Pin definitions – Cypress CY7C1344H User Manual
Page 3
CY7C1344H
Document #: 001-00211 Rev. *B
Page 3 of 15
Pin Definitions
Name
I/O
Description
A0, A1,
A
Input-
Synchronous
Address Inputs used to select one of the 64K address locations. Sampled at the rising edge of the
CLK if ADSP or ADSC is active LOW, and CE
1
,
CE
2
, and
CE
3
are sampled active. A
[1:0]
feed the 2-bit
counter.
BW
A
,
BW
B
BW
C
,
BW
D
Input-
Synchronous
Byte Write Select Inputs, active LOW. Qualified with BWE to conduct Byte Writes to the SRAM.
Sampled on the rising edge of CLK.
GW
Input-
Synchronous
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
[A:D]
and BWE).
BWE
Input-
Synchronous
Byte Write Enable Input, active LOW. Sampled on the rising edge of CLK. This signal must be asserted
LOW to conduct a Byte Write.
CLK
Input-Clock
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.
CE
1
Input-
Synchronous
Chip Enable 1 Input, active LOW. Sampled on the rising edge of CLK. Used in conjunction with CE
2
and CE
3
to select/deselect the device. ADSP is ignored if CE
1
is HIGH. CE
1
is sampled only when a
new external address is loaded.
CE
2
Input-
Synchronous
Chip Enable 2 Input, active HIGH. Sampled on the rising edge of CLK. Used in conjunction with CE
1
and CE
3
to select/deselect the device. CE
2
is sampled only when a new external address is loaded.
CE
3
Input-
Synchronous
Chip Enable 3 Input, active LOW. Sampled on the rising edge of CLK. Used in conjunction with CE
1
and
CE
2
to select/deselect the device. CE
3
is sampled only when a new external address is loaded.
OE
Input-
Asynchronous
Output Enable, asynchronous input, active LOW. Controls the direction of the I/O pins. When LOW,
the I/O pins behave as outputs. When deasserted HIGH, I/O 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.
ADV
Input-
Synchronous
Advance Input signal, sampled on the rising edge of CLK. When asserted, it automatically incre-
ments the address in a burst cycle.
ADSP
Input-
Synchronous
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
[1:0]
are also loaded
into the burst counter. When ADSP and ADSC are both asserted, only ADSP is recognized. ASDP is
ignored when CE
1
is deasserted HIGH
ADSC
Input-
Synchronous
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
[1:0]
are also loaded
into the burst counter. When ADSP and ADSC are both asserted, only ADSP is recognized.
ZZ
Input-
Asynchronous
ZZ “sleep” Input, active HIGH. When asserted HIGH 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.
DQs
DQP
A,
DQP
B
DQP
C,
DQP
D
I/O-
Synchronous
Bidirectional Data I/O 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. When OE is asserted LOW, the pins behave as outputs. When HIGH, DQs and
DQP
[A:D]
are placed in a tri-state condition.
V
DD
Power
Supply
Power supply inputs to the core of the device.
V
SS
Ground
Ground for the core of the device.
V
DDQ
I/O Power
Supply
Power supply for the I/O circuitry.
V
SSQ
I/O Ground
Ground for the I/O circuitry.
MODE
Input-
Static
Selects Burst Order. When tied to GND selects linear burst sequence. When tied to V
DD
or left floating
selects interleaved burst sequence. This is a strap pin and should remain static during device operation.
Mode pin has an internal pull-up.
NC
No Connects. Not Internally connected to the die. 4M, 9M,1 8M, 72M, 144M, 288M, 576M, and 1G are
address expansion pins and are not internally connected to the die.