W3J128M72G-XLBX
W3J128M72G-XPBX
October 2011 © 2011 Microsemi Corporation. All rights reserved. 36 Microsemi Corporation • (602) 437-1520 • www.whiteedc.com
Rev. 12 www.microsemi.com/pmgp
Microsemi Corporation reserves the right to change products or specifi cations without notice.
NOTES:
1. Parameters are applicable with 0°C TC +95°C and VCC/VCCQ = +1.5V ±0.075V.
2. All voltages are referenced to VSS.
3. Output timings are only valid for RON34 output buffer selection.
4. Unit “tCK (AVG)” represents the actual tCK (AVG) of the input clock under operation. Unit “CK”
represents one clock cycle of the input clock, counting the actual clock edges.
5. AC timing and ICC tests may use a VIL-to-VIH swing of up to 900mV in the test environment,
but input timing is still referenced to VREF (except tIS, tIH, tDS, and tDH use the AC/DC trip points
and CK, CK# and DQS, DQS# use their crossing points). The minimum slew rate for the input
signals used to test the device is 1 V/ns for single ended inputs and 2 V/ns for differential inputs
in the range between VIL(AC) and VIH(AC).
6. All timings that use time-based values (ns, s, ms) should use tCK (AVG) to determine the
correct number of clocks (AC Operation Table). In the case of non integer results, all minimum
limits are to be rounded up to the nearest whole integer, and all maximum limits are to be
rounded down to the nearest whole integer.
7. The use of “strobe” or “DQSDIFF” refers to the DQS and DQS# differential crossing point when
DQS is the rising edge. The use of “clock” or “CK” refers to the CK and CK# differential crossing
point when CK is the rising edge.
8. This output load is used for all AC timing (except ODT reference timing) and slew rates. The
actual test load may be different. The output signal voltage reference point is VCCQ/2 for single-
ended signals and the crossing point for differential signals.
9. NOTE: When operating in DLL disable mode, WEDC does not warrant compliance with normal
mode timings or functionality.
10. The clock’s tCK (AVG) is the average clock over any 200 consecutive clocks and tCK(AVG) MIN is
the smallest clock rate allowed, with the exception of a deviation due to clock jitter. Input clock
jitter is allowed provided it does not exceed values specifi ed and must be of a random Gaussian
distribution in nature.
11. Spread spectrum is not included in the jitter specifi cation values. However, the input clock can
accommodate spread-spectrum at a sweep rate in the range of 20–60 kHz with an additional
1 percent of tCK (AVG) as a long-term jitter component; however, the spread-spectrum may not
use a clock rate below tCK (AVG) MIN.
12. The clock’s tCH (AVG) and tCL (AVG) are the average half clock period over any 200 consecutive
clocks and is the smallest clock half period allowed, with the exception of a deviation due to
clock jitter. Input clock jitter is allowed provided it does not exceed values specifi ed and must be
of a random Gaussian distribution in nature.
13. The period jitter (tJITPER) is the maximum deviation in the clock period from the average or
nominal clock. It is allowed in either the positive or negative direction.
14. tCH(ABS) is the absolute instantaneous clock high pulse width as measured from one rising
edge to the following falling edge.
15. tCL(ABS) is the absolute instantaneous clock low pulse width as measured from one falling
edge to the following rising edge.
16. The cycle-to-cycle jitter (tJITCC) is the amount the clock period can deviate from one cycle to the
next. It is important to keep cycle-to-cycle jitter at a minimum during the DLL locking time.
17. The cumulative jitter error (tERRnPER), where n is the number of clocks between 2 and 50, is the
amount of clock time allowed to accumulate consecutively away from the average clock over n
number of clock cycles.
18. tDS (base) and tDH (base) values are for a single-ended 1 V/ns DQ slew rate and 2 V/ns
differential DQS, DQS# slew rate.
19. These parameters are measured from a data signal (DM, DQ0, DQ1, and so forth) transition
edge to its respective data strobe signal (DQS, DQS#) crossing.
20. The setup and hold times are listed converting the base specifi cation values (to which derating
tables apply) to VREF when the slew rate is 1 V/ns. These values, with a slew rate of 1 V/ns, are
for reference only.
21. When the device is operated with input clock jitter, this parameter needs to be derated by the
actual tJITPER of the input clock (output deratings are relative to the SDRAM input clock).
