Low-Voltage SPI/3-Wire RTCs with
Trickle Charger
DS1390/DS1391/DS1392/DS1393
Typical Operating Characteristics
(V
CC
= +3.3V, T
A
= +25擄C, unless otherwise noted.)
I
BACKUP
vs. V
BACKUP
, BBSQ1 = 0
V
CC
= 0
550
SUPPLY CURRENT (nA)
500
450
400
350
300
1.3 1.7 2.1 2.5 2.9 3.3 3.7 4.1 4.5 4.9 5.3
V
BACKUP
(V)
DS1390 TOC01
I
BACKUP
vs. V
BACKUP
, BBSQ1 = 1
1000
950
900
850
800
750
700
650
600
550
500
450
400
350
300
V
BACKUP
(V)
V
CC
= 0V
DS1390 toc02
600
SUPPLY CURRENT (nA)
1.3 1.7 2.1 2.5 2.9 3.3 3.7 4.1 4.5 4.9 5.3
I
BACKUP
vs. TEMPERATURE
V
BACKUP
= 3.0V
DS1390 toc03
OSCILLATOR FREQUENCY
vs. SUPPLY VOLTAGE
DS1390 toc04
600
V
CC
= 0V
550
SUPPLY CURRENT (nA)
500
450
400
350
300
250
-40
-20
0
20
40
60
80
TEMPERATURE (擄C)
32768.00
32767.95
FREQUENCY (Hz)
32767.90
32767.85
32767.80
1.3
1.8
2.3
2.8
3.3 3.8
4.3
4.8
5.3
SUPPLY (V)
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