BQ4285E Datasheet, PDF (18/32 Pages) Texas Instruments – Enhanced RTC With NVRAM Control

bq4285E/L
Read/Write Timing—bq4285E (TA = TOPR, VCC = 5V ± 10%)
Symbol
Parameter
tCYC
Cycle time
tDSL
DS low or RD/WR high time
tDSH
DS high or RD/WR low time
tRWH
R/W hold time
tRWS
R/W setup time
tCS
Chip select setup time
tCH
Chip select hold time
tDHR
Read data hold time
tDHW
Write data hold time
tAS
Address setup time
tAH
Address hold time
tDAS
Delay time, DS to AS rise
tASW
Pulse width, AS high
tASD
Delay time, AS to DS rise
(RD/WR fall)
tOD
Output data delay time from DS
rise (RD fall)
tDW
Write data setup time
tBUC
Delay time before update
tPI
Periodic interrupt time interval
tUC
Time of update cycle
Minimum
160
80
55
0
10
5
0
0
0
20
5
10
30
35
-
30
-
-
-
Typical
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
244
-
1
Maximum
-
-
-
-
-
-
-
25
-
-
-
-
-
-
50
-
-
-
-
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
µs
-
µs
Notes
See Table 3
18