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Intel®852GM Chipset Platform Design Guide 5
7.3.3.3. Clock Package Length Table ..........................................................89
7.3.3.4. Clock Routing Example...................................................................89
7.3.3.4.1. Clock Routing Updates for “DDP Stacked” Memory
Device Support .............................................................90
7.3.4. Data Signals – SDQ[64:0], SDM[7:0], SDQS[7:0]..........................................90
7.3.4.1. Data Bus Topology..........................................................................92
7.3.4.2. SDQS to Clock Length Matching Requirements.............................94
7.3.4.3. Data to Strobe Length Matching Requirements..............................95
7.3.4.4. SDQ to SDQS Mapping ..................................................................96
7.3.4.5. SDQ/SDQS Signal Package Lengths .............................................98
7.3.4.6. DDR Data Routing Example .........................................................100
7.3.5. Control Signals – SCKE[3:0], SCS#[3:0] .....................................................100
7.3.5.1. Control Signal Topology................................................................101
7.3.5.2. Control Signal Routing Guidelines................................................102
7.3.5.3. Control to Clock Length Matching Requirements .........................103
7.3.5.4. DDR Control Routing Example .....................................................105
7.3.5.5. Control Group Package Length Table ..........................................106
7.3.6. Command Signals – SMA[12:6,3,0], SBA[1:0], SRAS#, SCAS#, SWE#.....106
7.3.6.1. Command Topology 1...................................................................106
7.3.6.2. Command Topology 1 Routing Guidelines ...................................108
7.3.6.3. Command Topology 1 Length Matching Requirements ...............109
7.3.6.4. Command Topology 2...................................................................111
7.3.6.5. Command Topology 2 Routing Guidelines ...................................112
7.3.6.6. Command Topology 2 Length Matching Requirements ...............113
7.3.6.7. Command Topology 2 Routing Example ......................................115
7.3.6.8. Command Topology 3...................................................................116
7.3.6.9. Command Topology 3 Routing Guidelines ...................................117
7.3.6.10. Command Topology 3 Length Matching Requirements ...............118
7.3.6.11. Command Group Package Length Table .....................................120
7.3.7. CPC Signals – SMA[5,4,2,1], SMAB[5,4,2,1]...............................................121
7.3.7.1. CPC Signal Topology....................................................................122
7.3.7.2. CPC Signal Routing Guidelines ....................................................122
7.3.7.3. CPC to Clock Length Matching Requirements .............................123
7.3.7.4. CPC Group Package Length Table ..............................................125
7.3.8. Feedback – RCVENOUT#, RCVENIN#.......................................................125
7.4. System Memory Compensation...................................................................................125
7.5. SMVREF Generation ...................................................................................................125
7.6. DDR Power Delivery....................................................................................................125
7.7. External Thermal Sensor Based Throttling (ETS#) .....................................................126
7.7.1. ETS# Usage Model ......................................................................................126
7.7.2. ETS# Design Guidelines ..............................................................................126
7.7.3. Thermal Sensor Placement Guidelines .......................................................127
8. Integrated Graphics Display Port .............................................................................................129
8.1. Analog RGB/CRT Guidelines ......................................................................................129
8.1.1. RAMDAC/Display Interface..........................................................................129
8.1.2. Reference Resistor (REFSET).....................................................................129
8.1.3. RAMDAC Board Design Guidelines.............................................................130
8.1.4. RAMDAC Routing Guidelines ......................................................................131
8.1.5. DAC Power Requirements...........................................................................133
8.1.6. HSYNC and VSYNC Design Considerations...............................................134
8.1.7. DDC and I2C Design Considerations ..........................................................134
8.2. LVDS Transmitter Interface .........................................................................................134
8.2.1. Length Matching Constraints .......................................................................135