CY7C1361C
CY7C1363C
Document #: 38-05541 Rev. *F
Page 9 of 31
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
CDV
) is 6.5 ns (133-MHz device).
The CY7C1361C/CY7C1363C supports secondary cache in
systems utilizing either a linear or interleaved burst sequence.
The interleaved burst order supports Pentium and i486™
processors. The linear burst sequence is suited for processors
that utilize 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) or the Controller Address Strobe
(ADSC). Address advancement through the burst sequence is
controlled by the ADV input. A 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
(BWE) and Byte Write Select (BW
X
) inputs. A Global Write
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
1
, CE
2
, CE
3
[2]
) and an
asynchronous Output Enable (OE) provide for easy bank
selection and output tri-state control. ADSP is ignored if CE
1
is HIGH.
Single Read Accesses
A single read access is initiated when the following conditions
are satisfied at clock rise: (1) CE
1
, CE
2
, and CE
3
[2]
are all
asserted active, and (2) ADSP or ADSC is asserted LOW (if
the access is initiated by ADSC, the write inputs must be
deasserted during this first cycle). The address presented to
the address inputs is latched into the address register and the
burst counter/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 a maximum to t
CDV
after clock
rise. ADSP is ignored if CE
1
is HIGH.
Single Write Accesses Initiated by ADSP
This access is initiated when the following conditions are
satisfied at clock rise: (1) CE
1
, CE
2
, CE
3
[2]
are all asserted
active, and (2) ADSP is asserted LOW. The addresses
presented are loaded into the address register and the burst
inputs (GW, BWE, and BW
X
)are ignored during this first clock
cycle. If the write inputs are asserted active (see Write Cycle
Descriptions table 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 I/Os are
tri-stated during a byte write.Since this is a common I/O
device, the asynchronous OE input signal must be deasserted
and the I/Os 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) CE
1
, CE
2
, and CE
3
[2]
are all asserted
active, (2) ADSC is asserted LOW, (3) ADSP is deasserted
HIGH, and (4) the write input signals (GW, BWE, and BW
X
)
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/control logic and delivered to the
memory core. The information presented to DQ
[A:D]
will be
written into the specified address location. Byte writes are
allowed. All I/Os are tri-stated when a write is detected, even
a byte write. Since this is a common I/O device, the
asynchronous OE input signal must be deasserted and the
I/Os must be tri-stated prior to the presentation of data to DQ
s
.
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 CY7C1361C/CY7C1363C 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
1
, CE
2
, CE
3
[2]
, ADSP, and ADSC must
remain inactive for the duration of t
ZZREC
after the ZZ input
returns LOW.
Interleaved Burst Address Table
(MODE = Floating or V
DD
)
First
Address
A1: A0
Second
Address
A1: A0
Third
Address
A1: A0
Fourth
Address
A1: A0
00
01
10
11
01
00
11
10
10
11
00
01
11
10
01
00
Linear Burst Address Table (MODE = GND)
First
Address
A1: A0
Second
Address
A1: A0
Third
Address
A1: A0
Fourth
Address
A1: A0
00
01
10
11
01
10
11
00
10
11
00
01
11
00
01
10
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