Rainbow Electronics DS1511 User Manual

WE

KS

CE

A

A3A

A

A

PWR

R

IRQ

Y2K Watchdog Real-Time Clocks

www.maxim-ic.com

GENERAL DESCRIPTION

The DS1501/DS1511 are full-function, year 2000­compliant real-time clock/calendars (RTCs) with an
RTC alarm, watchdog timer, power-on reset, battery
monitors, 256 bytes NV SRAM, and a 32.768kHz
output. User access to all registers within the
DS1501/DS1511 is accomplished with a byte-wide
interface, as shown in Figure 8. The RTC registers
contain century, year, month, date, day, hours,
minutes, and seconds data in 24-hour binary-coded
decimal (BCD) format. Corrections for day of month
and leap year are made automatically.

APPLICATIONS

Remote Systems
Battery-Backed Systems
Telecom Switches
Office Equipment
Consumer Electronics

ORDERING INFORMATION

PART TEMP RANGE PIN-PACKAGE

DS1501YN

DS1501YEN -40°C to +85°C 28 TSOP

DS1501YSN -40°C to +85°C 28 SO (330 mil)

DS1501WN -40°C to +85°C 28 DIP (600 mil)

DS1501WEN -40°C to +85°C 28 TSOP

DS1501WSN -40°C to +85°C 28 SO (330 mil)

DS1511Y

DS1511W 0°C to +70°C 28 720-mil Module

Selector Guide appears at end of data sheet.

Typical Operating Circuits appears at end of data sheet.

-40°C to +85°C 28 DIP (600 mil)

0°C to +70°C 28 720-mil Module

FEATURES

§ BCD-Coded Century, Year, Month, Date, Day,
Hours, Minutes, and Seconds with Automatic
Leap-Year Compensation Valid Up to the Year
2100

§ Programmable Watchdog Timer and RTC Alarm

§ Century Register; Y2K-Compliant RTC

§ Automatic Battery Backup and Write Protection

to External SRAM

§ +3.3 or +5V Operation

§ Precision Power-On Reset

§ Power-Control Circuitry Support System Power-

On from Date/Day/Time Alarm or Key
Closure/Modem-Detect Signal

§ 256 Bytes Battery-Backed NV SRAM

§ Auxiliary Battery Input

§ Accuracy of DS1511 Better than ±1

Minute/Month at +25°C

§ Day-of-Week/Date Alarm Register

§ Crystal Select Bit Allow RTC to Operate with 6pF

or 12.6pF Crystal

§ Battery Voltage-Level Indicator Flags

§ Available as Chip (DS1501) or Standalone

Module with Embedded Battery and Crystal
(DS1511)

§ UL Recognized

PIN CONFIGURATION

TOP VIEW

X1
X2

ST

4

2
1

0
DQ0
DQ1
DQ2

GND

DS1501/DS1511

1
2
3
4

Dallas

5

Semiconductor

DS1501

6
7
8
9
10
11
12
13
14

28

V
27
26
25
24
23
22
21
20
19
18
17
16
15

CC

V

BAUX

V

BAT

SQW

OE

GND

DQ7

DQ6

DQ5

DQ4

DQ3

DIP, SO

Pin Configurations are 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.maxim-ic.com/errata

.

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REV: 030603

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 (Module) 0°C to +70°C
Operating Temperature Range, DS1501

-40°C to +85°C (Note 1)

Operating Temperature Range, DS1511 0°C to +70°C
Storage Temperature Range, DS1501

-55°C to +125°C

Storage Temperature Range, DS1511 -40°C to +70°C
Soldering Temperature (DIP, Module) +260°C Lead Temperature for 10 seconds (max) (Note 2)
Soldering Temperature (SO, TSOP)

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.

