• Fast clock-to-output times, 6.5 ns (133 MHz version)
• Provides high-performance 2-1-1-1 access rate
• User selectable burst counter supporting Intel
interleaved or linear burst sequences
• Separate processor and controller address strobes
• Synchronous self timed write
• Asynchronous output enable
• CY7C1381DV25/CY7C1383DV25 available in
JEDEC-standard Pb-free 100-pin TQFP, Pb-free and non
Pb-free 165-ball FBGA package.
CY7C1381FV25/CY7C1383FV25 available in Pb-free and
non Pb-free 119-ball BGA package
• IEEE 1149.1 JTAG-Compatible Boundary Scan
• ZZ sleep mode option
)
DD
)
®
Pentium®
Functional Description
[1]
The CY7C1381DV25/CY7C1383DV25/CY7C1381FV25/
CY7C1383FV25 is a 2.5V, 512K x 36 and 1M x 18
synchronous flow through SRAMs, designed to interface with
high-speed microprocessors with minimum glue logic.
Maximum access delay from clock rise is 6.5 ns (133 MHz
version). A 2-bit on-chip counter captures the first address in
a burst and increments the address automatically for the rest
of the burst access. All synchronous inputs are gated by
registers controlled by a positive edge triggered clock input
(CLK). The synchronous inputs include all addresses, all data
inputs, address pipelining chip enable (CE
chip enables (CE2 and CE
[2]
), burst control inputs (ADSC,
3
), depth expansion
1
ADSP, and ADV), write enables (BWx, and BWE), and global
write (GW
). Asynchronous inputs include the output enable
(OE) and the ZZ pin.
The
CY7C1383FV25
CY7C1381DV25/CY7C1383DV25/CY7C1381FV25/
allows interleaved or linear burst sequences,
selected by the MODE input pin. A HIGH selects an
interleaved burst sequence, while a LOW selects a linear burst
sequence. Burst accesses can be initiated with the processor
) or the cache controller address strobe
address strobe
(ADSP
(ADSC) inputs. Address advancement is controlled by the
address advancement (ADV) input.
Addresses and chip enables are registered at rising edge of
clock when either address strobe processor (ADSP
) or
address strobe controller (ADSC) are active. Subsequent
burst addresses can be internally generated as controlled by
the advance pin (ADV
).
The CY7C1381DV25/CY7C1383DV25/CY7C1381FV25/
CY7C1383FV25 operates from a +2.5V core power supply
while all outputs also operate with a +2.5 supply. All inputs and
outputs are JEDEC-standard and JESD8-5-compatible.
Selection Guide
133 MHz100 MHzUnit
Maximum Access Time6.58.5ns
Maximum Operating Current210175mA
Maximum CMOS Standby Current7070mA
Notes
1. For best practices or recommendations, please refer to the Cypress application note AN1064, SRAM System Design Guidelines on www.cypress.com.
Address inputs used to select one of the address locations. Sampled at the rising edge
of the CLK if ADSP
A
feed the 2-bit counter.
[1:0]
or ADSC is active LOW, and CE1, CE2, and CE
Byte write select inputs, active LOW. Qualified with BWE to conduct byte writes to the
SRAM. Sampled on the rising edge of CLK.
Global write enable input, active LOW. When asserted LOW on the rising edge of CLK, a
global write is conducted (all bytes are written, regardless of the values on BW
Clock input. Used to capture all synchronous inputs to the device. Also used to increment
the burst counter when ADV is asserted LOW, during a burst operation.
Chip enable 1 input, active LOW. Sampled on the rising edge of CLK. Used in conjunction
with CE
and CE
2
[2]
to select or deselect the device. ADSP is ignored if CE1 is HIGH. CE1
3
is sampled only when a new external address is loaded.
Chip enable 2 input, active HIGH. Sampled on the rising edge of CLK. Used in conjunction
with CE
and CE
1
[2]
to select or deselect the device. CE2 is sampled only when a new
3
external address is loaded.
Chip enable 3 input, active LOW. Sampled on the rising edge of CLK. Used in conjunction
with CE
and CE2 to select or deselect the device. CE3 is sampled only when a new external
1
address is loaded.
Output enable, asynchronous input, active LOW. Controls the direction of the IO pins.
When LOW, the IO pins behave as outputs. When deasserted HIGH, IO pins are tri-stated,
and act as input data pins. OE
is masked during the first clock of a read cycle when emerging
from a deselected state.
Advance input signal. Sampled on the rising edge of CLK. When asserted, it automatically
increments the address in a burst cycle.
Address strobe from processor, sampled on the rising edge of CLK, active LOW. When
asserted LOW, addresses presented to the device are captured in the address registers.
A
are also loaded into the burst counter. When ADSP and ADSC are both asserted, only
[1:0]
ADSP
is recognized. ASDP is ignored when CE1 is deasserted HIGH.
Address strobe from controller, sampled on the rising edge of CLK, active LOW. When
asserted LOW, addresses presented to the device are captured in the address registers.
A
are also loaded into the burst counter. When ADSP and ADSC are both asserted, only
[1:0]
ADSP
is recognized
.
Byte write enable input, active LOW. Sampled on the rising edge of CLK. This signal must
be asserted LOW to conduct a byte write.
ZZ sleep input. This active HIGH input places the device in a non-time critical sleep
condition with data integrity preserved. For normal operation, this pin has to be LOW or left
floating. ZZ pin has an internal pull down.
Bidirectional data IO lines. As inputs, they feed into an on-chip data register that is triggered
by the rising edge of CLK. As outputs, they deliver the data contained in the memory location
specified by the addresses presented during the previous clock rise of the read cycle. The
direction of the pins is controlled by OE
outputs. When HIGH, DQ
and DQPX are placed in a tri-state condition.The outputs are
s
. When OE is asserted LOW, the pins behave as
automatically tri-stated during the data portion of a write sequence, during the first clock
when emerging from a deselected state, and when the device is deselected, regardless of
the state of OE
.
Bidirectional data parity IO lines. Functionally, these signals are identical to DQs. During
write sequences, DQP
MODEInput-StaticSelects burst order. When tied to GND selects linear burst sequence. When tied to V
left floating selects interleaved burst sequence. This is a strap pin and must remain static
during device operation. Mode pin has an internal pull up.
V
DD
V
DDQ
V
SS
V
SSQ
TDOJTAG serial output
TDIJTAG serial input
TMSJTAG serial input
TCKJTAG-
NC, NC/(36M,
72M, 144M,
288M, 576M,
1G)
V
/DNUGround/DNUThis pin can be connected to ground or can be left floating.
SS
Power Supply Power supply inputs to the core of the device.
IO Power Supply Power supply for the IO circuitry.
GroundGround for the core of the device.
IO GroundGround for the IO circuitry.
Serial data-out to the JTAG circuit. Delivers data on the negative edge of TCK. If the JTAG
Synchronous
feature is not used, this pin can be left unconnected. This pin is not available on TQFP
packages.
Serial data-in to the JTAG circuit. Sampled on the rising edge of TCK. If the JTAG feature
Synchronous
is not used, this pin can be left floating or connected to V
pin is not available on TQFP packages.
Serial data-in to the JTAG circuit. Sampled on the rising edge of TCK. If the JTAG feature
Synchronous
is not used, this pin can be disconnected or connected to V
TQFP packages.
Clock input to the JTAG circuitry. If the JTAG feature is not used, this pin must be
Clock
connected to V
. This pin is not available on TQFP packages.
SS
-No Connects. Not internally connected to the die. 36M, 72M, 144M, 288M, 576M, and 1G
are address expansion pins and are not internally connected to the die.
through a pull up resistor. This
DD
. This pin is not available on
DD
DD
or
Functional Overview
All synchronous inputs pass through input registers controlled
by the rising edge of the clock. Maximum access delay from
the clock rise (t
The CY7C1381DV25/CY7C1383DV25/CY7C1381FV25/
CY7C1383FV25 supports secondary cache in systems using
a linear or interleaved burst sequence. The interleaved burst
order supports Pentium
burst sequence is suited for processors that use a linear burst
sequence. The burst order is user selectable, and is
determined by sampling the MODE input. Accesses can be
initiated with either the processor address strobe (ADSP
the controller address strobe (ADSC
through the burst sequence is controlled by the ADV
two-bit on-chip wraparound burst counter captures the first
address in a burst sequence and automatically increments the
address for the rest of the burst access.
Byte write operations are qualified with the byte write enable
) and byte write select (BWX) inputs. A global write
(BWE
enable (GW) overrides all byte write inputs and writes data to
all four bytes. All writes are simplified with on-chip
synchronous self timed write circuitry.
Three synchronous chip selects (CE
asynchronous output enable (OE
) is 6.5 ns (133 MHz device).
CDV
®
and i486™ processors. The linear
). Address advancement
, CE2, CE
1
) provide for easy bank
[2]
3
) or
input. A
) and an
selection and output tri-state control. ADSP is ignored if CE
is HIGH.
