www.docs.chipfind.ru
February 2005
Copyright Alliance Semiconductor. All rights reserved.
AS7C252MPFD18A
2/11/05, v.1.1
Alliance Semiconductor
1 of 18
2.5V 2M
18 pipelined burst synchronous SRAM
Features
Organization: 2,097,152 words 18 bits
Fast clock speeds to 200 MHz
Fast clock to data access:
3.1/3.5/3.8 ns
Fast OE access time: 3.1/3.5/3.8 ns
Fully synchronous register-to-register operation
Double-cycle deselect
Asynchronous output enable control
Available in 100-pin TQFP package
Individual byte write and global write
Multiple chip enables for easy expansion
2.5V core power supply
Linear or interleaved burst control
Snooze mode for reduced power-standby
Common data inputs and data outputs
Logic block diagram
Selection guide
-200
-166
-133
Units
Minimum cycle time
5
6
7.5
ns
Maximum clock frequency
200
166
133
MHz
Maximum pipelined clock access time
3.1
3.5
3.8
ns
Maximum operating current
450
400
350
mA
Maximum standby current
170
150
140
mA
Maximum CMOS standby current (DC)
90
90
90
mA
Burst logic
ADV
ADSC
ADSP
CLK
LBO
CLK
CLR
CS
21
19
21
A[20:0]
21
Address
D
Q
CS
CLK
register
2M x 18
Memory
array
18
18
DQb
CLK
D
Q
Byte Write
registers
DQa
CLK
D
Q
Byte Write
registers
Enable
CLK
D
Q
register
Enable
CLK
D
Q
delay
register
CE
Output
registers
Input
registers
Power
down
DQ[a,b]
2
CE0
CE1
CE2
BW
b
BW
a
OE
ZZ
OE
CLK
CLK
BWE
GWE
18
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AS7C252MPFD18A
2.5V 32 Mb Synchronous SRAM products list
1,2
1 Core Power Supply: VDD = 2.5V + 0.125V
2 I/O Supply Voltage: VDDQ = 2.5V + 0.125V
PL-SCD
:
Pipelined Burst Synchronous SRAM - Single Cycle Deselect
PL-DCD
:
Pipelined Burst Synchronous SRAM - Double Cycle Deselect
FT
:
Flow-through Burst Synchronous SRAM
NTD
1
-PL
:
Pipelined Burst Synchronous SRAM with NTD
TM
NTD-FT
:
Flow-through Burst Synchronous SRAM with NTD
TM
Org
Part Number
Mode
Speed
2MX18
AS7C252MPFS18A
PL-SCD
200/166/133 MHz
1MX32
AS7C251MPFS32A
PL-SCD
200/166/133 MHz
1MX36
AS7C251MPFS36A
PL-SCD
200/166/133 MHz
2MX18
AS7C252MPFD18A
PL-DCD
200/166/133 MHz
1MX32
AS7C251MPFD32A
PL-DCD
200/166/133 MHz
1MX36
AS7C251MPFD36A
PL-DCD
200/166/133 MHz
2MX18
AS7C252MFT18A
FT
7.5/8.5/10 ns
1MX32
AS7C251MFT32A
FT
7.5/8.5/10 ns
1MX36
AS7C251MFT36A
FT
7.5/8.5/10 ns
2MX18
AS7C252MNTD18A
NTD-PL
200/166/133 MHz
1MX32
AS7C251MNTD32A
NTD-PL
200/166/133 MHz
1MX36
AS7C251MNTD36A
NTD-PL
200/166/133 MHz
2MX18
AS7C252MNTF18A
NTD-FT
7.5/8.5/10 ns
1MX32
AS7C251MNTF32A
NTD-FT
7.5/8.5/10 ns
1MX36
AS7C251MNTF36A
NTD-FT
7.5/8.5/10 ns
1NTD: No Turnaround Delay. NTD
TM
is a trademark of Alliance Semiconductor Corporation. All trademarks mentioned in this document are the property of
their respective owners.
