
DS1390–DS1394
Low-Voltage SPI/3-Wire RTCs with
Trickle Charger
10
Maxim Integrated
Typical Operating Characteristics
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
IBACKUP vs. VBACKUP, BBSQ1 = 0
DS1390
TOC01
VBACKUP (V)
SUPPLY
CURRENT
(nA)
4.5 4.9
4.1
3.3 3.7
2.9
2.5
2.1
1.7
350
400
450
500
550
600
300
1.3
5.3
VCC= 0
IBACKUP vs. VBACKUP, BBSQ1 = 1
DS1390
toc02
VBACKUP (V)
SUPPLY
CURRENT
(nA)
5.3
4.9
4.1 4.5
2.1 2.5 2.9 3.3 3.7
1.7
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
300
1.3
VCC = 0V
IBACKUP vs. TEMPERATURE
VBACKUP = 3.0V
DS1390
toc03
TEMPERATURE (
°C)
SUPPLY
CURRENT
(nA)
80
60
40
20
0
-20
300
400
350
450
500
550
600
250
-40
VCC = 0V
OSCILLATOR FREQUENCY
vs. SUPPLY VOLTAGE
DS1390
toc04
SUPPLY (V)
FREQUENCY
(Hz)
5.3
4.8
4.3
3.8
3.3
2.8
2.3
1.8
32767.85
32767.90
32767.95
32768.00
32767.80
1.3