Single Read Accesses
A single read access is initiated when the following conditions
are satisfied at clock rise: (1) CE
asserted active, and (2) ADSP
the access is initiated by ADSC
, CE2, and CE
1
or ADSC is asserted LOW (if
, the write inputs must be
[2]
3
are all
deserted during this first cycle). The address presented to the
address inputs is latched into the address register and the
burst counter and/or control logic, and presented to the
memory core. If the OE
input is asserted LOW, the requested
data will be available at the data outputs with a maximum to
after clock rise. ADSP is ignored if CE1 is HIGH.
t
CDV
Single Write Accesses Initiated by ADSP
This access is initiated when the following conditions are
satisfied at clock rise: (1) CE
active, and (2) ADSP
, CE2, CE
1
is asserted LOW. The addresses
[2]
are all asserted
3
presented are loaded into the address register and the burst
inputs (GW
cycle. If the write inputs are asserted active (see Truth Table
for Read/Write
, BWE, and BWX) are ignored during this first clock
[4, 9]
on page 10 for appropriate states that
indicate a write) on the next clock rise, the appropriate data will
be latched and written into the device. Byte writes are allowed.
All IOs are tri-stated during a byte write. As this is a common
IO device, the asynchronous OE
and the IOs must be tri-stated prior to the presentation of data
to DQs. As a safety precaution, the data lines are tri-stated
once a write cycle is detected, regardless of the state of OE.
Single Write Accesses Initiated by ADSC
This write access is initiated when the following conditions are
satisfied at clock rise: (1) CE1, CE2, and CE
asserted active, (2) ADSC
is asserted LOW, (3) ADSP is
deserted HIGH, and (4) the write input signals (GW
[2]
are all
3
, BWE, and
BWX) indicate a write access. ADSC is ignored if ADSP is
active LOW.
The addresses presented are loaded into the address register
and the burst counter, the control logic, or both, and delivered
to the memory core. The information presented to DQ
will be
X
written into the specified address location. Byte writes are
allowed. All IOs are tri-stated when a write is detected, even a
byte write. Since this is a common IO device, the
asynchronous OE
input signal must be deasserted and the IOs
must be tri-stated prior to the presentation of data to DQs. As
a safety precaution, the data lines are tri-stated once a write
cycle is detected, regardless of the state of OE
.
Burst Sequences
The CY7C1381DV25/CY7C1383DV25/CY7C1381FV25/
CY7C1383FV25 provides an on-chip two-bit wraparound burst
counter inside the SRAM. The burst counter is fed by A
[1:0]
and can follow either a linear or interleaved burst order. The
burst order is determined by the state of the MODE input. A
LOW on MODE will select a linear burst sequence. A HIGH on
MODE will select an interleaved burst order. Leaving MODE
unconnected will cause the device to default to a interleaved
burst sequence.
Sleep Mode
The ZZ input pin is an asynchronous input. Asserting ZZ
places the SRAM in a power conservation sleep mode. Two
clock cycles are required to enter into or exit from this sleep
mode. While in this mode, data integrity is guaranteed.
Accesses pending when entering the sleep mode are not
considered valid nor is the completion of the operation
guaranteed. The device must be deselected prior to entering
the sleep mode. CE
, CE2, CE
1
remain inactive for the duration of t
[2]
, ADSP, and ADSC must
3
after the ZZ input
ZZREC
returns LOW.
Interleaved Burst Address Table
(MODE = Floating or V
First
Address
A1: A0
00011011
01001110
10110001
11100100
Second
Address
A1: A0
DD
)
Third
Address
A1: A0
Linear Burst Address Table (MODE = GND)
First
,
Address
A1: A0
00011011
01101100
10110001
11000110
Second
Address
A1: A0
Third
Address
A1: A0
Fourth
Address
A1: A0
Fourth
Address
A1: A0
ZZ Mode Electrical Characteristics
ParameterDescriptionTest ConditionsMin.Max.Unit
I
DDZZ
t
ZZS
t
ZZREC
t
ZZI
t
RZZI
Document #: 38-05547 Rev. *EPage 8 of 28
Sleep mode standby currentZZ > VDD – 0.2V80mA
Device operation to ZZZZ > VDD – 0.2V2t
ZZ recovery timeZZ < 0.2V2t
CYC
ZZ active to sleep currentThis parameter is sampled2t
CYC
CYC
ns
ns
ns
ZZ Inactive to exit sleep currentThis parameter is sampled0ns
6. The DQ pins are controlled by the current cycle and the OE
7. The SRAM always initiates a read cycle when ADSP
8. OE
= L when any one or more byte write enable signals, and BWE = L or GW = L. WRITE = H when all byte write enable signals, BWE, GW = H.
the ADSP
care for the remainder of the write cycle.
inactive or when the device is deselected, and all data bits behave as output when OE
or with the assertion of ADSC. As a result, OE must be driven HIGH prior to the start of the write cycle to allow the outputs to tri-state. OE is a don't
is asynchronous and is not sampled with the clock rise. It is masked internally during write cycles. During a read cycle all data bits are tri-state when OE is
signal. OE is asynchronous and is not sampled with the clock.
is asserted, regardless of the state of GW, BWE, or BWX. Writes may occur only on subsequent clocks after
is active (LOW).
Document #: 38-05547 Rev. *EPage 9 of 28
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