Cypress CY7C1462AV33 - Manual (Page 8)

CY7C1460AV33
CY7C1462AV33
CY7C1464AV33
Document #: 38-05353 Rev. *D Page 8 of 27
counter is incremented. The correct BW (BW
a,b,c,d,e,f,g,h
for
CY7C1464AV33, BW
a,b,c,d
for CY7C1460AV33 and BW
a,b
for
CY7C1462AV33) inputs must be driven in each cycle of the
burst write in order 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 prior to entering
the “sleep” mode. CE
1
, CE
2
, and CE
3
, must remain inactive
for the duration of t
ZZREC
after the ZZ input returns LOW.
Interleaved Burst Address Table
(MODE = Floating or V
DD
)
First
Address
Second
Address
Third
Address
Fourth
Address
A1,A0 A1,A0 A1,A0 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
Second
Address
Third
Address
Fourth
Address
A1,A0 A1,A0 A1,A0 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
I
DDZZ
Sleep mode standby current ZZ
> V
DD
− 0.2V
100 mA
t
ZZS
Device operation to ZZ ZZ
> V
DD
− 0.2V
2t
CYC
ns
t
ZZREC
ZZ recovery time ZZ
< 0.2V
2t
CYC
ns
t
ZZI
ZZ active to sleep current This parameter is sampled 2t
CYC
ns
t
RZZI
ZZ Inactive to exit sleep current This parameter is sampled 0 ns
Truth Table [1, 2, 3, 4, 5, 6, 7]
Operation
Address
Used CE ZZ ADV/LD WE BW
x
OE CEN CLK DQ
Deselect Cycle None H L L X X X L L-H Tri-State
Continue
Deselect Cycle None X L H X X X L L-H Tri-State
Read Cycle
(Begin Burst) External L L L H X L L L-H Data Out (Q)
Read Cycle
(Continue Burst) Next X L H X X L L L-H Data Out (Q)
NOP/Dummy Read
(Begin Burst) External L L L H X H L L-H Tri-State
Dummy Read
(Continue Burst) Next X L H X X H L L-H Tri-State
Notes:
1. X = “Don't Care”, H = Logic HIGH, L = Logic LOW, CE stands for ALL Chip Enables active. BWx = L signifies at least one Byte Write Select is active, BWx =
Valid signifies that the desired byte write selects are asserted, see Write Cycle Description table for details.
2. Write is defined by WE and BW
X
. See Write Cycle Description table for details.
3. When a write cycle is detected, all I/Os are tri-stated, even during byte writes.
4. The DQ and DQP pins are controlled by the current cycle and the OE signal.
5. CEN = H inserts wait states.
6. Device will power-up deselected and the I/Os in a tri-state condition, regardless of OE.
7. OE is asynchronous and is not sampled with the clock rise. It is masked internally during write cycles.During a read cycle DQ
s
and DQP
X
= Tri-state when OE
is inactive or when the device is deselected, and DQ
s
=data when OE is active.
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