The GPIO and HSIO of PolarFire devices support various memory interfaces.
The following table lists the various types of memories supported in PolarFire devices.
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: