SPRAD06C March   2022  – March 2025 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM62L

1.   1
2.   Abstract
3.   Trademarks
4. 1Overview
   1. 1.1 Board Designs Supported
   2. 1.2 General Board Layout Guidelines
   3. 1.3 PCB Stack-Up
   4. 1.4 Bypass Capacitors
      1. 1.4.1 Bulk Bypass Capacitors
      2. 1.4.2 High-Speed Bypass Capacitors
      3. 1.4.3 Return Current Bypass Capacitors
   5. 1.5 Velocity Compensation
5. 2DDR4 Board Design and Layout Guidance
   1. 2.1  DDR4 Introduction
   2. 2.2  DDR4 Device Implementations Supported
   3. 2.3  DDR4 Interface Schematics
      1. 2.3.1 DDR4 Implementation Using 16-Bit SDRAM Devices
      2. 2.3.2 DDR4 Implementation Using 8-Bit SDRAM Devices
   4. 2.4  Compatible JEDEC DDR4 Devices
   5. 2.5  Placement
   6. 2.6  DDR4 Keepout Region
   7. 2.7  DBI
   8. 2.8  VPP
   9. 2.9  Net Classes
   10. 2.10 DDR4 Signal Termination
   11. 2.11 VREF Routing
   12. 2.12 VTT
   13. 2.13 POD Interconnect
   14. 2.14 CK and ADDR_CTRL Topologies and Routing Guidance
   15. 2.15 Data Group Topologies and Routing Guidance
   16. 2.16 CK and ADDR_CTRL Routing Specification
       1. 2.16.1 CACLM - Clock Address Control Longest Manhattan Distance
       2. 2.16.2 CK and ADDR_CTRL Routing Limits
   17. 2.17 Data Group Routing Specification
       1. 2.17.1 DQLM - DQ Longest Manhattan Distance
       2. 2.17.2 Data Group Routing Limits
   18. 2.18 Bit Swapping
       1. 2.18.1 Data Bit Swapping
       2. 2.18.2 Address and Control Bit Swapping
6. 3LPDDR4 Board Design and Layout Guidance
   1. 3.1  LPDDR4 Introduction
   2. 3.2  LPDDR4 Device Implementations Supported
   3. 3.3  LPDDR4 Interface Schematics
   4. 3.4  Compatible JEDEC LPDDR4 Devices
   5. 3.5  Placement
   6. 3.6  LPDDR4 Keepout Region
   7. 3.7  LPDDR4 DBI
   8. 3.8  Net Classes
   9. 3.9  LPDDR4 Signal Termination
   10. 3.10 LPDDR4 VREF Routing
   11. 3.11 LPDDR4 VTT
   12. 3.12 CK0 and ADDR_CTRL Topologies
   13. 3.13 Data Group Topologies
   14. 3.14 CK0 and ADDR_CTRL Routing Specification
   15. 3.15 Data Group Routing Specification
   16. 3.16 Byte and Bit Swapping
7. 4LPDDR4 Board Design Simulations
   1. 4.1 Board Model Extraction
   2. 4.2 Board-Model Validation
   3. 4.3 S-Parameter Inspection
   4. 4.4 Time Domain Reflectometry (TDR) Analysis
   5. 4.5 System Level Simulation
      1. 4.5.1 Simulation Setup
      2. 4.5.2 Simulation Parameters
      3. 4.5.3 Simulation Targets
         1. 4.5.3.1 Eye Quality
         2. 4.5.3.2 Delay Report
         3. 4.5.3.3 Mask Report
   6. 4.6 Design Example
      1. 4.6.1 Stack-Up
      2. 4.6.2 Routing
      3. 4.6.3 Model Verification
      4. 4.6.4 Simulation Results
8. 5Additional Information: Package Delays
9. 6Summary
10. 7References
11. 8Revision History

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