CY7C027V/028V
CY7C037V/038V
2
Functional Description
The CY7C027V/028V and CY7037V/038V are low-power
CMOS 32K, 64K x 16/18 dual-port static RAMs. Various arbi-
tration schemes are included on the devices to handle situa-
tions when multiple processors access the same piece of data.
Two ports are provided, permitting independent, asynchro-
nous access for reads and writes to any location in memory.
The devices can be utilized as stand-alone 16/18-bit dual-port
static RAMs or multiple devices can be combined in order to
function as a 32/36-bit or wider master/slave dual-port static
RAM. An M/S
pin is provided for implementing 32/36-bit or
wider memory applications without the need for separate mas-
ter and slave devices or additional discrete logic. Application
areas include interprocessor/multiprocessor designs, commu-
nications status buffering, and dual-port video/graphics mem-
ory.
Each port has independent control pins: chip enable (CE
),
read or write enable (R/W
), and output enable (OE). Two flags are
provided on each port (BUSY and INT). BUSY signals that the port
is trying to access the same location currently being accessed by the
other port. The interrupt flag (INT
) permits communication between
ports or systems by means of a mail box. The semaphores are used
to pass a flag, or token, from one port to the other to indicate that a
shared resource is in use. The semaphore logic is comprised of eight
shared latches. Only one side can control the latch (semaphore) at
any time. Control of a semaphore indicates that a shared resource is
in use. An automatic power-down feature is controlled independently
on each port by a chip select (CE
) pin.
The CY7C027V/028V and CY7037V/038V are available in
100-pin Thin Quad Plastic Flatpacks (TQFP).
Pin Configurations
100-Pin TQFP (Top View)
Note:
5. This pin is NC for CY7C027V.
1
3
2
92 91 90 848587 868889 83 82 81 7678 77798093949596979899100
59
60
61
67
66
64
65
63
62
68
69
70
75
73
74
72
71
A9R
A10R
A11R
A12R
A13R
A14R
UBR
NC
LBR
CE1R
SEMR
OER
GND
NC
A15R
GND
R/WR
GND
I/O15R
I/O14R
I/O13R
I/O12R
I/O11R
I/O10R
CE0R
58
57
56
55
54
53
52
51
CY7C027V (32K x 16)
A9L
A10L
A11L
A12L
A13L
A14L
UBL
NC
LBL
CE1L
SEML
OEL
GND
NC
A15L
VCC
R/WL
GND
I/O15L
I/O14L
I/O13L
I/O12L
I/O11L
I/O10L
CE0L
17
16
15
9
10
12
11
13
14
8
7
6
4
5
18
19
20
21
22
23
24
25
A8L
A7L
A6L
A5L
A4L
A3L
INTL
A1L
NC
GND
M/S
A0R
A1R
A0L
A2L
BUSYR
INTR
A2R
A3R
A4R
A5R
A6R
A7R
A8R
BUSYL
34 35 36 424139 403837 43 44 45 5048 494746
NC
I/O9R
I/O8R
I/O7R
VCC
I/O6R
I/01R
I/O4R
I/O2R
GND
I/O0L
I/O2L
I/O3L
I/O3R
I/O5R
I/O1L
GND
I/O4L
I/O5L
I/O6L
I/O7L
VCC
I/O8L
I/O9L
I/O0R
3332313029282726
CY7C028V (64K x 16)
[5]
[5]
