PolarFire Board Design Recommendations

The GPIO and HSIO of PolarFire devices support various memory interfaces.

The following table lists the various types of memories supported in PolarFire devices.

Table 1. DDR3, and DDR4 Parameters
Parameter DDR3 LPDDR3 DDR3L DDR4
VDDIO 1.5 V 1.2 V 1.35 V 1.2 V
VTT, VREF 0.75 V 0.6 V 0.675 V 0.6 V
Clock, Address, and Command (CAC) Layout Daisy Chained 
(Fly-by) Point to point Daisy Chained

(Fly-by)

Daisy Chained (Fly-by)
Data Strobe Differential Differential Differential Differential
ODT Dynamic Dynamic Dynamic Dynamic
Match Addr/CMD/Ctrl to Clock Tightly Yes Yes Yes Yes
Match DQ/DM/DQS Tightly Yes Yes Yes Yes
Match DQS to Clock Loosely Not Required Not Required Not Required Not Required
I/O Standard SSTL_15 HSUL-12 SSTL_135 POD-12*
RZQ 240_1% 240_1% 240_1% 240_1%

* HSTL_12 IO standard is used for DDR4 address, command, and control signals.

For more information on DDR memories, see the following documents: