CY7C0832V-133AC Cypress Semiconductor Corp, CY7C0832V-133AC Datasheet - Page 8

• Manufacturer Part Number: CY7C0832V-133AC
• Manufacturer: Cypress Semiconductor Corp

Specifications of CY7C0832V-133AC

• Density: 4.5Mb
• Access Time (max): 4.4ns
• Sync/async: Synchronous
• Architecture: SDR
• Clock Freq (max): 133MHz
• Operating Supply Voltage (typ): 3.3V
• Address Bus: 18b
• Package Type: TQFP
• Operating Temp Range: 0C to 70C
• Number Of Ports: 2
• Supply Current: 300mA
• Operating Supply Voltage (min): 3.135V
• Operating Supply Voltage (max): 3.465V
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 120
• Word Size: 18b
• Number Of Words: 256K
• Lead Free Status / Rohs Status: Not Compliant

Document #: 38-06059 Rev. *K
Retransmit
Retransmit is a feature that allows the Read of a block of
memory more than once without the need to reload the initial
address. This eliminates the need for external logic to store
and route data. It also reduces the complexity of the system
design and saves board space. An internal “mirror register” is
used to store the initially loaded address counter value. When
the counter unmasked portion reaches its maximum value set
by the mask register, it wraps back to the initial value stored in
this “mirror register.” If the counter is continuously configured
in increment mode, it increments again to its maximum value
and wraps back to the value initially stored into the “mirror
register.” Thus, the repeated access of the same data is
allowed without the need for any external logic.
Mask Reset Operation
The mask register is reset to all “1s,” which unmasks every bit
of the counter. Master reset (MRST) also resets the mask
register to all “1s.”
Mask Load Operation
The mask register is loaded with the address value presented
at the address lines. Not all values permit correct increment
PRELIMINARY
operations. Permitted values are of the form 2
From the most significant bit to the least significant bit,
permitted values have zero or more “0s,” one or more “1s,” or
one “0.” Thus 3FFFF, 003FE, and 00001 are permitted values,
but 3F0FF, 003FC, and 00000 are not.
Mask Readback Operation
The internal value of the mask register can be read out on the
address lines. Readback is pipelined; the address will be valid
t
readback occurs while the port is enabled (CE0 LOW and CE1
HIGH), the data lines (DQs) will be three-stated. Figure 1
shows a block diagram of the operation.
Counting by Two
When the least significant bit of the mask register is “0,” the
counter increments by two. This may be used to connect the
x18 devices as a 36-bit single port SRAM in which the counter
of one port counts even addresses and the counter of the other
port counts odd addresses. This even-odd address scheme
stores one half of the 36-bit data in even memory locations,
and the other half in odd memory locations.
CM2
after the next rising edge of the port’s clock. If mask
CY7C0830V/CY7C0831V
CY7C0832V/CY7C0833V
CY7C0837V
n
– 1 or 2
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n
– 2.