X1227
Write Cycle Timing
SCL
SDA
8th Bit of Last Byte
ACK
t
WC
Stop
Start
Condition
Condition
Power Up Timing
Symbol
Parameter
Min.
Typ.(2)
Max.
Units
ms
(1)
t
Time from Power Up to Read
Time from Power Up to Write
1
5
PUR
(1)
t
ms
PUW
Notes: (1) Delays are measured from the time V
is stable until the specified operation can be initiated. These parameters are not 100%
CC
tested.V slew rate should be between 0.2mV/µsec and 50mV/µsec.
CC
(2) Typical values are for T = 25°C and V = 5.0V
A
CC
Nonvolatile Write Cycle Timing
Symbol
Parameter
Min.
Typ.(1)
Max.
Units
(1)
t
Write Cycle Time
5
10
ms
WC
Note: (1) t
is the time from a valid stop condition at the end of a write sequence to the end of the self-timed internal nonvolatile write cycle.
WC
It is the minimum cycle time to be allowed for any nonvolatile write by the user, unless Acknowledge Polling is used.
WATCHDOG TIMER/LOW VOLTAGE RESET OPERATING CHARACTERISTICS
Watchdog/Low Voltage Reset Parameters (See Figures ± and 4)
Symbols
Parameters
Min.
Typ.
Max.
Unit
Programmed Reset Trip Voltage
X1227-4.5A
X1227
X1227-2.7A
X1227-2.7
4.50
4.25
2.75
2.55
4.63
4.38
2.85
2.65
4.75
4.50
2.95
2.75
V
V
PTRIP
t
V
Detect to RESET LOW
500
400
ns
RPD
CC
Power Up Reset Time-out Delay
t
100
250
ms
PURST
t
V
V
Fall Time
Rise Time
10
10
µs
µs
F
CC
t
R
CC
Watchdog Timer Period (Crystal=32.768kHz):
WD1=0, WD0=0
1.7
725
225
1.75
750
250
1.8
775
275
s
ms
ms
t
WDO
WD1=0, WD0=1
WD1=1, WD0=0
t
Watchdog Reset Time-out Delay (Crystal=32.768kHz)
2-Wire interface
225
1
250
275
ms
µs
V
RST
t
RSP
V
Reset Valid V
1.0
RVALID
CC
Characteristics subject to change without notice. 19 of 28
REV 1.1.20 1/13/03
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XICOR [ XICOR INC. ]