See IPC/JEDEC J-STD-020A for Surface Mount Devices

RECOMMENDED DC OPERATING CONDITIONS

(VCC = 3.3V or 5V ±10%, TA = 0°C to +70°C; VCC = 3.3V or 5V ±10%, TA = -40°C to +85°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Power Supply Voltage (Note 3) VCC

Logic 1 Voltage All Inputs (Note 3) VIH
Pullup Voltage, IRQ, PWR, and

RST Outputs (Note 3)

V

PU

Logic 0 Voltage All Inputs (Note 3) VIL

Battery Voltage (Note 3) V

Auxiliary Battery Voltage (Note 3) V

BAT

BAUX

5V (Y) 4.5 5.0 5.5

3.3V (W) 3.0 3.3 3.6
Y 2.2 VCC + 0.3
W 2.0 V

+ 0.3

CC

V

V

5.5 V

Y -0.3 +0.8
W -0.3 +0.6

V

2.5 3.0 3.7 V

Y 2.5 3.0 5.3
W 2.5 3.0 3.7

V

DC ELECTRICAL CHARACTERISTICS

(VCC = 3.3V or 5V ±10%, TA = 0°C to +70°C; VCC = 3.3V or 5V ±10%, TA = -40°C to +85°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Active Supply Current (Note 4) ICC

I

(

CE = V

)

IH

CMOS Standby Current
(

CE = V

- 0.2V)

CC

CC1

I

CC2

Input Leakage Current (Any Input) IIL -1 +1

Output Leakage Current
(Any Output)
Output Logic 1 Voltage

= -1.0mA)

(I

OUT

Output Logic 0 Voltage (I

2.1mA, DQ0–7; I
I

= 7.0mA, PWR and RST )

OUT

= 5.0mA, IRQ,

OUT

(Note 2)

OUT

=

I

OL

V

OH

V

OL1

V

OL2

V

BLF

Power-Fail Voltage (Note 2) VPF

Battery Switchover Voltage
(Notes 3, 6)

V

SO

Y 15
W 10
Y 5 TTL Standby Current
W 4
Y 5
W 4

mA

mA

mA

mA

-1 +1

mA

(Note 3) 2.4 V

(Note 3) 0.4 V

(Notes 3, 5) 0.4 V

Y 2.0 Battery Low, Flag Trip Point
W 1.9
Y 4.20 4.50
W 2.75 2.97

V

BAT,

V

BAUX,

or V

PF

V

V

V

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DS1501/DS1511 Y2KC Watchdog Real-Time Clocks

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Battery Leakage Current I

100 nA

LKG

DC ELECTRICAL CHARACTERISTICS

(VCC = 0V; TA = 0°C to +70°C; VCC = 0V, TA = -40°C to +85°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Battery Current, BB32 = 0, EOSC = 0
Battery Current, BB32 = 0, EOSC = 1
V

Current BB32 = 1, SQW Open I

BAUX

BAT1

I

BAT2

BAUX

(Note 7)
(Note 7)

(Note 7) 2 µA

0.27 1.0 µA

0.01 0.1 µA

I

CRYSTAL SPECIFICATIONS*

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Nominal Frequency fO 32.768 kHz
Series Resistance ESR 45 kΩ
Load Capacitance CL 6 pF

*The crystal, traces, and crystal input pins should be isolated from RF generating signals. Refer to Application Note 58: Crystal Considerations
for Dallas Real-Time Clocks for additional specifications.

AC OPERATING CHARACTERISTICS

(VCC = 5V ±10%, TA = 0°C to +70°C; VCC = 5V ±10%, TA = -40°C to +85°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Read Cycle Time tRC
Address Access Time tAA

CE to DQ Low-Z
CE Access Time
CE Data Off Time
OE to DQ Low-Z (0°C to +85°C)
OE to DQ Low-Z (-40°C to 0°C)
OE Access Time
OE Data Off Time

Output Hold from Address tOH
Write Cycle Time
Address Setup Time

WE Pulse Width
CE Pulse Width

Data Setup Time
Data Hold Time
Address Hold Time

WE Data Off Time

Write Recovery Time
Pulse Width, OE, WE, or CE High
Pulse Width, OE, WE, or CE Low

PW
PW

t
t
t
t
t
t
t

CEL

CEA

CEZ

OEL

OEL

OEA

OEZ

(Note 8)

(Note 8)
(Note 8)
(Note 8)

(Note 8)