2/11/05, v.1.1
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AS7C252MPFD18A
Pin assignment
100-pin TQFP - top view
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
LBO
A
A
A
A
A1
A0
NC
A
V
SS
V
DD
A
A
A
A
A
A
A
A
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
A A
CE
0
CE
1
NC
NC
BW
b
BW
a
CE
2
V
DD
V
SS
CLK
GW
E
BW
E
OE
AD
SC
AD
SP
AD
V
A
A
TQFP 14 x 20mm
A
NC
NC
NC
V
DDQ
V
SSQ
NC
NC
DQb0
DQb1
V
SSQ
V
DDQ
DQb2
DQb3
NC
V
DD
NC
V
SS
DQb4
DQb5
V
DDQ
V
SSQ
DQb6
DQb7
DQPb
NC
V
SSQ
V
DDQ
NC
NC
NC
A
NC
NC
V
DDQ
V
SSQ
NC
DQPa
DQa7
DQa6
V
SSQ
V
DDQ
DQa5
DQa4
V
SS
ZZ
DQa3
DQa2
V
DDQ
V
SSQ
DQa1
DQa0
NC
NC
V
SSQ
V
DDQ
NC
NC
NC
V
DD
NC
AS7C252MPFD18A
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Alliance Semiconductor
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Functional description
The AS7C252MPFD18A is a high-performance CMOS 32-Mbit synchronous Static Random Access Memory (SRAM) device
organized as 2,097,152 words 18 bits. It incorporates a two-stage register-register pipeline for highest frequency on any given
technology.
Fast cycle times of 5/6/7.5 ns with clock access times (t
CD
) of 3.1/3.5/3.8 ns enable 200,167 and 133MHz 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 mode is selectable with the
LBO
input.
With
LBO
unconnected or driven high, burst operations use an interleaved count sequence. With
LBO
driven low, the device
uses a linear count sequence.
Write cycles are performed by disabling the output buffers with OE and asserting a write command. A global write enable
GWE writes all 18 bits regardless of the state of individual BW[a,b] inputs. Alternately, when GWE is high, one or more bytes
may be written by asserting BWE and the appropriate individual byte BWn signals.
BWn is ignored on the clock edge that samples ADSP low, but it 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. This device operates in double-
cycle deselect feature during read cycles.
Read or write cycles may also be initiated with ADSC instead of ADSP. The differences between cycles initiated with ADSC
and ADSP are as follows:
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.
The AS7C252MPFD18A operates with a 2.5V
5% power supply for the device core (V
DD
)
. These devices are available in a 100-
pin TQFP package.
TQFP capacitance
* Guaranteed not tested
TQFP thermal resistance
Parameter
Symbol
Test conditions
Min
Max
Unit
Input capacitance
C
IN
*
V
IN
= 0V
-
5
pF
I/O capacitance
C
I/O
*
V
OUT
= 0V
-
7
pF
Description
Conditions
Symbol
Typical
Units
Thermal resistance
(junction to ambient)
1
1 This parameter is sampled
Test conditions follow standard test methods
and procedures for measuring thermal
impedance, per EIA/JESD51
1layer
JA
40
C/W
4layer
JA
22
C/W
Thermal resistance
(junction to top of case)
1
JC
8
C/W
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AS7C252MPFD18A
Signal descriptions
Snooze Mode
SNOOZE MODE is a low current, power-down mode in which the device is deselected and current is reduced to I
SB2
. The duration of
SNOOZE MODE is dictated by the length of time the ZZ is in a High state.
The ZZ pin is an asynchronous, active high input that causes the device to enter SNOOZE MODE.
When the ZZ pin becomes a logic High, I
SB2
is guaranteed after the time t
ZZI
is met. After entering SNOOZE MODE, all inputs except ZZ is
disabled and all outputs go to High-Z. Any operation pending when entering SNOOZE MODE is not guaranteed to successfully complete.
Therefore, SNOOZE MODE (READ or WRITE) must not be initiated until valid pending operations are completed. Similarly, when exiting
SNOOZE MODE during t
PUS
, only a DESELECT or READ cycle should be given while the SRAM is transitioning out of SNOOZE MODE.
Pin
I/O
Properties
Description
CLK
I
CLOCK
Clock. All inputs except OE, ZZ, and LBO are synchronous to this clock.
A,A0,A1
I
SYNC
Address. Sampled when all chip enables are active and when ADSC or ADSP are asserted.
DQ[a,b]
I/O
SYNC
Data. Driven as output when the chip is enabled and when OE is active.
CE0
I
SYNC
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.
CE1, CE2
I
SYNC
Synchronous chip enables, active high, and active low, respectively. Sampled on clock edges when
ADSC is active or when CE0 and ADSP are active.
ADSP
I
SYNC
Address strobe processor. Asserted low to load a new address or to enter standby mode.
ADSC
I
SYNC
Address strobe controller. Asserted low to load a new address or to enter standby mode.
ADV
I
SYNC
Advance. Asserted low to continue burst read/write.
GWE
I
SYNC
Global write enable. Asserted low to write all 18 bits. When high, BWE and BW[a,b] control write
enable.
BWE
I
SYNC
Byte write enable. Asserted low with GWE high to enable effect of BW[a:d] inputs.
BW[a,b]
I
SYNC
Write enables. Used to control write of individual bytes when GWE is high and BWE is low. If any of
BW[a,b] is active with GWE high and BWE low, the cycle is a write cycle. If all BW[a,b] are inactive,
the cycle is a read cycle.
OE
I
ASYNC
Asynchronous output enable. I/O pins are driven when OE is active and chip is in read mode.
LBO
I
STATIC
Selects Burst mode. When tied to V
DD
or left floating, device follows interleaved Burst order. When
driven Low, device follows linear Burst order. This signal is internally pulled High.
ZZ
I
ASYNC
Snooze. Places device in low power mode; data is retained. Connect to GND if unused.
NC
-
-
No connect
AS7C252MPFD18A
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v.1.1
Alliance Semiconductor
6 of 18
Write enable truth table (per byte)
Key: X = don't care, L = low, H = high, n = a, b;
BWE
,
BWn
= internal write signal.
Asynchronous Truth Table
Notes:
1. X means "Don't Care"
2. ZZ pin is pulled down internally
3. For write cycles that follows read cycles, the output buffers must be disabled with OE, otherwise data bus contention will occur.
4. Snooze mode means power down state of which stand-by current does not depend on cycle times
5. Deselected means power down state of which stand-by current depends on cycle times
Burst sequence table
Function
GWE
BWE
BWa
BWb
Write All Bytes
L
X
X
X
H
L
L
L
Write Byte a
H
L
L
H
Write Byte b
H
L
H
L
Read
H
H
X
X
H
L
H
H
Operation
ZZ
OE
I/O Status
Snooze mode
H
X
High-Z
Read
L
L
Dout
L
H
High-Z
Write L
X
Din,
High-Z
Deselected
L
X
High-Z
Interleaved burst address (LBO = 1)
Linear burst address (LBO = 0)
A1 A0
A1 A0
A1 A0
A1 A0
A1 A0
A1 A0
A1 A0
A1 A0
Starting Address
0 0
0 1
1 0
1 1
Starting Address
0 0
0 1
1 0
1 1
First Increment
0 1
0 0
1 1
1 0
First Increment
0 1
1 0
1 1
0 0
Second Increment
1 0
1 1
0 0
0 1
Second Increment
1 0
1 1
0 0
0 1
Third Increment
1 1
1 0
0 1
0 0
Third Increment
1 1
1 0
0 1
1 0
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AS7C252MPFD18A
Synchronous truth table
[4]
CE0
1
1 X = don't care, L = low, H = high
CE1
CE2
ADSP ADSC ADV
WRITE
[2]
2 For WRITE, L means any one or more byte write enable signals (BWa or BWb) and BWE are LOW or GWE is LOW. WRITE = HIGH for all BWx, BWE,
GWE HIGH. See "Write enable truth table (per byte)," on page 6 for more information.
OE
Address accessed
CLK
Operation
DQ
H
X
X
X
L
X
X
X
NA
L to H
Deselect
Hi
-Z
L
L
X
L
X
X
X
X
NA
L to H
Deselect
Hi
-Z
L
L
X
H
L
X
X
X
NA
L to H
Deselect
Hi
-Z
L
X
H
L
X
X
X
X
NA
L to H
Deselect
Hi
-Z
L
X
H
H
L
X
X
X
NA
L to H
Deselect
Hi
-Z
L
H
L
L
X
X
X
L
External
L to H
Begin read
Q
L
H
L
L
X
X
X
H
External
L to H
Begin read
Hi
-Z
L
H
L
H
L
X
H
L
External
L to H
Begin read
Q
L
H
L
H
L
X
H
H
External
L to H
Begin read
Hi
-Z
X
X
X
H
H
L
H
L
Next
L to H
Continue read
Q
X
X
X
H
H
L
H
H
Next
L to H
Continue read
Hi
-Z
X
X
X
H
H
H
H
L
Current
L to H
Suspend read
Q
X
X
X
H
H
H
H
H
Current
L to H
Suspend read
Hi
-Z
H
X
X
X
H
L
H
L
Next
L to H
Continue read
Q
H
X
X
X
H
L
H
H
Next
L to H
Continue read
Hi
-Z
H
X
X
X
H
H
H
L
Current
L to H
Suspend read
Q
H
X
X
X
H
H
H
H
Current
L to H
Suspend read
Hi
-Z
L
H
L
H
L
X
L
X
External
L to H
Begin write
D
3
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
4 ZZ pin is always Low.
X
X
X
H
H
L
L
X
Next
L to H
Continue write
D
H
X
X
X
H
L
L
X
Next
L to H
Continue write
D
X
X
X
H
H
H
L
X
Current
L to H
Suspend write
D
H
X
X
X
H
H
L
X
Current
L to H
Suspend write
D
AS7C252MPFD18A
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8 of 18
Absolute maximum ratings
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.
Recommended operating conditions
DC electrical characteristics
LBO and ZZ pins have an internal pull-up or pull-down, and input leakage = 10
A.
*
V
IH
max < VDD +1.5V for pulse width less than 0.2 X t
CYC
**
V
IL
min = -1.5 for pulse width less than 0.2 X t
CYC
I
DD
operating conditions and maximum limits
Parameter
Symbol
Min
Max
Unit
Power supply voltage relative to GND
V
DD
, V
DDQ
0.3
+3.6
V
Input voltage relative to GND (input pins)
V
IN
0.3
V
DD
+ 0.3
V
Input voltage relative to GND (I/O pins)
V
IN
0.3
V
DDQ
+ 0.3
V
Power dissipation
P
d
1.8
W
Short circuit output current
I
OUT
20 mA
Storage temperature
T
stg
65
+150
o
C
Temperature under bias
T
bias
65 +135
o
C
Parameter
Symbol
Min
Nominal
Max
Unit
Supply voltage for inputs
V
DD
2.375
2.5
2.625
V
Supply voltage for I/O
V
DDQ
2.375
2.5
2.625
V
Ground supply
Vss
0
0
0
V
Parameter
Sym
Conditions
Min
Max
Unit
Input leakage current
|I
LI
|
V
DD
= Max, OV < V
IN
< V
DD
-2
2
A
Output leakage current
|I
LO
|
OE
V
IH
, V
DD
= Max, OV < V
OUT
< V
DDQ
-2
2
A
Input high (logic 1) voltage
V
IH
Address and control pins
1.7
*
V
DD
+0.3
V
I/O pins
1.7
*
V
DDQ
+0.3
V
Input low (logic 0) voltage
V
IL
Address and control pins
-0.3
**
0.7
V
I/O pins
-0.3
**
0.7
V
Output high voltage
V
OH
I
OH
= 4 mA, V
DDQ
= 2.375V
1.7
V
Output low voltage
V
OL
I
OL
= 8 mA, V
DDQ
= 2.625V
0.7
V
Parameter
Sym
Conditions
-200
-166
-133
Unit
Operating power supply current
1
1 I
CC
given with no output loading. I
CC
increases with faster cycle times and greater output loading.
I
CC
CE0 < V
IL
, CE1 > V
IH
, CE2 < V
IL
, f = f
Max
,
I
OUT
= 0 mA, ZZ
< V
IL
450
400
350
mA
Standby power supply current
I
SB
All V
IN
0.2V or > V
DD
0.2V, Deselected,
f = f
Max
, ZZ
< V
IL
170
150
140
mA
I
SB1
Deselected, f = 0, ZZ
< 0.2V,
all V
IN
0.2V or V
DD
0.2V
90
90
90
I
SB2
Deselected, f = f
Max
, ZZ
V
DD
0.2V,
all V
IN
V
IL
or
V
IH
80
80
80
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AS7C252MPFD18A
Timing characteristics over operating range
Snooze Mode Electrical Characteristics
Parameter
Sym
200
166
-133
Unit
Notes
1
1 See "Notes" on page 15.
Min
Max
Min
Max
Min
Max
Clock frequency
f
Max
200
166
133
MHz
Cycle time
t
CYC
5
6
7.5
ns
Clock access time
t
CD
3.1
3.5
3.8
ns
Output enable low to data valid
t
OE
3.1
3.5
3.8
ns
Clock high to output low Z
t
LZC
0
0
0
ns
2,3,4
Data output invalid from clock high
t
OH
1.5
1.5
1.5
ns
2
Output enable low to output low Z
t
LZOE
0
0
0
ns
2,3,4
Output enable high to output high Z
t
HZOE
3.0
3.4
3.8
ns
2,3,4
Clock high to output high Z
t
HZC
3.0
3.4
3.8
ns
2,3,4
Output enable high to invalid output
t
OHOE
0
0
0
ns
Clock high pulse width
t
CH
2.0
2.4
2.4
ns
5
Clock low pulse width
t
CL
2.0
2.4
2.4
ns
5
Address setup to clock high
t
AS
1.4
1.5
1.5
ns
6
Data setup to clock high
t
DS
1.4
1.5
1.5
ns
6
Write setup to clock high
t
WS
1.4
1.5
1.5
ns
6,7
Chip select setup to clock high
t
CSS
1.4
1.5
1.5
ns
6,8
Address hold from clock high
t
AH
0.4
0.5
0.5
ns
6
Data hold from clock high
t
DH
0.4
0.5
0.5
ns
6
Write hold from clock high
t
WH
0.4
0.5
0.5
ns
6,7
Chip select hold from clock high
t
CSH
0.4
0.5
0.5
ns
6,8
ADV setup to clock high
t
ADVS
1.4
1.5
1.5
ns
6
ADSP setup to clock high
t
ADSPS
1.4
1.5
1.5
ns
6
ADSC setup to clock high
t
ADSCS
1.4
1.5
1.5
ns
6
ADV hold from clock high
t
ADVH
0.4
0.5
0.5
ns
6
ADSP hold from clock high
t
ADSPH
0.4
0.5
0.5
ns
6
ADSC hold from clock high
t
ADSCH
0.4
0.5
0.5
ns
6
Description
Conditions
Symbol
Min
Max
Units
Current during Snooze Mode
ZZ > V
IH
I
SB2
80
mA
ZZ active to input ignored
t
PDS
2
cycle
ZZ inactive to input sampled
t
PUS
2
cycle
ZZ active to SNOOZE current
t
ZZI
2
cycle
ZZ inactive to exit SNOOZE current
t
RZZI
0
cycle
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v.1.1
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10 of 18
Key to switching waveforms
Timing waveform of read cycle
Note: = XOR when LBO = high/no connect; = ADD when LBO = low. BW[a:d] is don't care.
*Outputs are disabled within two clk cycles after DSEL command
don't care
Falling input
Rising input
Undefined
CE1
t
CYC
t
CH
t
CL
t
ADSPS
t
ADSPH
t
AS
t
AH
t
WS
t
ADVS
t
OH
CLK
ADSP
ADSC
Address
GWE, BWE
CE0, CE2
ADV
OE
Dout
t
CSS
t
HZC
t
CD
t
WH
t
ADVH
t
HZOE
t
ADSCS
t
ADSCH
LOAD NEW ADDRESS
ADV inserts wait states
Q(A210)
Q(A211)
Q(A3)
Q(A2)
Q(A201)
Q(A301)
Q(A310)
Q(A1)
A2
A1
A3
t
OE
t
LZOE
t
CSH
Read
Q(A1)
Suspend
Read
Q(A1)
Read
Q(A2)
Burst
Read
Q(A 201)
Read
Q(A3)
DSEL*
Burst
Read
Q(A 210)
Suspend
Read
Q(A 210)
Burst
Read
Q(A 211)
Burst
Read
Q(A 301)
Burst
Read
Q(A 310)
Burst
Read
Q(A 311)
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AS7C252MPFD18A
Timing waveform of write cycle
Note: = XOR when LBO = high/no connect; = ADD when LBO = low.
t
CYC
t
CL
t
ADSPS
t
ADSPH
t
ADSCS
t
ADSCH
t
AS
t
AH
t
WS
t
WH
t
CSS
t
ADVS
t
DS
t
DH
CLK
ADSP
ADSC
Address
BWE
CE0, CE2
ADV
OE
Din
t
CSH
t
ADVH
D(A201)
D(A210)
D(A3)
D(A2)
D(A201)
D(A301)
D(A310)
D(A1)
D(A211)
ADV SUSPENDS BURST
ADSC LOADS NEW ADDRESS
A1
A2
A3
t
CH
CE1
BW[a:d]
Read
Q(A1)
Sus-
pend
Write
D(A1)
Read
Q(A2)
Suspend
Write
D(A 2)
ADV
Burst
Write
D(A 201)
Suspend
Write
D(A 201)
ADV
Burst
Write
D(A 210)
Write
D(A 3)
Burst
Write
D(A 301)
ADV
Burst
Write
D(A 211)
ADV
Burst
Write
D(A 310)
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v.1.1
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12 of 18
Timing waveform of read/write cycle (ADSP Controlled; ADSC High)
Note: = XOR when LBO = high/no connect; = ADD when LBO = low.
t
CH
t
CYC
t
CL
t
ADSPS
t
ADSPH
t
AS
t
AH
t
WS
t
WH
t
ADVS
t
DS
t
DH
t
OH
CLK
ADSP
Address
GWE
CE0, CE2
ADV
OE
Din
Dout
t
CD
t
ADVH
t
LZOE
t
OE
t
LZC
Q(A1)
Q(A301)
D(A2)
Q(A3)
Q(A310)
Q(A311)
A1
A2
A3
CE1
t
HZOE
DSEL
Suspend
Read
Q(A1)
Read
Q(A1)
Suspend
Write
D(A 2)
ADV
Burst
Read
Q(A 301)
ADV
Burst
Read
Q(A 310)
ADV
Burst
Read
Q(A 311)
Read
Q(A2)
Read
Q(A3)
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AS7C252MPFD18A
Timing waveform of read/write cycle(ADSC controlled, ADSP = HIGH)
t
CYC
t
CH
t
CL
t
ADSCH
CLK
ADSC
ADDRESS
A2
A1
t
ADSCS
A3
A4
A6
A5
A7
A8
A9
t
AH
t
AS
GWE
t
WH
t
WS
t
CSH
CE0,CE2
t
CSS
ADV
t
LZOE
t
OE
t
HZOE
Q(A1)
Q(A2)
Q(A3)
Q(A4)
Q(A8)
Q(A9)
t
LZOE
t
OH
D(A6)
D(A7)
D(A5)
t
DS
t
DH
OE
Dout
Din
READ
Q(A1)
READ
Q(A2)
READ
Q(A3)
READ
Q(A4)
WRITE
D(A5)
WRITE
D(A6)
WRITE
D(A7)
READ
Q(A8)
READ
Q(A9)
CE1
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AS7C252MPFD18A
Timing waveform of power down cycle
t
CYC
t
CH
t
CL
t
ADSPS
CLK
ADSP
ADDRESS
A1
t
ADSPS
A2
GWE
t
WH
t
WS
t
CSH
CE0,CE2
t
CSS
ADV
t
LZOE
t
OE
t
HZOE
Q(A1)
D(A2(01))
D(A2)
OE
Dout
Din
ADSC
t
HZC
t
PDS
ZZ Setup Cycle
t
PUS
ZZ Recovery Cycle
Normal Operation Mode
CE1
ZZ
READ
Q(A1)
S
USPEND
READ
Q(A1)
C
ON
-
TINUE
WRITE
D(A2
01)
S
USPEND
WRITE
D(A2)
READ
Q(A2)
Sleep
I
SB2
State
t
ZZI
t
RZZI
I
supply
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AS7C252MPFD18A
AC test conditions
Notes
1
For test conditions, see "AC test conditions", Figures A, B, and C.
2
This parameter is measured with output load condition in Figure C.
3
This parameter is sampled but not 100% tested.
4
t
HZOE
is less than t
LZOE
, and t
HZC
is less than t
LZC
at any given temperature and voltage.
5
t
CH
is measured as high if above VIH, and t
CL
is measured as low if below VIL.
6
This is a synchronous device. All addresses must meet the specified setup and hold times for all rising edges of CLK. All other synchronous inputs must
meet the setup and hold times for all rising edges of CLK when chip is enabled.
7
Write refers to
GWE, BWE, and BW[a,b].
8
Chip select refers to
CE0, CE1, and CE2.
Z
0
= 50
D
OUT
50
Figure B: Output load (A)
30 pF*
Figure A: Input waveform
10%
90%
GND
90%
10%
+2.5V
Output load: For t
LZC
, t
LZOE
, t
HZOE
, t
HZC
, see Figure C. For all others, see Figure B.
Input pulse level: GND to 2.5V. See Figure A.
Input rise and fall time (measured at 0.25V and 2.25V): 2 ns. See Figure A.
Input and output timing reference levels: 1.25V.
V
L
= V
DDQ
/2
Thevenin equivalent:
353
/1538
5 pF*
319
/1667
D
OUT
GND
Figure C: Output load(B)
*including scope
and jig capacitance
+2.5V
AS7C252MPFD18A
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v.1.1
Alliance Semiconductor
16 of 18
Package dimensions
100-pin quad flat pack (TQFP)
TQFP
Min
Max
A1
0.05
0.15
A2
1.35
1.45
b
0.22
0.38
c
0.09
0.20
D
13.90
14.10
E
19.90
20.10
e
0.65 nominal
Hd
15.85
16.15
He
21.80
22.20
L
0.45
0.75
L1
1.00 nominal
0
7
Dimensions in millimeters
A1 A2
L1
L
c
He E
Hd
D
b
e
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AS7C252MPFD18A
Ordering information
Note:
Add suffix `N' to the above part numbers for lead free parts (Ex AS7C252MPFD18A-200TQC
N)
Part numbering guide
1. Alliance Semiconductor SRAM prefix
2. Operating voltage: 25 = 2.5V
3. Organization: 2M = 2Meg
4. Pipelined mode
5. Deselect: D = Double cycle deselect
6. Organization: 18 = x 18
7. Production version: A = first production version
8. Clock speed (MHz)
9. Package type: TQ = TQFP
10. Operating temperature: C = commercial (0
C to 70 C); I = industrial (-40 C to 85 C)
11. N = Lead Free Part
Package & Width
-200
-166
-133
TQFP x 18
AS7C252MPFD18A-200TQC
AS7C252MPFD18A-166TQC
AS7C252MPFD18A-133TQC
AS7C252MPFD18A-200TQI
AS7C252MPFD18A-166TQI
AS7C252MPFD18A-133TQI
AS7C
25
2M
PF
D
18
A
XXX
TQ
C/I
X
1
2
3
4
5
6
7
8
9
10
11
Alliance Semiconductor Corporation
2575, Augustine Drive,
Santa Clara, CA 95054
Tel: 408 - 855 - 4900
Fax: 408 - 855 - 4999
www.alsc.com
Copyright Alliance Semiconductor
All Rights Reserved
Part Number: AS7C252MPFD18A
Document Version: v.1.1
Copyright 2003 Alliance Semiconductor Corporation. All rights reserved. Our three-point logo, our name and Intelliwatt are trademarks or registered trademarks of Alli-
ance. All other brand and product names may be the trademarks of their respective companies. Alliance reserves the right to make changes to this document and its products
at any time without notice. Alliance assumes no responsibility for any errors that may appear in this document. The data contained herein represents Alliance's best data and/
or estimates at the time of issuance. Alliance reserves the right to change or correct this data at any time, without notice. If the product described herein is under develop-
ment, significant changes to these specifications are possible. The information in this product data sheet is intended to be general descriptive information for potential cus-
tomers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or customer. Alliance does not assume any responsibility or liability
arising out of the application or use of any product described herein, and disclaims any express or implied warranties related to the sale and/or use of Alliance products
including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual property rights, except as express agreed to in
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