DS1558 Datasheet, PDF (1/18 Pages) Dallas Semiconductor – Watchdog Clock with NV RAM Control

DS1558
Watchdog Clock with NV RAM Control
www.maxim-ic.com
FEATURES
§ Integrated Real-Time Clock (RTC), Power-
Fail Control Circuit, and NV RAM Controller
§ Clock Registers are Accessed Identically to
the Static RAM; These Registers are Resident
in the 16 Top RAM Locations
§ Century Register
§ Greater than 10 Years of Timekeeping and
Data Retention in the Absence of Power with
Small Lithium Coin Cell(s) and Low-Leakage
SRAM
§ Precision Power-On Reset
§ Programmable Watchdog Timer and RTC
Alarm
§ BCD-Coded Year, Month, Date, Day, Hours,
Minutes, and Seconds with Automatic Leap-
Year Compensation Valid Up to the Year
2100
§ Battery Voltage-Level Indicator Flag
§ Power-Fail Write Protection Allows for ±10%
V_CC Power-Supply Tolerance
§ Underwriters Laboratory (UL) Recognized
PIN CONFIGURATION
TOP VIEW
N.C.
1
A18
2
A16
3
A14
4
A12
5
A7
6
A6
7
A5
8
A4
9
A3
10
A2
11
A1
12
DS1558
36
A15
35
VBAT1
34
WE
33
IRQ/FT
32
A13
31
A8
30
A9
29
A11
28
OE
27
A10
26
CE
25
OER
TQFP
For package information, go to :
www.maxim-ic.com/DallasPackInfo
ORDERING INFORMATION
PART
TEMP RANGE
DS1558W
DS1558W+
DS1558W-TRL
DS1558W+TRL
DS1558Y
DS1558Y+
DS1558Y-TRL
DS1558Y+TRL
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
VOLTAGE
(V)
3.3
3.3
3.3
3.3
5.0
5.0
5.0
5.0
+ Denotes a lead-free/RoHS-compliant device.
* A “+” anywhere on the top mark indicates a lead-free device.
PIN-PACKAGE
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
48 TQFP (7 x 7 x 1mm)
TOP MARK*
DS1558D
DS1558D
DS1558D
DS1558D
DS1558B
DS1558B
DS1558B
DS1558B
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata..
1 of 18
REV: 071305