eorex
EM428M1644RTA
Pin Description (Simplified)
Pin
Name
Function
(System Clock)
Clock input active on the Positive rising edge except for DQ and
DM are active on both edge of the DQS.
CLK and /CLK are differential clock inputs.
(Chip Select)
45,46
CLK,/CLK
/CS enables the command decoder when ”L” and disable the
command decoder when “H”.The new command are over-
Looked when the command decoder is disabled but previous
operation will still continue.
24
/CS
(Clock Enable)
Activates the CLK when “H” and deactivates when “L”.
When deactivate the clock,CKE low signifies the power down or
self refresh mode.
44
CKE
(Address)
Row address (A0 to A11) and Calumn address (CA0 to CA8) are
multiplexed on the same pin.
28~32,35~41
A0~A11
CA10 defines auto precharge at Calumn address.
(Bank Address)
26, 27
23
BA0, BA1
/RAS
Selects which bank is to be active.
(Row Address Strobe)
Latches Row Addresses on the positive rising edge of the CLK with
/RAS “L”. Enables row access & pre-charge.
(Column Address Strobe)
22
/CAS
Latches Column Addresses on the positive rising edge of the CLK
with /CAS low. Enables column access.
(Write Enable)
21
/WE
Latches Column Addresses on the positive rising edge of the CLK
with /CAS low. Enables column access.
(Data Input/Output)
16/51
20/47
LDQS/UDQS
LDM/UDM
Data Inputs and Outputs are synchronized with both edge of DQS.
(Data Input/Output Mask)
DM controls data inputs.LDM corresponds to the data on
DQ0~DQ7.UDM corresponds to the data on DQ8~DQ15.
2, 4, 5, 7, 8, 10,
11, 13, 54, 56, 57,
59, 60, 62, 63, 65
1,18,33/
(Data Input/Output)
DQ0~DQ15
Data inputs and outputs are multiplexed on the same pin.
(Power Supply/Ground)
VDD/VSS
VDDQ/VSSQ
NC/RFU
VREF
34,48,66
VDD and VSS are power supply pins for internal circuits.
(Power Supply/Ground)
3, 9, 15, 55.61/
6, 12, 52, 58,64
14,17,19,25,42,
43,50,53
VDDQ and VSSQ are power supply pins for the output buffers.
(No Connection/Reserved for Future Use)
This pin is recommended to be left No Connection on the device.
(Input)
49
SSTL-2 Reference voltage for input buffer.
Apr. 2007
www.eorex.com
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EOREX [ EOREX CORPORATION ]
