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Features
• Fully Synchronous to Positive Clock Edge
• Single 3.3V
±0.3V
Power Supply
• LVTTL Compatible with Multiplexed Address
• Programmable Burst Length (B/L) - 1, 2, 4, 8
or Full Page
• Programmable CAS Latency (C/L) - 2 or 3
• Data Mask (DQM) for Read / Write Masking
• Programmable Wrap Sequence
– Sequential (B/L = 1/2/4/8/full Page)
– Interleave (B/L = 1/2/4/8)
• Burst Read with Single-bit Write Operation
• All Inputs are Sampled at the Rising Edge of
the System Clock
• Auto Refresh and Self Refresh
• 4,096 Refresh Cycles / 64ms (15.625us)
EM488M3244VTB
256Mb (2M
×
4Bank
×
32) Synchronous DRAM
Description
The EM488M3244VTB is Synchronous Dynamic
Random Access Memory (SDRAM) organized as
2Meg words x 4 banks by 32 bits. All inputs and
outputs are synchronized with the positive edge of
the clock.
The 256Mb SDRAM uses synchronized pipelined
architecture to achieve high speed data transfer
rates and is designed to operate at 3.3V low power
memory system. It also provides auto refresh with
power saving / down mode. All inputs and outputs
voltage levels are compatible with LVTTL.
Available packages:TSOPII 86P 400mil.
Ordering Information
Part No
EM488M3244VTB-75F
EM488M3244VTB-7F
EM488M3244VTB-6F
EM488M3244VTB-75FE
EM488M3244VTB-7FE
EM488M3244VTB-6FE
Organization
8M X 32
8M X 32
8M X 32
8M X 32
8M X 32
8M X 32
Max. Freq
133MHz @CL3
143MHz @CL3
166MHz @CL3
133MHz @CL3
143MHz @CL3
166MHz @CL3
Package
86pin TSOP(ll)
86pin TSOP(ll)
86pin TSOP(ll)
86pin TSOP(ll)
86pin TSOP(ll)
86pin TSOP(ll)
Grade
Commercial
Commercial
Commercial
Extended
Extended
Extended
Pb
Free
Free
Free
Free
Free
Free
* EOREX reserves the right to change products or specification without notice.
Jul. 2006
1/17
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eorex
Pin Assignment
EM488M3244VTB
86pin TSOP-II / (400mil
×
875mil) / (0.5mm Pin pitch)
Jul. 2006
2/17
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Pin Description (Simplified)
Pin
68
20
Name
CLK
/CS
EM488M3244VTB
Function
(System Clock)
Master clock input (Active on the positive rising edge)
(Chip Select)
Selects chip when active
(Clock Enable)
Activates the CLK when “H” and deactivates when “L”.
CKE should be enabled at least one cycle prior to new
command. Disable input buffers for power down in standby.
(Address)
Row address (A0 to A11) is determined by A0 to A11 level at
the bank active command cycle CLK rising edge.
CA (CA0 to CA8) is determined by A0 to A8 level at the read or
write command cycle CLK rising edge.
And this column address becomes burst access start address.
A10 defines the pre-charge mode. When A10= High at the
pre-charge command cycle, all banks are pre-charged.
But when A10= Low at the pre-charge command cycle, only the
bank that is selected by BA0/BA1 is pre-charged.
(Bank Address)
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)
Latches Column Addresses on the positive rising edge of the
CLK with /CAS low. Enables column access.
(Write Enable)
Latches Column Addresses on the positive rising edge of the
CLK with /CAS low. Enables column access.
(Data Input/Output Mask)
DQM controls I/O buffers.
(Data Input/Output)
DQ pins have the same function as I/O pins on a conventional
DRAM.
(Power Supply/Ground)
V
DD
and V
SS
are power supply pins for internal circuits.
(Power Supply/Ground)
V
DDQ
and V
SSQ
are power supply pins for the output buffers.
(No Connection)
This pin is recommended to be left No Connection on the
device.
67
CKE
21,24~27,60~66
A0~A11
22, 23
19
BA0, BA1
/RAS
18
/CAS
17
16,28,59,71
2, 4, 5, 7, 8, 10,
11,13,31,33,34,36
,37,39,40,42,45,
47,48,50,51,53,
54,56,74,76,77,
79,80,82,83,85
1,15,29,43/
44,58,72,86
3,9,35,41,49,55,
75,81/6,12,32,38,
46,52,78,84
14,30,57,69,70,
73
/WE
DQM0~DQM3
DQ0~DQ31
V
DD
/V
SS
V
DDQ
/V
SSQ
NC
Jul. 2006
3/17
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Absolute Maximum Rating
Symbol
V
IN
, V
OUT
V
DD
, V
DDQ
T
OP
T
STG
P
D
Item
Input, Output Voltage
Power Supply Voltage
Operating Temperature Range
Storage Temperature Range
Power Dissipation
EM488M3244VTB
Rating
-0.3 ~ +4.6
-0.3 ~ +4.6
Commercial
0 ~ +70
Extended
-25 ~ +85
-55 ~ +150
1
Units
V
V
°C
°C
W
I
OS
Short Circuit Current
50
mA
Note:
Caution Exposing the device to stress above those listed in Absolute Maximum Ratings could
cause permanent damage. The device is not meant to be operated under conditions outside the
limits described in the operational section of this specification. Exposure to Absolute Maximum
Rating conditions for extended periods may affect device reliability.
