PCB Design Guidelines: Agilex™ 3 FPGAs and SoCs

ID 853726
Date 8/20/2025
Public
Document Table of Contents

6.3.1. LPDDR4 Memory Down Topology (Up to 32-bits Interface)

LPDDR4 memory down supports single rank and dual-rank configurations up to 32 bits. There are four DRAM interface signal groupings—data group, command-address group, control group, and clock group.
Figure 32. Stripline Routing for Data, CA, CTRL, and Clock Signals Point-to-Point TopologyThis figure shows the stripline routing for inner pins.


Figure 33. Stripline Routing for Reset SignalsThis figure shows the Reset signal routing topology. Altera recommends using 1.0 KΩ pull-down resistor for Reset signal termination


Figure 34. Microstrip Routing on the Outer Layer for Data Signals Point-to-Point TopologyThis figure shows the microstrip routing for the edge pins of BGA per byte.


Figure 35. Stripline Routing for CA, CLK, and CTRL Daisy-Chain and T-Line TopologyThis figure shows the daisy-chain and T-Line connections topology for CA, CLK, and CTRL signals for LPDDR4.