SDRAM
AS4SD2M32
Austin Semiconductor, Inc.
18. The IDD current will increase or decrease proportionally ac-
cording to the amount of frequency alteration for the test con-
dition.
19. Address transitions average one transition every two clocks.
20. CLK must be toggled a minimum of two times during this
period.
NOTES:
1. All voltages referenced to VSS.
2. This parameter is sampled. VDD, VDDQ = +3.3V; f = 1 MHz, TA
= 25°C; pin under test biased at 1.4V.
3. IDD is dependent on output loading and cycle rates. Speci-
fied values are obtained with minimum cycle time and the out-
puts open.
21. Based on tCK = 7.5ns for -75.
22. VIH overshoot: VIL (MAX) = VDDQ = 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.
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:
(0°C <TA < +125°C for XT), (-40°C <TA < +85°C
23. 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.
24. Auto precharge mode only. The precharge timing budget
(tRP) begins 7.5ns after the first clock delay, after the last WRITE
is executed. May not exceed limit set for precharge mode.
25. Precharge mode only.
for IT), and (-45°C <TA < +105°C for ET).
6. An initial pause of 100μs is required after power-up, followed
by two AUTO REFRESH commands, before proper device op-
eration is ensured. (VDD and VDDQ must be powered up simul-
taneously. VSS and VSSQ must be at the same potential.) The
two AUTO REFRESH command wake-ups should be repeated
any time the tREF refresh requirement is
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.
exceeded.
26. JEDEC and PC100 specify three clock.
27. for -75 at CL = 3 with no load is 4.6ns and is guaranteed by
design.
9. Outputs measured at 1.5V with equivalent load:
28. Parameter guaranteed by design.
29. PC100 specifies a maximum of 4pF.
30. PC100 specifies a maximum of 5pF.
31. PC100 specifies a maximum of 6.5pF.
Q
50pF
32. CL = 3 and tCK = 7.5ns.
33. CKE is HIGH during refresh command period tRFC (MIN) else
CKE is LOW. The IDD6 limit is actually a nominal value and
does not result in a fail value.
34. 64ms refresh for IT, ET temperature options, 16ms refresh
for XT temperature option.
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 operating and IDD test conditions have VIL = 0V and VIH
= 3.0V using a measurement reference level of 1.5V. If the input
transition time is longer than 1ns, then the timing is measured
from VIL (MAX) and VIH (MIN) and no longer from the 1.5V
mid-point.
35. Self refresh mode available for IT and ET only.
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. IDD specifications are tested after the device is properly ini-
tialized.
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.
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
AS4SD2M32
Rev. 1.0 1/08
30