DS1501/DS1511
Y2K-Compliant Watchdog
Real-Time Clocks
GENERAL DESCRIPTION FEATURES
BCD-Coded Century, Year, Month, Date, Day,
The DS1501/DS1511 are f-ulfuncl tion, year 2000-
Hours, Minutes, and Seconds with Automatic
compliant real-time clock/calendars (RTCs) with an
Leap-Year Compensation Valid Up to the Year
RTC alarm, watchdog timer, poweron - reset, battery
2100
monitors, 256 bytes NV SRAM, and a 32.768kHz
output. User access to all registers within the Programmable Watchdog Timer and RTC
DS1501/DS1511 is accomplished with a bywteide -
Alarm
interface, as shown in Figure 8. The RTC registers
Century Register; Y2K-Compliant RTC
contain century, year, month, date, day, hours,
+3.3 (W) or +5V (Y) Operation
minutes, and seconds data in 24h-our binary-coded
Precision Power-On Reset
decimal (BCD) format. Corrections for day of month
and leap year are made automatically. Power-Control Circuitry Support System
Power-On from Date/Day/Time Alarm or Key
Closure/Modem-Detect Signal
APPLICATIONS
256 Bytes Battery-Backed SRAM
Remote Systems
Auxiliary Battery Input
Battery-Backed Systems
Telecom Switches
Accuracy of DS1511 Better than 1
Office Equipment Minute/Month at +25C
Consumer Electronics
Day-of-Week/Date Alarm Register
Crystal Select Bit Allow RTC to Operate with
6pF or 12.6pF Crystal (DS1501)
Battery Voltage-Level Indicator Flags
Pin Configurations and Typical Operating Circuit appear at
Available as Chip (DS1501) or Stand-Alone
end of data sheet.
Encapsulated DIP Module with Embedded
Battery and Crystal (DS1511)
Underwriters Laboratories (UL) Recognized
ORDERING INFORMATION
PART VOLTAGE (V) TEMP RANGE PIN-PACKAGE TOP MARK*
DS1501WE+ 3.3 28 TSOP DS1501WE
0 C to +70 C
DS1501WEN+ 3.3 28 TSOP
-40 C to +85C DS1501WEN
DS1501WEN+T&R 3.3 28 TSOP DS1501WEN
-40 C to +85C
DS1501WE+T&R 3.3 28 TSOP
0 C to +70 C DS1501WE
+Denotes a lead(Pb)-free/RoHS-compliant package.
*A + anywhere on the top mark denotes a lead(Pb)-free device. An N or IND denotes an industrial temperature device.
T&R = Tape and reel.
Ordering Information continued at end of data sheet.
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.maximintegrated.com/errata.
1 of 22 19-6820; Rev 10/13 DS1501/DS1511 Y2KC Watchdog Real-Time Clocks
ABSOLUTE MAXIMUM RATINGS
Voltage Range on Any Pin Relative to Ground.......-0.5V to +6.0V
Operating Temperature Range
DS1501..-40C to +85C (Note 1)
DS1511....0C to +70C
Storage Temperature Range
DS1501......-55C to +125C
DS1511.....-40C to +70C
Lead Temperature (soldering, 10 seconds)............+260C
Note: EDIP is hand or wave-soldered only. (Note 2)
Soldering Temperature (reflow, SO or TSOP).........................................................................+260C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is
not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED DC OPERATING CONDITIONS
(DS1511: V = 3.3V or 5V 10%, T = 0C to +70C; DS1501: V = 3.3V or 5V 10%, T = -40C to +85C.)
CC A CC A
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
5V (Y) 4.5 5.0 5.5
Power Supply Voltage (Note 3) V V
CC
3.3V (W) 3.0 3.3 3.6
Y 2.2 V + 0.3
CC
Logic 1 Voltage All Inputs (Note 3) V V
IH
W 2.0 V + 0.3
CC
Pullup Voltage, IRQ, PWR, and
V 5.5 V
PU
RST Outputs (Note 3)
Y -0.3 +0.8
Logic 0 Voltage All Inputs (Note 3) V V
IL
W -0.3 +0.6
Battery Voltage (Note 3) V 2.5 3.0 3.7 V
BAT
Y 2.5 3.0 5.3
Auxiliary Battery Voltage (Note 3) V V
BAUX
W 2.5 3.0 3.7
DC ELECTRICAL CHARACTERISTICS
(DS1511: V = 3.3V or 5V 10%, T = 0C to +70C; DS1501: V = 3.3V or 5V 10%, T = -40C to +85C.)
CC A CC A
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Y 15
Active Supply Current (Note 4) I mA
CC
W 10
Y 5
TTL Standby Current (CE = V ) I mA
IH CC1
W 4
CMOS Standby Current Y 5
I mA
CC2
(CE = V - 0.2V)
W 4
CC
Input Leakage Current (Any Input) I -1 +1
A
IL
Output Leakage Current (Any Output) I -1 +1 A
OL
Output Logic 1 Voltage
V (Note 3) 2.4 V
OH
(I = -1.0mA)
OUT
Output Logic 0 Voltage (I = 2.1mA,
OUT V (Note 3) 0.4 V
OL1
DQ07; I = 5.0mA, IRQ, I =
OUT OUT
V (Notes 3, 5) 0.4 V
OL2
7.0mA, PWR and RST)
Y 2.0
Battery Low, Flag Trip Point (Note 2) V V
BLF
W 1.9
Y 4.20 4.50
Power-Fail Voltage (Note 2) V V
PF
W 2.75 2.97
2 of 22