ESMT
M12L64164A
Elite Semiconductor Memory Technology Inc.
Publication Date: May 2008
Revision: 3.3
4/46
FUNCTIONAL BLOCK DIAGRAM
PIN FUNCTION DESCRIPTION
PIN NAME
INPUT
FUNCTION
CLK
System Clock
Active on the positive going edge to sample all inputs
CS
Chip Select
Disables or enables device operation by masking or enabling all
inputs except CLK , CKE and L(U)DQM
CKE
Clock Enable
Masks system clock to freeze operation from the next clock cycle.
CKE should be enabled at least one cycle prior new command.
Disable input buffers for power down in standby.
A0 ~ A11
Address
Row / column address are multiplexed on the same pins.
Row address : RA0~RA11, column address : CA0~CA7
BA1 , BA0
Bank Select Address
Selects bank to be activated during row address latch time.
Selects bank for read / write during column address latch time.
RAS
Row Address Strobe
Latches row addresses on the positive going edge of the CLK with
RAS low.
Enables row access & precharge.
CAS
Column Address Strobe
Latches column address on the positive going edge of the CLK with
CAS low.
Enables column access.
WE
Write Enable
Enables write operation and row precharge.
Latches data in starting from CAS , WE active.
L(U)DQM
Data Input / Output Mask
Makes data output Hi-Z, t
SHZ
after the clock and masks the output.
Blocks data input when L(U)DQM active.
DQ0 ~ DQ15
Data Input / Output
Data inputs / outputs are multiplexed on the same pins.
VDD / VSS
Power Supply / Ground
Power and ground for the input buffers and the core logic.
VDDQ / VSSQ Data Output Power / Ground
Isolated power supply and ground for the output buffers to provide
improved noise immunity.
NC
No Connection
This pin is recommended to be left No Connection on the device.
L(U)DQM
DQ
Mode
Register
Control Logic
Column
Address
Buffer
&
Refresh
Counter
Row
Address
Buffer
&
Refresh
Counter
Bank D
Row Decode
r
Bank A
Bank B
Bank C
Sense Amplifier
Column Decoder
Data Control Circuit
Latch Circuit
Input & Out
put
Buf
fer
Address
Clock
Generator
CLK
CKE
Command Deco
der
CS
RAS
CAS
WE