The AS7C3364PFS32A and AS7C3364PFS36A are high-performance CMOS 2-Mbit synchronous Static Random Access Memory (SRAM)
devices organized as 65,536 words × 32 or 36 bits, and incorporate a two-stage register-register pipeline for highest frequency on any given
technology.
Timing for these devices is compatible with existing Pentium
®
synchronous cache specifications. This architecture is suited for ASIC, DSP
(TMS320C6X), and PowerPC
™
*
-based systems in computing, datacomm, instrumentation, and telecommunications systems.
Fast cycle times of 6/6.7/7.5/10 ns with clock access times (t
CD
) of 3.5/3.8/4.0/5.0 ns enable 166, 150, 133 and 100 MHz bus frequencies.
Three chip enable (CE) inputs permit easy memory expansion. Burst operation is initiated in one of two ways: the controller address strobe
(ADSC), or the processor address strobe (ADSP). The burst advance pin (ADV) allows subsequent internally generated burst addresses.
Read cycles are initiated with ADSP (regardless of WE and ADSC) using the new external address clocked into the on-chip address register
when ADSP is sampled Low, the chip enables are sampled active, and the output buffer is enabled with OE. In a read operation the data accessed
by the current address, registered in the address registers by the positive edge of CLK, are carried to the data-out registers and driven on the
output pins on the next positive edge of CLK. ADV is ignored on the clock edge that samples ADSP asserted, but is sampled on all subsequent
clock edges. Address is incremented internally for the next access of the burst when ADV is sampled Low, and both address strobes are High.
Burst operation is selectable with the LBO input. With LBO unconnected or driven High, burst operations use a Pentium
®
count sequence. With
LBO driven LOW the device uses a linear count sequence suitable for PowerPC
™
and many other applications.
,
Write cycles are performed by disabling the output buffers with OE and asserting a write command. A global write enable GWE writes all 32/
36 bits regardless of the state of individual BW[a:d] inputs. Alternately, when GWE is High, one or more bytes may be written by asserting
BWE and the appropriate individual byte BWn signal(s).
BWn is ignored on the clock edge that samples ADSP Low, but is sampled on all subsequent clock edges. Output buffers are disabled when BWn
is sampled LOW (regardless of OE). Data is clocked into the data input register when BWn is sampled Low. Address is incremented internally to
the next burst address if BWn and ADV are sampled Low.
Read or write cycles may also be initiated with ADSC instead of ADSP. The differences between cycles initiated with ADSC and ADSP follow.
• ADSP must be sampled HIGH when ADSC is sampled LOW to initiate a cycle with ADSC.
• WE signals are sampled on the clock edge that samples ADSC LOW (and ADSP High).
• Master chip enable CE0 blocks ADSP, but not ADSC.
ASAS7C3364PFS32A and ASAS7C3364PFS36A family operates from a core 3.3V power supply. I/Os use a separate power supply that can
operate at 2.5V or 3.3V. These devices are available in a 100-pin 14 × 20 mm TQFP package.
*PowerPC
™
is a tradenark International Business Machines Corporation.
Capacitance
Parameter
Input capacitance
I/O capacitance
Symbol
C
IN
C
I/O
Signals
Address and control pins
I/O pins
Test conditions
V
IN
= 0V
V
IN
= V
OUT
= 0V
Max
5
7
Unit
pF
pF
Write enable truth table (per byte)
GWE
L
H
H
H
Key:
BWE
X
L
H
L
BWn
X
L
X
H
WEn
T
T
F*
F
*
X = Don’t Care, L = Low, H = High, T = True, F = False; *= Valid read; n = a, b, c, d;
WE
,
WEn
= internal write signal.
2/1/01
Alliance Semiconductor
P. 2 of 11
AS7C3364PFS32A
AS7C3364PFS36A
®
Signal descriptions
I/
Signal
O
CLK
I
A0–A15
I
DQ[a,b,c,d] I/O
CE0
CE1, CE2
ADSP
ADSC
ADV
GWE
BWE
I
I
I
I
I
I
I
Properties
CLOCK
SYNC
SYNC
SYNC
SYNC
SYNC
SYNC
SYNC
SYNC
SYNC
SYNC
ASYNC
STATIC
default =
HIGH
STATIC
ASYNC
Description
Clock. All inputs except OE, FT, ZZ, LBO are synchronous to this clock.
