fm3808 Ramtron Corporation, fm3808 Datasheet - Page 20

• Manufacturer Part Number: fm3808
• Description: 256kb Bytewide Fram W/ Real-time Clock
• Manufacturer: Ramtron Corporation

Read Cycle AC Parameters (T
Write Cycle AC Parameters (T
Notes
1
2
Power Cycle Timing (T
Notes
1
2
3
4
5
Rev. 1.3 (EOL)
Feb. 2006
Symbol
t
t
t
t
t
t
t
t
t
Symbol
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
CE
CA
RC
PC
AS
AH
OE
HZ
OHZ
CA
CW
WC
PC
AS
AH
WP
DS
DH
WZ
WX
HZ
WS
WH
INT
PD
RI
R
F
Symbol
This parameter is periodically sampled and not 100% tested.
The relationship between /CE and /WE determines if a /CE- or /WE-controlled write occurs. There is no timing
specification associated with this relationship.
This parameter is periodically sampled and not 100% tested.
If power monitor is programmed to generate INT.
Access is blocked at V
may be useful in accomplishing this.
Failing to satisfy t
result in improper operation.
Slew rate for proper transition between the locked-out condition and normal operation.
Parameter
Chip Enable Access Time ( to data valid)
Chip Enable Active Time
Read Cycle Time
Precharge Time
Address Setup Time
Address Hold Time
Output Enable Access Time
Chip Enable to Output High-Z
Output Enable to Output High-Z
Parameter
Chip Enable Active Time
Chip Enable to Write High
Write Cycle Time
Precharge Time
Address Setup Time
Address Hold Time
Write Enable Pulse Width
Data Setup
Data Hold
Write Enable Low to Output High Z
Write Enable High to Output Driven
Chip Enable to Output High-Z
Write Setup
Write Hold
INT signal active after V
Last Access Complete to V
VLO to inputs recognized on power-up
Rise time of V
Fall time of V
RI
may result in the first access being ignored. Failure to raise /CE to a logic high prior to V
A
LO
= -40 C to + 85 C)
. The last access should be complete prior to reaching V
DD
DD
A
A
from V
= -40 C to + 85 C, V
from V
= -40 C to + 85 C, V
Parameter
LO
BG
TP
to V
LO
to V
BG
LO
DD
DD
= 4.5V to 5.5V unless otherwise specified)
= 4.5V to 5.5V unless otherwise specified)
Min
Min
Min
130
100
100
130
70
70
60
10
30
30
10
70
60
10
0
5
0
0
0
1
0
LO
. The early warning power fail interrupt
2,000
2,000
Max
Max
Max
100
15
15
70
10
15
15
Units
Units
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
s
s
s
DD
Page 20 of 27
Notes
Notes
>V
Notes
FM3808
1,2
1,3
1,4
1,5
1,5
1
1
1
1
1
2
2
LO
may