November 2004
®
AS7C331MPFS32A
AS7C331MPFS36A
3.3V 1M
×
32/36 pipelined burst synchronous SRAM
Features
•
•
•
•
•
•
•
•
•
•
Organization: 1,048,576 words × 32 or 36 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
Single-cycle deselect
Asynchronous output enable control
Available in 100-pin TQFP and 165-ball BGA packages
Individual byte write and global write
Multiple chip enables for easy expansion
•
•
•
•
•
•
3.3V core power supply
2.5V or 3.3V I/O operation with separate V
DDQ
Linear or interleaved burst control
Snooze mode for reduced power-standby
Common data inputs and data outputs
Boundary Scan using IEEE 1149.1 JTAG function is avail-
able in 165 Ball BGA Package only.
Logic block diagram
LBO
CLK
ADV
ADSC
ADSP
A[19:0]
20
CLK
CE
CLR
Q0
Burst logic
Q1
2
2
D
Q
CE
Address
register
CLK
D
DQ
d
Q
Byte write
registers
CLK
D
DQ
Q
c
Byte write
registers
CLK
D
DQ
b
Q
Byte write
registers
CLK
D
DQ
a
Q
Byte write
registers
CLK
D
Enable
CE
register
CLK
Q
1M × 32/36
Memory
array
20
18
20
32/36
32/36
GWE
BWE
BW
d
BW
c
BW
b
BW
a
CE0
CE1
CE2
4
OE
Output
registers
CLK
Input
registers
CLK
ZZ
Power
down
D
Enable
Q
delay
register
CLK
32/36
DQ[a:d]
OE
Selection guide
Minimum cycle time
Maximum clock frequency
Maximum clock access time
Maximum operating current
Maximum standby current
Maximum CMOS standby current (DC)
-200
5
200
3.1
450
170
90
-166
6
166
3.5
400
150
90
-133
7.5
133
3.8
350
140
90
Units
ns
MHz
ns
mA
mA
mA
11/29/04, v.2.8
Alliance Semiconductor
1 of 27
Copyright © Alliance Semiconductor. All rights reserved.
AS7C331MPFS32A
AS7C331MPFS36A
®
32 Mb Synchronous SRAM products list
1,2
Org
2MX18
1MX32
1MX36
2MX18
1MX32
1MX36
2MX18
1MX32
1MX36
2MX18
1MX32
1MX36
2MX18
1MX32
1MX36
Part Number
AS7C332MPFS18A
AS7C331MPFS32A
AS7C331MPFS36A
AS7C332MPFD18A
AS7C331MPFD32A
AS7C331MPFD36A
AS7C332MFT18A
AS7C331MFT32A
AS7C331MFT36A
AS7C332MNTD18A
AS7C331MNTD32A
AS7C331MNTD36A
AS7C332MNTF18A
AS7C331MNTF32A
AS7C331MNTF36A
Mode
PL-SCD
PL-SCD
PL-SCD
PL-DCD
PL-DCD
PL-DCD
FT
FT
FT
NTD-PL
NTD-PL
NTD-PL
NTD-FT
NTD-FT
NTD-FT
Speed
200/166/133 MHz
200/166/133 MHz
200/166/133 MHz
200/166/133 MHz
200/166/133 MHz
200/166/133 MHz
7.5/8.5/10 ns
7.5/8.5/10 ns
7.5/8.5/10 ns
200/166/133 MHz
200/166/133 MHz
200/166/133 MHz
7.5/8.5/10 ns
7.5/8.5/10 ns
7.5/8.5/10 ns
1 Core Power Supply: VDD = 3.3V + 0.165V
2 I/O Supply Voltage: VDDQ = 3.3V + 0.165V for 3.3V I/O
VDDQ = 2.5V + 0.125V for 2.5V I/O
PL-SCD
PL-DCD
FT
NTD
1
-PL
NTD-FT
:
:
:
:
:
Pipelined Burst Synchronous SRAM - Single Cycle Deselect
Pipelined Burst Synchronous SRAM - Double Cycle Deselect
Flow-through Burst Synchronous SRAM
Pipelined Burst Synchronous SRAM with NTD
TM
Flow-through Burst Synchronous SRAM with NTD
TM
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.
11/29/04, v.2.8
Alliance Semiconductor
2 of 27
AS7C331MPFS32A
AS7C331MPFS36A
®
Functional description
The AS7C331MPFS32A/36A is a high-performance CMOS 32-Mbit Synchronous Static Random Access Memory (SRAM)
device organized as 1,048,576 words x 32/36. 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 200,166and 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 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 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 single-
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 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.
The AS7C331MPFS32A/36A 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 TQFP and 165-ball BGA.
TQFP and BGA capacitance
Parameter
Input capacitance
I/O capacitance
* Guaranteed not tested
Symbol
C
IN*
C
I/O*
Test conditions
V
IN
= 0V
V
OUT
= 0V
Min
-
-
Max
5
7
Unit
pF
pF
TQFP and BGA thermal resistance
Description
Thermal resistance
(junction to ambient)
1
Thermal resistance
(junction to top of case)
1
1 This parameter is sampled
Conditions
Test conditions follow standard test methods
and procedures for measuring thermal
impedance, per EIA/JESD51
1–layer
4–layer
Symbol
θ
JA
θ
JA
θ
JC
Typical
40
22
8
Units
°C/W
°C/W
°C/W
11/29/04, v.2.8
Alliance Semiconductor
5 of 27