8,9,11,29)
Parameter/Condition
Symbol
-133
-125
-100
Units
READ/WRITE command to READ/WRITE command (17)
tCCD
111
tCK
CKE to clock disable or power-down entry mode (14)
tCKED
111
tCK
CKE to clock enable or power-down exit setup mode (14)
tPED
111
tCK
DQM to input data delay (17)
tDQD
000
tCK
DQM to data mask during WRITEs
tDQM
000
tCK
DQM to data high-impedance during READs
tDQZ
222
tCK
WRITE command to input data delay (17)
tDWD
000
tCK
Data-in to ACTIVE command (15)
tDAL
554
tCK
Data-in to PRECHARGE command (16)
tDPL
222
tCK
Last data-in to burst STOP command (17)
tBDL
1
tCK
Last data-in to new READ/WRITE command (17)
tCDL
111
tCK
Last data-in to PRECHARGE command (16)
tRDL
222
tCK
LOAD MODE REGISTER command to ACTIVE or REFRESH command (25)
tMRD
2
tCK
Data-out to high-impedance from PRECHARGE command (17)
CL = 3
tROH
333
tCK
CL = 2
tROH
222
tCK