DS1302 Trickle-Charge Timekeeping Chip
Table 3. Register Address/Definition
RTC
READ
81h
83h
85h
87h
89h
8Bh
8Dh
8Fh
91h
WRITE
80h
82h
84h
86h
88h
8Ah
8Ch
8Eh
90h
BIT 7
CH
12/
24
0
0
0
WP
TCS
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RANGE
00–59
00–59
1–12/0–23
1–31
1–12
1–7
00–99
—
—
10 Seconds
10 Minutes
10
0
Hour
AM
/PM
0
10 Date
10
0
0
Month
0
0
0
10 Year
0
0
0
TCS
TCS
TCS
Seconds
Minutes
Hour
Date
Month
0
0
DS
Day
Year
0
0
DS
RS
0
RS
CLOCK BURST
BFh
BEh
RAM
C1h
C3h
C5h
.
.
.
FDh
C0h
C2h
C4h
.
.
.
FCh
00-FFh
00-FFh
00-FFh
.
.
.
00-FFh
RAM BURST
FFh
FEh
Figure 5. Programmable Trickle Charger
TRICKLE CHARGE REGISTER (90h write, 91h read)
Bit 7
TCS3
Bit 6
TCS2
Bit 5
TCS1
Bit 4
TCS0
Bit 3
DS1
Bit 2
DS0
Bit 1
ROUT1
Bit 0
ROUT0
TCS
0-3
= TRICKLE CHARGER SELECT
DS
0-1
= DIODE SELECT
ROUT
0-1
= RESISTOR SELECT
1 0F 16 SELECT
NOTE: ONLY 1010b ENABLES CHARGER
1 OF 2
SELECT
1 OF 3
SELECT
R1
V
CC2
2K
Ω
R2
4k
Ω
R3
8k
Ω
V
CC1
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