CY7C1471V25
CY7C1473V25
CY7C1475V25
Document #: 38-05287 Rev. *I Page 10 of 32
Because the CY7C1471V25, CY7C1473V25, and
CY7C1475V25 are common IO devices, data must not be
driven into the device while the outputs are active. The OE can
be deasserted HIGH before presenting data to the DQs and
DQPX inputs. This tri-states the output drivers. As a safety
precaution, DQs and DQPX are automatically tri-stated during
the data portion of a write cycle, regardless of the state of OE.
Burst Write Accesses
The CY7C1471V25, CY7C1473V25, and CY7C1475V25
have an on-chip burst counter that enables the user to supply
a single address and conduct up to four Write operations
without reasserting the address inputs. ADV/LD must be
driven LOW to load the initial address, as described in the
Single Write Access section. When ADV/LD is dr iven HIGH on
the subsequent clock rise, the Chip Enables (CE1, CE2, and
CE3) and WE inputs are ignored and the burst counter is incre-
mented. The correct BWX inputs must be driven in each cycle
of the Burst Write, to write the correct bytes of data.
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 before entering
the “sleep” mode. CE1, CE2, and CE3, must remain inactive
for the duration of tZZREC after the ZZ input returns LOW.
Interleaved Burst Address Table (MODE = Floating or VDD)
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
ZZ Mode Electrical Characteristics
Parameter Description Test Conditions Min Max Unit
IDDZZ Sleep mode standby current ZZ > VDD – 0.2V 120 mA
tZZS Device operation to ZZ ZZ > VDD – 0.2V 2tCYC ns
tZZREC ZZ recovery time ZZ < 0.2V 2tCYC ns
tZZI ZZ active to sleep current This parameter is sampled 2tCYC ns
tRZZI ZZ Inactive to exit sleep current This parameter is sampled 0 ns
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