DS1646 View Datasheet(PDF) - Dallas Semiconductor -> Maxim Integrated
Part Name
Description
Manufacturer
DS1646 Datasheet PDF : 12 Pages
| |||
DS1646/DS1646P
DS1646/DS1646P
Nonvolatile Timekeeping RAM
FEATURES
• Integrated NV SRAM, real time clock, crystal, power–
fail control circuit and lithium energy source
• Clock registers are accessed identical to the static
RAM. These registers are resident in the eight top
RAM locations.
• Totally nonvolatile with over 10 years of operation in
the absence of power
• Access times of 120 ns and 150 ns
• BCD coded year, month, date, day, hours, minutes,
and seconds with leap year compensation valid up to
2100
• Power–fail write protection allows for ±10% VCC pow-
er supply tolerance
• DS1646 only (DIP Module)
– Standard JEDEC Byte–wide 128K x 8 RAM pin-
out
• DS1646P only (PowerCap Module Board)
– Surface mountable package for direct connec-
tion to PowerCap containing battery and crystal
– Replaceable battery (PowerCap)
– Power–fail output
– Pin–for–pin compatible with other densities of
DS164XP Timekeeping RAM
ORDERING INFORMATION
DS1646–XXX 32–pin DIP module
–120 120 ns access
–150 150 ns access
*DS1646P–XXX 34–pin PowerCap Module Board
–120 120 ns access
–150 150 ns access
*DS9034PCX (PowerCap) Required;
must be ordered separately
PIN ASSIGNMENT
NC 1
A16 2
A14 3
A12 4
A7 5
A6 6
A5 7
A4 8
A3 9
A2 10
A1 11
A0 12
DQ0 13
DQ1 14
DQ2 15
GND 16
32 VCC
31 A15
30 NC
29 WE
28 A13
27 A8
26 A9
25 A11
24 OE
23 A10
22 CE
21 DQ7
20 DQ6
19 DQ5
18 DQ4
17 DQ3
32–PIN ENCAPSULATED PACKAGE
NC
1
34
NC
A15
2
33
NC
A16
3
32
A14
PFO
4
31
A13
VCC
5
WE
6
30
A12
29
A11
OE
7
28
A10
CE
8
27
A9
DQ7
9
26
A8
DQ6
10
25
A7
DQ5
11
24
A6
DQ4
12
23
A5
DQ3
13
22
A4
DQ2
14
21
A3
DQ1
15 X1 GND VBAT X2 20
A2
DQ0
16
19
A1
GND
17
18
A0
34–PIN POWERCAP MODULE BOARD
(USES DS9034PCX POWERCAP)
PIN DESCRIPTION
A0–A16
CE
OE
WE
VCC
GND
DQ0–DQ7
NC
PFO
X1, X2
VBAT
– Address Input
– Chip Enable
– Output Enable
– Write Enable
– +5 Volts
– Ground
– Data Input/Output
– No Connect
– Power–Fail Output (DS1646P only)
– Crystal Connection
– Battery Connection
031698 1/12
Share Link: 