Capacitance (V
CC
=3.3V, f=1MHz, T
A
=25°C)
Symbol
C
CLK
C
I
C
O
Parameter
Clock Capacitance
Input Capacitance for CLK, CKE, Address,
/CS, /RAS, /CAS, /WE, DQML, DQMU
Input/Output Capacitance
Min.
2.5
2.5
4.0
Typ.
Max.
4.0
5.0
6.5
Units
pF
pF
pF
Recommended DC Operating Conditions (T
A
=-25°C ~85°C)
Symbol
V
DD
V
DDQ
V
IH
Parameter
Power Supply Voltage
Power Supply Voltage (for I/O Buffer)
Input Logic High Voltage
Min.
3.0
3.0
2.0
-0.3
Typ.
3.3
3.3
Max.
3.6
3.6
V
DD
+0.3
0.8
Units
V
V
V
V
V
IL
Input Logic Low Voltage
Note:
* All voltages referred to V
SS
.
* V
IH
(max.) = 5.6V for pulse width 3ns
* V
IL
(min.) = -2.0V for pulse width 3ns
Jul. 2006
4/17
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Recommended DC Operating Conditions
Symbol
I
CC1
I
CC2P
I
CC2PS
I
CC2N
Parameter
Operating Current
(Note 1)
EM488M3244VTB
(V
DD
=3.3V±0.3V, T
A
=0°C ~70°C/T
A
=-25°C ~ +85°C for extended grade)
Test Conditions
Burst length=1,
t
RC
≥t
RC
(min.), I
OL
=0mA,
One bank active
CKE≤V
IL
(max.), t
CK
=15ns
CKE≤V
IL
(max.), t
CK
=
∞
CKE≥V
IL
(min.), t
CK
=15ns,
/CS≥V
IH
(min.)
Input signals are changed
one time during 30ns
CKE≥V
IL
(min.), t
CK
=
∞
,
Input signals are stable
CKE≤V
IL
(max.), t
CK
=15ns
CKE≤V
IL
(max.), t
CK
=
∞
CKE≥V
IL
(min.), t
CK
=15ns,
/CS≥V
IH
(min.)
Input signals are changed
one time during 30ns
CKE≥V
IL
(min.), t
CK
=
∞
,
Input signals are stable
t
CCD
≥2CLKs,
I
OL
=0mA
t
RC
≥t
RC
(min.)
CKE≤0.2V
3
Max.
125
3
3
30
Units
mA
mA
mA
mA
Precharge Standby Current in
Power Down Mode
Precharge Standby Current in
Non-power Down Mode
I
CC2NS
I
CC3P
I
CC3PS
I
CC3N
Active Standby Current in
Power Down Mode
20
5
5
45
mA
mA
mA
mA
Active Standby Current in
Non-power Down Mode
I
CC3NS
I
CC4
I
CC5
I
CC6
Operating Current (Burst
(Note 2)
Mode)
Refresh Current
(Note 3)
35
150
270
(Note 4)
mA
mA
mA
mA
Self Refresh Current
*All voltages referenced to V
SS
.
Note 1:
I
CC1
depends on output loading and cycle rates.
Specified values are obtained with the output open.
Input signals are changed only one time during t
CK
(min.)
Note 2:
I
CC4
depends on output loading and cycle rates.
Specified values are obtained with the output open.
Input signals are changed only one time during t
CK
(min.)
Note 3:
Input signals are changed only one time during t
CK
(min.)
Note 4:
Standard power version.
Recommended DC Operating Conditions (Continued)
Symbol
I
IL
I
OL
V
OH
V
OL
Jul. 2006
5/17
Parameter
Input Leakage Current
Output Leakage Current
High Level Output Voltage
Low Level Output Voltage
Test Conditions
0≤V
I
≤V
DDQ
, V
DDQ
=V
DD
All other pins not under test=0V
0≤V
O
≤V
DDQ
, D
OUT
is disabled
I
O
=-4mA
I
O
=+4mA
Min.
-0.5
-0.5
2.4
Typ.
Max.
+0.5
+0.5
0.4
Units
uA
uA
V
V
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