W3H32M72E-XSBX Datasheet, PDF (9/30 Pages) White Electronic Designs Corporation – 32M x 72 DDR2 SDRAM 208 PBGA Multi-Chip Package

White Electronic Designs
W3H32M72E-XSBX
PRELIMINARY*
NOTES:
1. Applying power; if CKE is maintained below 0.2 x VCCQ, outputs remain disabled.
To guarantee RTT (ODT resistance) is off, VREF must be valid and a low level must
be applied to the ODT ball (all other inputs may be undefined, I/Os and outputs
must be less than VCCQ during voltage ramp time to avoid DDR2 SDRAM device
latch-up). At least one of the following two sets of conditions (A or B) must be
met to obtain a stable supply state (stable supply defined as VCC, VCCQ,VREF, and
VTT are between their minimum and maximum values as stated in DC Operating
Conditions table):
A. (single power source) The VCC voltage ramp from 300mV to VCC (MIN) must
take no longer than 200ms; during the VCC voltage ramp, |VCC - VCCQ| ≤ 0.3V.
Once supply voltage ramping is complete (when VCCQ crosses VCC (MIN), DC
Operating Conditions table specifications apply.
• VCC, VCCQ are driven from a single power converter output
• VTT is limited to 0.95V MAX
• VREF tracks VCCQ/2; VREF must be within ±0.3V with respect to VCCQ/2 during
supply ramp time.
• VCCQ ≥ VREF at all times
B. (multiple power sources) VCC ≥ VCCQ must be maintained during supply voltage
ramping, for both AC and DC levels, until supply voltage ramping completes
(VCCQ crosses VCC [MIN]). Once supply voltage ramping is complete, DC
Operating Conditions table specifications apply.
• Apply VCC before or at the same time as VCCQ; VCC voltage ramp time must
be ≤ 200ms from when VCC ramps from 300mV to VCC (MIN)
• Apply VCCQ before or at the same time as VTT; the VCCQ voltage ramp time
from when VCC (MIN) is achieved to when VCCQ (MIN) is achieved must be ≤
500ms; while VCC is ramping, current can be supplied from VCC through the
device to VCCQ
• VREF must track VCCQ/2, VREF must be within ±0.3V with respect to VCCQ/2
during supply ramp time; VCCQ ≥ VREF must be met at all times
• Apply VTT; The VTT voltage ramp time from when VCCQ (MIN) is achieved to
when VTT (MIN) is achieved must be no greater than 500ms
2. For a minimum of 200µs after stable power and clock (CK, CK#), apply NOP or
DESELECT commands and take CKE HIGH.
3. Wait a minimum of 400ns, then issue a PRECHARGE ALL command/
4. Issue an LOAD MODE command to the EMR(2). (To issue an EMR(2) command,
provide LOW to BA0, provide HIGH to BA1.)
5. Issue a LOAD MODE command to the EMR(3). (To issue an EMR(3) command,
provide HIGH to BA0 and BA1.)
6. Issue an LOAD MODE command to the EMR to enable DLL. To issue a DLL
ENABLE command, provide LOW to BA1 and A0, provide HIGH to BA0. Bits E7,
E8, and E9 can be set to “0” or “1”; Micron recommends setting them to “0.”
7. Issue a LOAD MODE command for DLL RESET. 200 cycles of clock input is
required to lock the DLL. (To issue a DLL RESET, provide HIGH to A8 and provide
LOW to BA1, and BA0.) CKE must be HIGH the entire time.
8. Issue PRECHARGE ALL command.
9. Issue two or more REFRESH commands, followed by a dummy WRITE.
10. Issue a LOAD MODE command with LOW to A8 to initialize device operation (i.e.,
to program operating parameters without resetting the DLL).
11. Issue a LOAD MODE command to the EMR to enable OCD default by setting bits
E7, E8, and E9 to “1,” and then setting all other desired parameters.
12. Issue a LOAD MODE command to the EMR to enable OCD exit by setting bits E7,
E8, and E9 to “0,” and then setting all other desired parameters.
13. Issue a LOAD MODE command with LOW to A8 to initialize device operation (i.e.,
to program operating parameters without resetting the DLL).
14. Issue a LOAD MODE command to the EMR to enable OCD default by setting bits
E7,E8, and E9 to “1,” and then setting all other desired parameters.
15. Issue a LOAD MODE command to the EMR to enable OCD exit by setting bits E7,
E8, and E9 to “0,” and then setting all other desired parameters.
The DDR2 SDRAM is now initialized and ready for normal operation 200 clocks after
DLL RESET (in step 7).
White Electronic Designs Corp. reserves the right to change products or specifications without notice.
February 2006
Rev. 2
9
White Electronic Designs Corporation • [phone] • www.wedc.com