IS41C16105
IS41LV16105
1M x 16 (16-MBIT) DYNAMIC RAM
WITH FAST PAGE MODE
FEATURES
• TTL compatible inputs and outputs; tristate I/O
• Refresh Interval:
— 1,024 cycles/16 ms
• Refresh Mode:
—
RAS-Only, CAS-before-RAS
(CBR), and Hidden
• JEDEC standard pinout
• Single power supply:
— 5V ± 10% (IS41C16105)
— 3.3V ± 10% (IS41LV16105)
• Byte Write and Byte Read operation via two
CAS
• Extended Temperature Range -30
o
C to 85
o
C
• Industrail Temperature Range -40
o
C to 85
o
C
ISSI
DESCRIPTION
®
FEBRUARY 2000
The
ISSI
IS41C16105 and IS41LV16105 are 1,048,576 x
16-bit high-performance CMOS Dynamic Random Access Memo-
ries. Fast Page Mode allows 1,024 random accesses within a single
row with access cycle time as short as 20 ns per 16-bit word. The
Byte Write control, of upper and lower byte, makes the IS41C16105
ideal for use in 16-, 32-bit wide data bus systems.
These features make the IS41C16105 and IS41LV16105 ideally
suited for high-bandwidth graphics, digital signal processing, high-
performance computing systems, and peripheral applications.
The IS41C16105 and IS41LV16105 are packaged in a
42-pin 400-mil SOJ and 400-mil 44- (50-) pin TSOP (Type II).
KEY TIMING PARAMETERS
Parameter
Max.
RAS
Access Time (t
RAC
)
Max.
CAS
Access Time (t
CAC
)
Max. Column Address Access Time (t
AA
)
Min. Fast Page Mode Cycle Time (t
PC
)
Min. Read/Write Cycle Time (t
RC
)
-50
50
13
25
20
84
-60
60
15
30
25
104
Unit
ns
ns
ns
ns
ns
PIN CONFIGURATIONS
44(50)-Pin TSOP (Type II)
42-Pin SOJ
VCC
I/O0
I/O1
I/O2
I/O3
VCC
I/O4
I/O5
I/O6
I/O7
NC
NC
NC
WE
RAS
NC
NC
A0
A1
A2
A3
VCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
GND
I/O15
I/O14
I/O13
I/O12
GND
I/O11
I/O10
I/O9
I/O8
NC
NC
LCAS
UCAS
OE
A9
A8
A7
A6
A5
A4
GND
VCC
I/O0
I/O1
I/O2
I/O3
VCC
I/O4
I/O5
I/O6
I/O7
NC
NC
WE
RAS
NC
NC
A0
A1
A2
A3
VCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
GND
I/O15
I/O14
I/O13
I/O12
GND
I/O11
I/O10
I/O9
I/O8
NC
LCAS
UCAS
OE
A9
A8
A7
A6
A5
A4
GND
PIN DESCRIPTIONS
A0-A9
I/O0-15
WE
OE
RAS
UCAS
LCAS
Vcc
GND
NC
Address Inputs
Data Inputs/Outputs
Write Enable
Output Enable
Row Address Strobe
Upper Column Address Strobe
Lower Column Address Strobe
Power
Ground
No Connection
ISSI reserves the right to make changes to its products at any time without notice in order to improve design and supply the best possible product. We assume no responsibility for any
errors which may appear in this publication. © Copyright 2000, Integrated Silicon Solution, Inc.
Integrated Silicon Solution, Inc. — 1-800-379-4774
Rev. A
03/03/00
1
IS41C16105
IS41LV16105
Functional Description
The IS41C16105 and IS41LV16105 is a CMOS DRAM
optimized for high-speed bandwidth, low power applica-
tions. During READ or WRITE cycles, each bit is uniquely
addressed through the 16 address bits. These are entered
ten bits (A0-A9) at a time. The row address is latched by
the Row Address Strobe (RAS). The column address is
latched by the Column Address Strobe (CAS).
RAS
is
used to latch the first nine bits and
CAS
is used the latter
nine bits.
The IS41C16105 and IS41LV16105 has two
CAS
con-
trols,
LCAS
and
UCAS.
The
LCAS
and
UCAS
inputs
internally generates a
CAS
signal functioning in an iden-
tical manner to the single
CAS
input on the other 1M x 16
DRAMs. The key difference is that each
CAS
controls its
corresponding I/O tristate logic (in conjunction with
OE
and
WE
and
RAS). LCAS
controls I/O0 through I/O7 and
UCAS
controls I/O8 through I/O15.
