Memory; Pipelined Zbtram; Table 2: Zbtram Sizes - Sundance Spas SMT398 User Manual

Version 1.1.1

Memory

Pipelined ZBTRAM

Up to 16Mbytes of pipeline ZBT memory is provided with direct access by the FPGA.
The ZBTRAM is designed to sustain 100% bus bandwidth by eliminating turnaround
cycle when there is transition from Read to Write, or vice versa.
This device is well suited for SDR applications that experience frequent bus
turnarounds, need to operate on small data chunks (especially one-word chunks),
and need to operate at higher frequencies than permitted by the flow-through
version.
The memory is split into 4 independent 16-bit-wide Banks.
All three chip enables are available on each bank for simple depth expansion with no
data contention.
Each bank is composed of one chip, available in 4 different sizes as presented in

Table 2: ZBTRAM sizes:

For more complete information, please read:
General Information on how to choose your memory type according to your
application
For the parts datasheet, please read:
ZBTRAM datasheets
Chips parts and densities are shown in the table below.
ZBTRAM part
number
K7N401801A
K7N801801M
K7N161801A
K7N321801M
Table 2: ZBTRAM sizes
The total available ZBT RAM on the board is therefore 2 MBytes, 4 MBytes, 8
MBytes, or 16 MBytes
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Size in Size in
bits Bytes
4Mb 512kBytes 256kx18
8Mb 1MBytes
16Mb 2MBytes
32Mb 4MBytes
Actual Amount
Memory of
size memory
per board
2 MBytes
512kx18 4 MBytes
1Mx18 8 MBytes
2Mx18 16
MBytes
SMT398 User Manual