DS17285 Datasheet, PDF (14/38 Pages) Dallas Semiconductor – 3V/5V Real-Time Clock

DS17285/DS17287
Table 2. PERIODIC INTERRUPT RATE AND SQUARE-WAVE OUTPUT
FREQUENCY
EXTENDED
REGISTER B
E32k
SELECT BITS REGISTER A
RS3
RS2
RS1
RS0
t_PI PERIODIC
INTERRUPT RATE
SQW OUTPUT
FREQUENCY
0
0
0
0
0
None
None
0
0
0
0
1
3.90625ms
256Hz
0
0
0
1
0
7.8125ms
128Hz
0
0
0
1
1
122.070µs
8.192kHz
0
0
1
0
0
244.141µs
4.096kHz
0
0
1
0
1
488.281µs
2.048kHz
0
0
1
1
0
976.5625µs
1.024kHz
0
0
1
1
1
1.953125ms
512Hz
0
1
0
0
0
3.90625ms
256Hz
0
1
0
0
1
7.8125ms
128Hz
0
1
0
1
0
15.625ms
64Hz
0
1
0
1
1
31.25ms
32Hz
0
1
1
0
0
62.5ms
16Hz
0
1
1
0
1
125ms
8Hz
0
1
1
1
0
250ms
4Hz
0
1
1
1
1
500ms
2Hz
1
X
X
X
X
*
32.768kHz
*RS3 to RS0 determine periodic interrupt rates as listed for E32k = 0.
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