DRAM
MT4C4001J
Austin Semiconductor, Inc.
NOTES:
point only; if tRAD is greater than the specified tRAD (MAX)
limit, then access time is controlled exclusively by tAA
1. All voltages referenced to Vss.
2. This parameter is sampled, not 100% tested. Capacitance
is measured with Vcc=5V, f=1 MHz at less than 50mVrms,
TA = 25°C ±3°C, Vbias = 2.4V applied to each input and
output individually with remaining inputs and outputs open.
3. Icc is dependent on cycle rates.
4. Icc is dependent on output loading and cycle rates.
Specified values are obtained with minimum cycle time and
the output open.
5. Enables on-chip refresh and address counters.
6. The minimum specifications are used only to indicate cycle
time at which proper operation over the full temperature range
.
19. Either tRCH or tRRH must be satisfied for a READ cycle.
20. tOFF (MAX) defines the time at which the output achieves
the open circuit conditions and is not referenced to VOH or
VOL
21. tWCS, tRWD, tAWD, and tCWD are not restrictive operating
parameters. tWCS applies to EARLY-WRITE cycles. tRWD
AWD, and tCWD apply to READ-MODIFY-WRITE cycles.
.
,
t
If tWCS > tWCS (MIN), the cycle is an EARLY-WRITE cycles
and the data output will remain an open circuit throughout the
entire cycle. If tRWD > tRWD (MIN), tAWD > tAWD (MIN) and
(-55°C < TA < 125°C) is assured.
7. An initial pause of 100µs is required after power-up
followed by eight RAS\ refresh cycles (RAS\-ONLY or CBR
with WE\ HIGH) before proper device operation is assured.
The eight RAS\ cycle wake-up should be repeated any time
the 16ms refresh requirement is exceeded.
tCWD > tCWD (MIN), the cycle is a READ-MODIFY-WRITE
and the data output will contain data read from the selected
cell. If neither of the above conditions is met, the state of the
data out is indeterminate. OE\ held HIGH and WE\ taken LOW
after CAS\ goes LOW results in a LATE-WRITE (OE\
8. AC characteristics assume tT = 5ns.
controlled) cycle. tWCS, tRWD, tCWD, and tAWD are not
applicable in a LATE-WRITE cycle.
22. These parameters are referenced to CAS\ leading edge in
EARLY-WRITE cycle and WE\ leading edge in LATE-WRITE
cycles and WE\ leading edge in LATE-WRITE or
READ-MODIFY-WRITE cycle.
9. VIH (MIN) and VIL (MAX) are reference levels for
measuring timing of input signals. Transition times are
measured between VIH and VIL (or between VIL and VIH).
10. In addition to meeting the transition rate specification, all
input signals must transit between VIH and VIL (or between
VIL and VIH) in a monotonic manner.
23. If OE\ is tied permanently LOW, LATE-WRITE or
READ-MODIFY-WRITE operations are not possible.
24. A HIDDEN REFRESH may also be performed after a
WRITE cycle. In this case, WE\=LOW and OE\=HIGH.
11. If CAS\ = VIH, data outputs (DQs) are High-Z.
12. If CAS\ = VIL, data outputs (DQs) may contain data from
the last valid READ cycle.
25. tWTS and tWTH are setup and hold specifications for the
WE\ pin being held LOW to enable the JEDEC test mode (with
CBR timing constraints). These two parameters are the
13. Measured with a load equivalent to two TTL gates and
100pF.
14. Assumes that tRCD < tRCD (MAX). If tRCD is greater than
the maximum recommended value shown in this table, tRAC
will increase by the amount that tRCD exceeds the value shown.
inverts of tWRP and tWRH in the CBR REFRESH cycle.
26. LATE-WRITE and READ-MODIFY-WRITE cycles must
have both tOD and tOEH met (OE\ HIGH during WRITE cycle)
in order to ensure that the output buffers will be open during
the WRITE cycle. The DQs will provide the previously read
data if CAS\ remains LOW and OE\ is taken back LOW after
15. Assumes that tRCD > tRCD (MAX)
16. If CAS\ is LOW at the falling edge of RAS\, DQs will be
maintained from the previous cycle. To initiate a new cycle
and clear the data out buffer, CAS\ must be pulsed HIGH for
tOEH is met. If CAS\ goes HIGH prior to OE\ going back LOW,
the DQs will remain open.
tCPN
.
17. Operation within the tRCD (MAX) limit ensures that tRAC
(MAX) can be met. tRCD (MAX) is specified as a reference
point only; if tRCD is greater than the specified tRCD (MAX)
27. The DQs open during READ cycles once tOD or tOFF
occur. If CAS\ goes HIGH first, OE\ becomes a “don’t care.”
If OE\ goes HIGH and CAS\ stays LOW, OE\ is not a “don’t
care;” and the DQs will provide the previously read data if
OE\ is taken back LOW (while CAS\ remains LOW).
28. JEDEC test mode only.
limit, then access time is controlled exclusively by tCAC
.
18. Operation within the tRAD (MAX) limit ensures that tRCD
(MAX) can be met. tRAD (MAX) is specified as a reference
AustinSemiconductor,Inc.reservestherighttochangeproductsorspecificationswithoutnotice.
MT4C4001J
Rev. 1.5 10/02
7
5秒后页面跳转
SG3525资料手册详解：SG3525参数分析、引脚说明、应用介绍
AT89C51单片机资料手册详细解析及应用示例
CP2102资料手册解读：CP2102引脚说明、关键参数分析
资料手册解读：UC3842参数和管脚说明
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
技术参数
数据手册
如果您发现信息不准确，