Address. Sampled when all chip enables are active and ADSC or ADSP are asserted.
Data. Driven as output when the chip is enabled and OE is active.
Master chip enable. Sampled on clock edges when ADSP or ADSC is active. When CE0 is
inactive, ADSP is blocked. Refer to the Synchronous Truth Table for more information.
Synchronous chip enables. Active HIGH and active Low, respectively. Sampled on clock
edges when ADSC is active or when CE0 and ADSP are active.
Address strobe processor. Asserted LOW to load a new bus address or to enter standby
mode.
Address strobe controller. Asserted LOW to load a new address or to enter standby mode.
Advance. Asserted LOW to continue burst read/write.
Global write enable. Asserted LOW to write all 32/36 bits. When High, BWE and BW[a:d]
control write enable.
Byte write enable. Asserted LOW with GWE = HIGH to enable effect of BW[a:d] inputs.
Write enables. Used to control write of individual bytes when GWE = HIGH and BWE =
Low. If any of BW[a:d] is active with GWE = HIGH and BWE = LOW the cycle is a write
cycle. If all BW[a:d] are inactive the cycle is a read cycle.
Asynchronous output enable. I/O pins are driven when OE is active and the chip is in read
mode.
Count mode. When driven High, count sequence follows Intel XOR convention. When
driven Low, count sequence follows linear convention.
This signal is internally pulled High.
18
Flow-through mode.When low, enables single register flow-through mode. Connect to V
DD
if unused or for pipelined operation.
Sleep. Places device in low power mode; data is retained. Connect to GND if unused.
BW[a,b,c,d] I
OE
LBO
FT
ZZ
I
I
I
I
Absolute maximum ratings
Parameter
Power supply voltage relative to GND
Input voltage relative to GND (input pins)
Input voltage relative to GND (I/O pins)
Power dissipation
DC output current
Storage temperature (plastic)
Temperature under bias
Symbol
V
DD
, V
DDQ
V
IN
V
IN
P
D
I
OUT
T
stg
T
bias
Min
–0.5
–0.5
–0.5
–
–
–65
–65
Max
+4.6
V
DD
+ 0.5
V
DDQ
+ 0.5
1.8
50
+150
+135
Unit
V
V
V
W
mA
o
C
o
C
Stresses 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 outside those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum
rating conditions may affect reliability.
2/1/01
Alliance Semiconductor
P. 3 of 11
AS7C3364PFS32A
AS7C3364PFS36A
®
Synchronous truth table
CE0
H
L
L
L
L
L
L
L
L
X
X
X
X
H
H
H
H
L
X
H
X
H
CE1
X
L
L
X
X
H
H
H
H
X
X
X
X
X
X
X
X
H
X
X
X
X
CE2
X
X
X
H
H
L
L
L
L
X
X
X
X
X
X
X
X
L
X
X
X
X
ADSP
X
L
H
L
H
L
L
H
H
H
H
H
H
X
X
X
X
H
H
X
H
X
ADSC
L
X
L
X
L
X
X
L
L
H
H
H
H
H
H
H
H
L
H
H
H
H
ADV
X
X
X
X
X
X
X
X
X
L
L
H
H
L
L
H
H
X
L
L
H
H
WEn
1
OE
X
X
X
X
X
L
H
L
H
L
H
L
H
L
H
L
H
X
X
X
X
X
Address accessed
NA
NA
NA
NA
NA
External
External
External
External
Next
Next
Current
Current
Next
Next
Current
Current
External
Next
Next
Current
Current
CLK
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
L to H
Operation
Deselect
Deselect
Deselect
Deselect
Deselect
Begin read
Begin read
Begin read
Begin read
Cont. read
Cont. read
Suspend read
Suspend read
Cont. read
Cont. read
Suspend read
Suspend read
Begin write
Cont. write
Cont. write
Suspend write
Suspend write
DQ
Hi−Z
Hi−Z
Hi−Z
Hi−Z
Hi−Z
Hi−Z
2
Hi−Z
Hi−Z
2
Hi−Z
Q
Hi−Z
Q
Hi−Z
Q
Hi−Z
Q
Hi−Z
D
3
D
D
D
D
X
X
X
X
X
X
X
F
F
F
F
F
F
F
F
F
F
T
T
T
T
T
Key: X = Don’t Care, L = Low, H = High.
