CY7C1345GDocument Number: 38-05517 Rev. *E Page 7 of 20
Burst Sequences
The CY7C1345G provides an on-chip two-bit wrap around burst
counter inside the SRAM. The burst counter is fed by A[1:0] and
follows either a linear or interleaved burst order. The burst order
is determined by the state of the MODE input. A LOW on MODE
selects a linear burst sequence. A HIGH on MODE selects an
interleaved burst order. Leaving MODE unconnected causes 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. 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 is
deselected prior to entering the sleep mode. CEs, ADSP, and
ADSC must remain inactive for the duration of tZZREC after the
ZZ input returns LOW.
Table 1. 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
Table 2. 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 40 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