104
www.xilinx.com
ML365 Virtex-II Pro QDR II SRAM Mem. Board
1-800-255-7778
UG066 (v1.0) June 29, 2004
Appendix 3:
Memory Board Schematics and Characterization Results
R
Characterization Results
Long-Term Runs
The significant long-term runs are as follows:
•
ML365 Serial 10 ran 215 MHz for 48 hours with no errors
•
ML365 Serial 11 ran overnight at 240 MHz and 235 MHz with bit errors (one or more)
•
ML635 Serial 11 ran 230 MHz for 144 hours with no errors
Corners Results Matrix
The measurements made on eleven boards are listed in
. The slowest performance
numbers are:
6C: 210 MHz
6C prod: 237 MHz
7C: 242 MHz
7C prod: 275 MHz
Observations
Memory device V
ref
levels are very important. They have been adjusted for each single test,
and were set up at the optimal value for the memory interface under test. At optimal
voltage (1.800V), it appears that 0.900V was, in almost all cases, the optimal setting;
variations of 1.8V required significant adjustments of V
ref
to obtain the best performance
(+5% tests can require a +10% increase of V
ref
).
Table 3-1:
Corners Results Measurements
Ambient
Temp
V
CC
Bd 3
Bd 9
Bd 10
Bd 8
Bd9A Bd 11
Bd 4
Bd 7
Bd 6
Bd B Bd C
-6 Slow
-6 Prod
-7 Prod
-7 Slow
25 Degree C
Nom
218
219
223
217
223
247
260
271
284
248
254
Nom -5%
216
218
219
215
219
245
257
267
271
246
253
Nom +5%
219
220
224
218
224
248
263
266
285
249
256
70 Degrees C
Nom
213
219
216
212
215
241
257
263
280
243
251
Nom -5%
212
216
214
210
214
237
254
262
275
242
250
Nom +5%
214
220
217
213
215
243
258
263
282
245
252
0 Degrees C
Nom
228
230
231
226
229
266
278
273
292
264
268
Nom -5%
224
229
230
226
228
265
278
272
290
263
268
Nom +5%
230
231
232
228
230
267
279
291
302
266
272
Product Not Recommended for New Designs