Block RAM and UltraRAM Comparison - Block RAM and UltraRAM Comparison - UG573

UltraScale Architecture Memory Resources User Guide (UG573)

Document ID: UG573
Release Date: 2025-11-18
Revision: 1.14 English

The following table shows a comparison of the block RAM and UltraRAM main features.

Table 1. Block RAM and UltraRAM Comparison
Feature	Block RAM	UltraRAM
Clocking	Two clocks	Single clock
Built-in FIFO	Yes	No
Data width	Configurable (1, 2, 4, 9, 18, 36, 72)	Fixed (72-bits)
Modes	SDP and TDP	Two ports, each can independently read or write (a superset of SDP)
ECC	64-bit SECDED Supported in 64-bit SDP only (one ECC decoder for port A and one ECC encoder for port B)	64-bit SECDED One set of complete ECC logic for each port to enable independent ECC operations (ECC encoder and decoder for both ports)
Cascade	Cascade output only (input cascade implemented via logic resources) Cascade within a single clock region	Cascade both input and output (with global address decoding) Cascade across clock regions in a column Cascade across several columns with minimal logic resources
Power savings	One mode via manual signal assertion	One mode via manual signal assertion