EP3SL150F780I3N Altera, EP3SL150F780I3N Datasheet - Page 98

• Manufacturer Part Number: EP3SL150F780I3N
• Description: Stratix III
• Manufacturer: Altera

Conclusion
Conclusion
4–24
Stratix III Device Handbook, Volume 1
f
Power-Up Conditions and Memory Initialization
M9K and M144K memory block outputs power up to zero (cleared),
regardless of whether the output registers are used or bypassed. MLABs
power up to zero if output registers are used and power up reading the
memory contents if output registers are not used. However, the actual
RAM cells power up to an unknown state. Therefore, after power-up, if
an address is read before being written, the output from the read
operation is undefined because the contents are not initialized.
All memory blocks support initialization via an MIF file (.mif). You can
create MIF files in the Quartus II software and specify their use with the
RAM MegaWizard when instantiating a memory in your design. Even if
a memory is pre-initialized (for example, by a .mif file), it still powers up
with its outputs cleared.
For more information on MIF files, refer to the
Guide
Power Management
Stratix III memory block clock-enables allow you to control clocking of
each memory block to reduce AC power consumption. Use the
read-enable signal to ensure that read operations only occur when you
need them to. If your design does not require read-during-write, you can
reduce your power consumption by de-asserting the read-enable signal
during write operations, or any period when no memory operations
occur.
The Quartus II software automatically places any unused memory blocks
in low power mode to reduce static power.
The Stratix III TriMatrix embedded memory structure provides three
different on-chip RAM block sizes to address your design needs. All
memory blocks are fully customizable and can be cascaded to implement
wider or deeper memories with minimal speed penalty.
You can independently configure each embedded memory block to be a
single- or dual-port RAM, FIFO, ROM, or shift register via the Quartus II
MegaWizard software.
as well as the
Quartus II
Handbook.
RAM Megafunction User
Altera Corporation
November 2007