CY7C4282V
CY7C4292V
Pin Definitions
Signal Name
Description
I/O
Description
D
Data Inputs
Data Outputs
Write Enable
I
O
I
Data Inputs for 9-bit bus.
Data Outputs for 9-bit bus.
0−8
Q
0−8
WEN
The only write enable when device is configured to have programmable flags. Data is
written on a LOW-to-HIGH transition of WCLK when WEN is asserted and FF is HIGH.
REN
Read Enable
Write Clock
Read Clock
I
I
I
Enables the device for Read operation. REN must be asserted LOW to allow a Read
operation.
WCLK
RCLK
The rising edge clocks data into the FIFO when WEN is LOW and the FIFO is not Full.
When LD is asserted, WCLK writes data into the programmable flag-offset register.
The rising edge clocks data out of the FIFO when REN is LOW and the FIFO is not Empty.
When LD is LOW, RCLK reads data out of the programmable flag-offset register.
EF
Empty Flag
Full Flag
O
O
O
When EF is LOW, the FIFO is empty. EF is synchronized to RCLK.
When FF is LOW, the FIFO is full. FF is synchronized to WCLK.
FF
PAE
Programmable
Almost Empty
When PAE is LOW, the FIFO is almost empty based on the almost empty offset value pro-
grammed into the FIFO. PAE is synchronized to RCLK.
PAF/XO
FL/RT
Programmable
Almost Full/
Expansion
Output
O
Dual-Mode Pin:
Cascaded - Connected to XI of next device.
Not Cascaded - When PAFis LOW, theFIFO isalmost full based on the almost full offset value
programmed into the FIFO. PAF is synchronized to WCLK.
First Load/
Retransmit
I
Dual-Mode Pin:
Cascaded - The first device in the daisy chain will haveFL tied to V ; all other devices
SS
will have FL tied to V . In standard mode or width expansion, FL is tied to V
CC
SS
on all devices.
Not Cascaded - Retransmit function is available in stand-alone mode by strobing
RT.
XI/LD
Expansion In-
put/Load
I
Dual-Mode Pin:
Cascaded - Connected to XO of previous device.
Not Cascaded - LD is used to write or read the programmable flag offset registers. LD
must be asserted LOW during reset to enable standalone or width expansion operation.
If programmable offset register access is not required, LD can be tied to RS directly.
OE
RS
Output Enable
Reset
I
I
When OE is LOW, the FIFO’s data outputs drive the bus to which they are connect-
ed. If OE is HIGH, the FIFO’s outputs are in High Z (high-impedance) state.
Resets device to empty condition. A reset is required before an initial read or write
operation after power-up.
Static Discharge Voltage ........................................... >2001V
(per MIL-STD-883, Method 3015)
Maximum Ratings
(Above which the useful life may be impaired. For user guide-
lines, not tested.)
Latch-Up Current..................................................... >200 mA
Storage Temperature ....................................... −65°C to +150°C
Operating Range
Ambient Temperature with
Power Applied.................................................... −55°C to +125°C
Ambient
Temperature
[2]
Range
V
CC
Supply Voltage to Ground Potential..........−0.5V to V +0.5V
CC
Commercial
0°C to +70°C
3.3V + /−300mV
3.3V + /−300mV
DC Voltage Applied to Outputs
[1]
Industrial
−40°C to +85°C
in High Z State..............................................−0.5V to V +0.5V
CC
Notes:
DC Input Voltage .........................................−0.5V to V +0.5V
CC
1. TA is the “instant on” case temperature.
2. VCC Range for commercial -10 ns is 3.3V ± 150 mV.
Output Current into Outputs (LOW) .............................20 mA
3
CYPRESS [ CYPRESS ]
