DS1643 Datasheet, PDF (2/17 Pages) Dallas Semiconductor – Nonvolatile Timekeeping RAM

DS1643/DS1643P
PIN DESCRIPTION
PIN
PDIP PowerCap
NAME
1
1, 2, 3,
31–34
N.C.
2
30
A12
3
25
A7
4
24
A6
5
23
A5
6
22
A4
7
21
A3
8
20
A2
9
19
A1
10
18
A0
21
28
A10
23
29
A11
24
27
A9
25
26
A8
11
16
DQ0
12
15
DQ1
13
14
DQ2
15
13
DQ3
16
12
DQ4
17
11
DQ5
18
10
DQ6
19
9
DQ7
20
8
CE
22
7
OE
26
—
CE2
27
6
WE
28
5
V_CC
—
4
PFO
14
17
GND
—
X1, X2,
V_BAT
No Connection
FUNCTION
Address Inputs
Data Input/Output
Active-Low Chip-Enable Input
Active-Low Output-Enable Input
Chip-Enable 2 Input (Active High)
Active-Low Write-Enable Input
Power-Supply Input
Active-Low Power-Fail Output. This open-drain pin requires a
pullup resistor for proper operation.
Ground
Crystal Connection, Battery Connection
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