22. Single-ended signal parameter.
23. The DRAM output timing is aligned to the nominal or average clock. Most output parameters
must be derated by the actual jitter error when input clock jitter is present, even when within
specifi cation. This results in each parameter becoming larger. The following parameters are
required to be derated by subtracting tERR10PER (MAX): tDQSCK (MIN), tLZ (DQS)MIN, tLZ (DQ)
MIN, and tAON (MIN). The following parameters are required to be derated by subtracting
tERR10PER (MIN): tDQSCK (MAX), tHZ (MAX), tLZ (DQS)MAX, tLZ (DQ) MAX, and tAON (MAX). The
parameter tRPRE (MIN) is derated by subtracting tJITPER (MAX), while tRPRE (MAX) is derated by
subtracting tJITPER (MIN).
24. The maximum preamble is bound by tLZDQS (MAX).
25. These parameters are measured from a data strobe signal (DQS, DQS#) crossing to its
respective clock signal (CK, CK#) crossing. The specifi cation values are not affected by
the amount of clock jitter applied, as these are relative to the clock signal crossing. These
parameters should be met whether clock jitter is present.
26. The tDQSCK DLL_DIS parameter begins CL + AL - 1 cycles after the READ command.
27. The maximum postamble is bound by tHZDQS (MAX).
28. Commands requiring a locked DLL are: READ (and RDAP) and synchronous ODT commands.
In addition, after any change of latency tXPDLL, timing must be met.
29. tIS (base) and tIH (base) values are for a single-ended 1 V/ns control/command/ address slew
rate and 2 V/ns CK, CK# differential slew rate.
30. These parameters are measured from a command/address signal transition edge to its
respective clock (CK, CK#) signal crossing. The specifi cation values are not affected by the
amount of clock jitter applied as the setup and hold times are relative to the clock signal
crossing that latches the command/address. These parameters should be met whether clock
jitter is present.
31. For these parameters, the DDR3 SDRAM device supports tnPARAM (nCK) = RU(tPARAM [ns]/tCK[AVG] [ns]),
assuming all input clock jitter specifi cations are satisfi ed. For example, the device will support
tnRP (nCK) = RU(tRP/tCK[AVG]) if all input clock jitter specifi cations are met. This means for DDR3-800
6-6-6, of which tRP = 15ns, the device will support tnRP = RU(tRP/tCK[AVG]) = 6 as long as the input
clock jitter specifi cations are met. That is, the PRECHARGE command at T0 and the ACTIVATE
command at T0 + 6 are valid even if six clocks are less than 15ns due to input clock jitter.
32. During READs and WRITEs with auto precharge, the DDR3 SDRAM will hold off the internal
PRECHARGE command until tRAS (MIN) has been satisfi ed.
33. When operating in DLL disable mode, the greater of 4CK or 15ns is satisfi ed for tWR.
34. The start of the write recovery time is defi ned as follows:
– For BL8 (fi xed by MRS and OTF): Rising clock edge four clock cycles after WL
– For BC4 (OTF): Rising clock edge four clock cycles after WL
– For BC4 (fi xed by MRS): Rising clock edge two clock cycles after WL
35. RESET# should be LOW as soon as power starts to ramp to ensure the outputs are in High-Z.
Until RESET# is LOW, the outputs are at risk of driving and could result in excessive current,
depending on bus activity.
36. The refresh period is 64ms. This equates to an average refresh rate of 7.8125s. However, nine
REFRESH commands must be asserted at least once every 70.3s.
37. Although CKE is allowed to be registered LOW after a REFRESH command when tREFPDEN
(MIN) is satisfi ed, there are cases where additional time such as tXPDLL (MIN) is required.
38. ODT turn-on time MIN is when the device leaves High-Z and ODT resistance begins to turn on.
ODT turn-on time maximum is when the ODT resistance is
fully on.
39. Half-clock output parameters must be derated by the actual tERR10PER and tJITDTY when input
clock jitter is present. This results in each parameter becoming larger. The parameters tADC
(MIN) and tAOF (MIN) are each required to be derated by subtracting both tERR10PER (MAX)
and tJITDTY (MAX). The parameters tADC (MAX) and tAOF (MAX) are required to be derated by
subtracting both tERR10PER (MAX) and tJITDTY (MAX).
40. ODT turn-off time minimum is when the device starts to turn off ODT resistance. ODT turn-off
time maximum is when the DRAM buffer is in High-Z. This output load is used for ODT timings.
41. Pulse width of a input signal is defi ned as the width between the fi rst crossing of VREF(DC) and
the consecutive crossing of VREF(DC).
42. Should the clock rate be larger than tRFC (MIN), an AUTO REFRESH command should have at
least one NOP command between it and another AUTO REFRESH command. Additionally, if
the clock rate is slower than 40ns (25 MHz), all REFRESH commands should be followed by a
PRECHARGE ALL command.