Selecting the Memory Device

The Fabric DDR subsystem supports DDR3, DDR3L, DDR4, and LPDDR3 memory devices.

The memory that is used with the system depends on the application requirements. No single memory device can fulfill all system requirements; therefore, the trade-offs associated with each memory type must be considered for a balanced design.

Consider the following factors while selecting the memory device:

The following table lists the memory parameters for DDR3, DDR4, and LPDDR3 memory devices. Based on the system requirements (bandwidth, speed, bus width, density, and cost), the appropriate memory device is selected.

Table 1. Memory Selection Parameters
Parameter DDR3 DDR3L DDR4 LPDDR3
DDR clock 666 666 800 666
Data width (in bits) 16, 32, 64 16, 32, 64 16, 32, 64 16, 32
Burst length (in bytes) 8 8 8 8
Number of banks 8 8 8,16 8
Density 512 Mb–8192 Mb 512 Mb–8192 Mb 2 Gb–16 Gb 32 Gb
I/O standard SSTL-15 Class I, II SSTL-135 Class I, II POD-12 Class I, II* HSUL-12
Note: HSTL_12 IO standard is used for DDR4 address, command, and control signals.