MicroBlaze Development Kit Spartan-3E 1600 Edition User Guide 105
UG257 (v1.1) December 5, 2007 www.xilinx.com
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Chapter 13

DDR SDRAM
The MicroBlaze Development Kit board includes a 512 Mbit (32Mx 16) Micron Technology
DDR SDRAM (MT46V32M16) with a 16-bit data interface, as shown in Figure 13-1. All
DDR SDRAM interface pins connect to the FPGA’s I/O Bank 3 on the FPGA. I/O Bank 3
and the DDR SDRAM are both powered by 2.5V, generated by an LTC3412 regulator from
the board’s 5V supply input. The 1.25V reference voltage, common to the FPGA and DDR
SDRAM, is generated using a resistor voltage divider from the 2.5V rail.
All DDR SDRAM interface signals are terminated.
Figure 13-1: FPGA Interface to Micron 512 Mbit DDR SDRAM
UG257_13_01_060806
See Table SD_A<12:0>
(C1)
Spartan-3E FPGA
SD_DQ<15:0>
SD_BA<1:0>
SD_RAS
A[12:0]
BA[1:0]
DQ[15:0]
RAS#
Micron 512 Mb DDR SDRAM
SD_CAS
SD_WE
SD_CK_P
SD_CK_N
SD_CKE
SD_CS
SD_LDM
SD_UDM
SD_UDQS
SD_LDQS
SD_CK_FB
CAS#
WE#
UQM
LQM
UDQS
LDQS
CS#
CK
CK#
CKE
See Table
See Table
(C2)
(D1)
(J1)
(J2)
(G3)
(L6)
(K4)
(K3)
(J4)
(J5)(B9) GCLK9
VREF
VCCO_3
5.0V
LTC3412
VREF
VDD
VDDQ
2.5V
1.25V

MT46V32M16

(32Mx16)