1
See “Write enable truth table”on page 2 for more information.
2 Q in flow through mode.
3
For write operation following a READ,
OE
must be HIGH before the input data set up time and held HIGH throughout the input hold time.
Recommended operating conditions
Parameter
Supply voltage
3.3V I/O supply
voltage
2.5V I/O supply
voltage
Address and
control pins
I/O pins
Ambient operating temperature
Symbol
V
DD
V
SS
V
DDQ
V
SSQ
V
DDQ
V
SSQ
V
IH
V
IL
V
IH
V
IL
T
A
Min
3.135
0.0
3.135
0.0
2.35
0.0
2.0
–0.5
*
2.0
–0.5
*
0
Nominal
3.3
0.0
3.3
0.0
2.5
0.0
–
–
–
–
–
Max
3.6
0.0
3.6
0.0
2.9
0.0
V
DD
+ 0.3
0.8
V
DDQ
+ 0.3
0.8
70
Unit
V
V
V
V
V
°C
Input voltages
†
* V
IL
min = –2.0V for pulse width less than 0.2 × t
RC
.
† Input voltage ranges apply to 3.3V I/O operation. For 2.5V I/O operation, contact factory for input specifications.
2/1/01
Alliance Semiconductor
P. 4 of 11
AS7C3364PFS32A
AS7C3364PFS36A
®
TQFP thermal resistance
Description
Thermal resistance
(junction to ambient)
*
Thermal resistance
(junction to top of case)
*
* This parameter is sampled.
Conditions
Test conditions follow standard test methods and
procedures for measuring thermal impedance, per EIA/
JESD51
Symbol
θ
JA
θ
JC
Typical
46
2.8
Units
°C/W
°C/W
DC electrical characteristics
–166
Parameter
Input leakage
current
*
Output leakage
current
Operating power
supply current
Symbol
|I
LI
|
|I
LO
|
I
CC
I
SB
Standby power
supply current
I
SB1
I
SB2
Output voltage
V
OL
V
OH
Test conditions
V
DD
= Max, V
IN
= GND to V
DD
OE
≥
V
IH
, V
DD
= Max,
V
OUT
= GND to V
DD
CE0 = V
IL
, CE1 = V
IH
, CE2 = V
IL
,
f = f
Max
, I
OUT
= 0 mA
Deselected, f = f
Max
, ZZ
≤
V
IL
Deselected, f = 0, ZZ
≤
0.2V
all V
IN
≤
0.2V or
≥
V
DD
– 0.2V
Deselected, f = f
Max
, ZZ
≥
V
DD
– 0.2V
All V
IN
≤
V
IL
or
≥
V
IH
I
OL
= 8 mA, V
DDQ
= 3.465V
I
OH
= –4 mA, V
DDQ
= 3.135V
–150
–133
–100
Min Max Min Max Min Max Min Max Unit
–
–
–
–
–
–
–
2.4
2
2
475
130
30
30
0.4
–
–
–
–
–
–
–
–
2.4
2
2
450
110
30
30
0.4
–
–
–
–
–
–
–
–
2.4
2
2
425
100
30
30
0.4
–
–
–
–
–
–
–
–
2.4
2
2
325
90
30
30
0.4
–
V
mA
µA
µA
mA
* LBO pin has an internal pull-up and input leakage = ±10
µa.
Note: ICC given with no output loading. ICC increases with faster cycles times and greater output loading.
DC electrical characteristics for 2.5V I/O operation
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