70 ns

t

WC

0 ns

t

AS

t

50 ns

WEW

t

55 ns

CEW

30 ns

t

DS

t

5 ns

DH

0 ns

t

AH

t

(Note 8) 25 ns

WEZ

t

15 ns

WR

20 ns

HIGH

70 ns

LOW

70 ns

70 ns

5 ns

70 ns

25 ns
5 ns
2 ns

35 ns

25 ns
5 ns

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DS1501/DS1511 Y2KC Watchdog Real-Time Clocks

OE C

AC OPERATING CHARACTERISTICS

(VCC = 3.3V ±10%, TA = 0°C to +70°C; VCC = 3.3V ±10%, TA = -40°C to +85°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Read Cycle Time
Address Access Time

CE to DQ Low-Z
CE Access Time
CE Data Off Time
OE to DQ Low-Z (0°C to +85°C)
OE to DQ Low-Z (-40°C to 0°C)
OE Access Time
OE Data Off Time

Output Hold from Address
Write Cycle Time
Address Setup Time

WE Pulse Width
CE Pulse Width

Data Setup Time
Data Hold Time
Address Hold Time

WE Data Off Time

Write Recovery Time
Pulse Width, OE, WE, or CE High
Pulse Width, OE, WE, or CE Low

Figure 1. Read Cycle Timing

120 ns

t

RC

120 ns

t

AA

t

(Note 8) 5 ns

CEL

t

120 ns

CEA

t

(Note 8) 40 ns

CEZ

t

(Note 8) 5 ns

OEL

t

(Note 8) 2 ns

OEL

t

100 ns

OEA

t

(Note 8) 35 ns

OEZ

5 ns

t

OH

120 ns

t

WC

0 ns

t

AS

t

100 ns

WEW

t

110 ns

CEW

80 ns

t

DS

5 ns

t

DH

5 ns

t

AH

t

(Note 8) 40 ns

WEZ

15 ns

t

WR

PW
PW

40 ns

HIGH

100 ns

LOW

t

RC

A0–A4

E

DQ0-DQ7

t

t

AA

t

CEA

t

CEL

t

OEA

t

OEL

VALID

t

OEZ

OH

t

CEZ

4 of 20

DS1501/DS1511 Y2KC Watchdog Real-Time Clocks

WE C

WE C

Figure 2. Write Cycle Timing, Write-Enable-Controlled

t

WC

A0–A4

VALID VALID

t

AS

t

AH

E

t

AS

t

WEW

DQ0–DQ7

DATA OUTPUT DATA INPUT

t

WEZ

t

DS

DATA INPUT

t

DH

Figure 3. Write Cycle Timing, Chip-Enable-Controlled

t

WR

A0–A4

E

DQ0–DQ7

t

WC

VALID VALID

t

AS

t

AS

t

CEW

t

DS

DATA INPUT

t

AH

t

WR

t

DH

DATA INPUT

5 of 20

Figure 4. Burst Mode Timing Waveform

O

DS1501/DS1511 Y2KC Watchdog Real-Time Clocks

A0–A4

E, WE, OR CE

DQ0–DQ7

13h

LOW

PW

HIGH

PW

POWER-UP/DOWN CHARACTERISTICS

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CE or WE at V

IH

VCC Fall Time: V

VCC Fall Time: V

VCC Rise Time: V

VPF to RST High

t

t

REC

PF

FB

F

R

Before Power-Fail

to V

PF(MAX)

to VSO t

PF(MIN)

to V

PF(MIN)

t

PF(MIN)

t

PF(MAX)

0

300

10

0

ms

ms

ms

ms

35 200 ms

(TA = +25°C)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Expected Data Retention Time
(Oscillator On)

t

(Note 9) 10 years

DR

CAPACITANCE

(TA = +25°C)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Capacitance on All Input Pins CIN 10 pF
Capacitance on IRQ, PWR, RST, and DQ

Pins

10 pF

C

IO

AC TEST CONDITIONS

OUTPUT LOAD

(Y) 50pF + 1TTL Gate Input: 1.5V

(W) 25pF + 1 TTL Gate

INPUT PULSE

LEVELS

0V to 3.0V for 5V

operation

TIMING MEASUREMENT

REFERENCE LEVELS

Output: 1.5V

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INPUT PULSE RISE

AND FALL TIMES

5ns