The IS41C16105 and IS41LV16105
CAS
function is deter-
mined by the first
CAS
(LCAS or
UCAS)
transitioning
LOW and the last transitioning back HIGH. The two
CAS
controls give the IS41C16105 and IS41LV16105 both
BYTE READ and BYTE WRITE cycle capabilities.
ISSI
Write Cycle
®
A write cycle is initiated by the falling edge of
CAS
and
WE,
whichever occurs last. The input data must be valid
at or before the falling edge of
CAS
or
WE,
whichever
occurs last.
Refresh Cycle
To retain data, 1,024 refresh cycles are required in each
16 ms period. There are two ways to refresh the memory.
1. By clocking each of the 1,024 row addresses (A0
through A9) with
RAS
at least once every 16 ms. Any
read, write, read-modify-write or
RAS-only
cycle re-
freshes the addressed row.
2. Using a
CAS-before-RAS
refresh cycle.
CAS-before-
RAS
refresh is activated by the falling edge of
RAS,
while holding
CAS
LOW. In
CAS-before-RAS
refresh
cycle, an internal 9-bit counter provides the row ad-
dresses and the external address inputs are ignored.
CAS-before-RAS
is a refresh-only mode and no data
access or device selection is allowed. Thus, the output
remains in the High-Z state during the cycle.
Power-On
After application of the V
CC
supply, an initial pause of
200 µs is required followed by a minimum of eight
initialization cycles (any combination of cycles contain-
ing a
RAS
signal).
During power-on, it is recommended that
RAS
track with
V
CC
or be held at a valid V
IH
to avoid current surges.
Memory Cycle
A memory cycle is initiated by bring
RAS
LOW and it is
terminated by returning both
RAS
and
CAS
HIGH. To
ensures proper device operation and data integrity any
memory cycle, once initiated, must not be ended or
aborted before the minimum t
RAS
time has expired. A new
cycle must not be initiated until the minimum precharge
time t
RP
, t
CP
has elapsed.
Read Cycle
A read cycle is initiated by the falling edge of
CAS
or
OE,
whichever occurs last, while holding
WE
HIGH. The
column address must be held for a minimum time speci-
fied by t
AR
. Data Out becomes valid only when t
RAC
, t
AA
,
t
CAC
and t
OEA
are all satisfied. As a result, the access time
is dependent on the timing relationships between these
parameters.
4
Integrated Silicon Solution, Inc. — 1-800-379-4774
Rev. A
03/03/00
IS41C16105
IS41LV16105
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
T
V
CC
I
OUT
P
D
T
A
Parameters
Voltage on Any Pin Relative to GND
Supply Voltage
Output Current
Power Dissipation
Commercial Operation Temperature
Extended Temperature
Industrail Temperature
Storage Temperature
5V
3.3V
5V
3.3V
Rating
–1.0 to +7.0
–0.5 to +4.6
–1.0 to +7.0
–0.5 to +4.6
50
1
0 to +70
–30 to +85
–40 to +85
–55 to +125
Unit
V
V
mA
W
°C
°C
°C
°C
ISSI
®
T
STG
Note:
1. Stress greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent
damage to the device. This is a stress rating only and functional operation of the device at these
or any other conditions above those indicated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions for extended periods may affect
reliability.
RECOMMENDED OPERATING CONDITIONS
(Voltages are referenced to GND.)
Symbol
V
CC
V
IH
V
IL
T
A
Parameter
Supply Voltage
Input High Voltage
Input Low Voltage
Commercial Ambient Temperature
Extended Ambient Temperature
Industrail Ambient Temperature
5V
3.3V
5V
3.3V
5V
3.3V
Min.
4.5
3.0
2.4
2.0
–1.0
–0.3
0
–30
–40
Typ.
5.0
3.3
—
—
—
—
—
—
—
Max.
5.5
3.6
V
CC
+ 1.0
V
CC
+ 0.3
0.8
0.8
70
85
85
Unit
V
V
V
°C
°C
°C
CAPACITANCE
(1,2)
Symbol
C
IN
1
C
IN
2
C
IO
Parameter
Input Capacitance: A0-A9
Input Capacitance:
RAS, UCAS, LCAS, WE, OE
Data Input/Output Capacitance: I/O0-I/O15
Max.
5
7
7
Unit
pF
pF
pF
Notes:
1. Tested initially and after any design or process changes that may affect these parameters.
2. Test conditions: T
A
= 25°C, f = 1 MHz,
Integrated Silicon Solution, Inc. — 1-800-379-4774
Rev. A
03/03/00
5
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