CY7C148 Cypress Semiconductor, CY7C148 Datasheet - Page 3

• Manufacturer Part Number: CY7C148
• Description: (CY7C148 / CY7C149) 1K x 4 Static RAM
• Manufacturer: Cypress Semiconductor

AC Test Loads and Waveforms
Switching Characteristics
OUTPUT
Equivalent to:
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
Notes:
RC
AA
ACS1
ACS2
ACS
LZ
HZ
OH
PD
PU
WC
WP
WR
WZ
DW
DH
AS
CW
OW
AW
6.
7.
8.
9.
READ CYCLE
WRITE CYCLE
Parameter
[8]
[8]
[9]
[8]
[9]
[8]
INCLUDING
Chip deselected greater than 25 ns prior to selection.
Chip deselected less than 25 ns prior to selection.
At any given temperature and voltage condition, t
loading in part (b) of AC Test Loads.
The internal write time of the memory is defined by the overlap of CS LOW and WE LOW. Both signals must be LOW to initiate a write and either signal can
terminate a write by going high. The data input set-up and hold timing should be referenced to the rising edge of the signal that terminates the write.
5V
JIG AND
SCOPE
30 pF
OUTPUT
Address Valid to Address Do Not Care Time
(Read Cycle Time)
Address Valid to Data Out Valid Delay
(Address Access Time)
Chip Select LOW to Data Out Valid (7C148 only)
Chip Select LOW to Data Out Valid (7C149 only)
Chip Select LOW to Data Out On
Chip Select HIGH to Data Out Off
Address Unknown to Data Out Unknown Time
Chip Select HIGH to Power-Down Delay
Chip Select LOW to Power-Up Delay
Address Valid to Address Do Not Care
(Write Cycle Time)
Write Enable LOW to Write Enable HIGH
Address Hold from Write End
Write Enable to Output in High Z
Data in Valid to Write Enable HIGH
Data Hold Time
Address Valid to Write Enable LOW
Chip Select LOW to Write Enable HIGH
Write Enable HIGH to Output in Low Z
Address Valid to End of Write
THÉ VENIN EQUIVALENT
R1481
(a)
R2
255
167
OUTPUT
Over the Operating Range
Description
INCLUDING
5V
JIG AND
SCOPE
HZ
5 pF
1.73V
is less than t
R1481
(b)
LZ
for all devices. Transition is measured 500 mV from steady-state voltage with specified
7C148
7C149
7C148
7C148
R2
255
C148–4
[2]
3
Min.
25
25
20
12
20
20
7C148 25
7C149 25
8
5
0
0
0
5
0
0
0
0
3.0V
GND
Max.
25
30
25
15
15
20
8
[6]
[7]
< 10 ns
Min.
35
10
35
30
20
30
30
7C148 35
7C149 35
5
0
0
0
5
0
0
0
0
10%
ALL INPUT PULSES
Max.
90%
35
35
35
15
20
30
8
Min.
45
10
45
35
20
40
35
7C148 45
7C149 45
5
0
5
0
5
0
0
0
0
Max.
CY7C148
CY7C149
45
45
45
20
20
30
90%
8
10%
< 10 ns
C148–5
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns