AMD AMD-K6-2/400 User Guide - Page 339

Measuring Case Temperature, 17.3 Layout and Airflow Considerations, Voltage Regulator

Page 339 highlights

23542A/0-September 2000 Preliminary Information AMD-K6™-2E+ Embedded Processor Data Sheet 17.2 Measuring Case Temperature The processor case temperature is measured to ensure that the thermal solution meets the processor's operational specification. This temperature should be measured on the top center of the package, where most of the heat is dissipated. Figure 116 shows the correct location for measuring the case temperature. The tip of the thermocouple should be secured to the package surface with a small amount of thermally conductive epoxy. It is also recommended to secure a second location along the thermocouple to avoid any movement during testing. If a heatsink is installed while measuring, the thermocouple must be installed into the heatsink via a small hole drilled through the heatsink base (for example, 1/16 of an inch). Secure the thermocouple to the base of the heatsink by filling the small hole with thermal epoxy, allowing the tip of the thermocouple to protrude the epoxy and touch the top of the processor case. Thermally Conductive Epoxy Thermocouple Figure 116. Measuring Case Temperature 17.3 Layout and Airflow Considerations Voltage Regulator A voltage regulator is required to support the lower voltage (3.3 V and lower) to the processor. In most applications, the voltage regulator is designed with power transistors. As a result, additional heatsinks are required to dissipate the heat from the power transistors. Figure 117 on page 318 shows the Chapter 17 Thermal Design 317

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
  • 213
  • 214
  • 215
  • 216
  • 217
  • 218
  • 219
  • 220
  • 221
  • 222
  • 223
  • 224
  • 225
  • 226
  • 227
  • 228
  • 229
  • 230
  • 231
  • 232
  • 233
  • 234
  • 235
  • 236
  • 237
  • 238
  • 239
  • 240
  • 241
  • 242
  • 243
  • 244
  • 245
  • 246
  • 247
  • 248
  • 249
  • 250
  • 251
  • 252
  • 253
  • 254
  • 255
  • 256
  • 257
  • 258
  • 259
  • 260
  • 261
  • 262
  • 263
  • 264
  • 265
  • 266
  • 267
  • 268
  • 269
  • 270
  • 271
  • 272
  • 273
  • 274
  • 275
  • 276
  • 277
  • 278
  • 279
  • 280
  • 281
  • 282
  • 283
  • 284
  • 285
  • 286
  • 287
  • 288
  • 289
  • 290
  • 291
  • 292
  • 293
  • 294
  • 295
  • 296
  • 297
  • 298
  • 299
  • 300
  • 301
  • 302
  • 303
  • 304
  • 305
  • 306
  • 307
  • 308
  • 309
  • 310
  • 311
  • 312
  • 313
  • 314
  • 315
  • 316
  • 317
  • 318
  • 319
  • 320
  • 321
  • 322
  • 323
  • 324
  • 325
  • 326
  • 327
  • 328
  • 329
  • 330
  • 331
  • 332
  • 333
  • 334
  • 335
  • 336
  • 337
  • 338
  • 339
  • 340
  • 341
  • 342
  • 343
  • 344
  • 345
  • 346
  • 347
  • 348
  • 349
  • 350
  • 351
  • 352
  • 353
  • 354
  • 355
  • 356
  • 357
  • 358
  • 359
  • 360
  • 361
  • 362
  • 363
  • 364
  • 365
  • 366
  • 367
  • 368

Chapter 17
Thermal Design
317
23542A/0—September 2000
AMD-K6™-2E+ Embedded Processor Data Sheet
Preliminary Information
17.2
Measuring Case Temperature
The processor case temperature is measured to ensure that the
thermal solution meets the processor’s operational
specification. This temperature should be measured on the top
center of the package, where most of the heat is dissipated.
Figure 116 shows the correct location for measuring the case
temperature. The tip of the thermocouple should be secured to
the package surface with a small amount of thermally
conductive epoxy. It is also recommended to secure a second
location along the thermocouple to avoid any movement during
testing.
If a heatsink is installed while measuring, the thermocouple
must be installed into the heatsink via a small hole drilled
through the heatsink base (for example, 1/16 of an inch). Secure
the thermocouple to the base of the heatsink by filling the
small hole with thermal epoxy, allowing the tip of the
thermocouple to protrude the epoxy and touch the top of the
processor case.
Figure 116.
Measuring Case Temperature
17.3
Layout and Airflow Considerations
Voltage Regulator
A voltage regulator is required to support the lower voltage
(3.3 V and lower) to the processor. In most applications, the
voltage regulator is designed with power transistors. As a
result, additional heatsinks are required to dissipate the heat
from the power transistors. Figure 117 on page 318 shows the
Thermocouple
Thermally Conductive Epoxy