Intel® 820E Chipset
R
Design Guide 7
4.8. Decoupling Recommendation for CK133 and DRCG .................................................174
4.9. DRCG Frequency Selection and the DRCG+............................................................. 175
4.9.1. DRCG Frequency Selection Table and Jitter Specification....................... 175
4.9.2. DRCG+ Frequency Selection Schematic.................................................. 176
5. System Manufacturing............................................................................................................. 177
5.1. Stack-Up Requirement................................................................................................ 177
5.1.1. PCB Materials ...........................................................................................177
5.1.2. Design Process......................................................................................... 178
5.1.3. Test Coupon Design Guidelines................................................................ 178
5.1.4. Recommended Stack-Up.......................................................................... 179
5.1.5. Inner-Layer Routing...................................................................................179
5.1.6. Impedance Calculation Tools.................................................................... 180
5.1.7. Testing Board Impedance......................................................................... 181
5.1.8. Board Impedance/Stack-up Summary ......................................................181
6. System Design Considerations................................................................................................ 183
6.1. Power Delivery.............................................................................................................183
6.1.1. Terminology and Definitions...................................................................... 183
6.1.2. Power Delivery of Intel® 820E Chipset Customer Reference Board......... 184
6.1.3. ICH2 1.8 V / 3.3 V Power Sequencing...................................................... 188
6.1.5. Excessive Power Consumption by 64/72-Mbit RDRAM............................ 190
6.1.5.1. Option 1: Reduce the Clock Frequency During Initialization ........190
6.1.5.2. Option 2: Increase the Current Capability of the 2.5 V Voltage
Regulator...................................................................................... 191
6.2. ICH2 Power Plane Split............................................................................................... 192
6.3. Thermal Design Power................................................................................................ 193
6.4. Glue Chip 3 (Intel® 820E Chipset Glue Chip).............................................................. 193
Appendix A: Reference Design Schematics (Uniprocessor) ...........................................................................195