DS1340U-3+T&R; datasheet, PDF - EEWORLD Datasheet

DS1340

I

2

C RTC with Trickle Charger

General Description

The DS1340 is a real-time clock (RTC)/calendar that is

pin compatible and functionally equivalent to the ST

M41T00, including the software clock calibration. The

device additionally provides trickle-charge capability

on the V

BACKUP

pin, a lower timekeeping voltage, and

an oscillator STOP flag. Block access of the register

map is identical to the ST device. Two additional regis-

ters, which are accessed individually, are required for

the trickle charger and flag. The clock/calendar pro-

vides seconds, minutes, hours, day, date, month, and

year information. A built-in power-sense circuit detects

power failures and automatically switches to the back-

up supply. Reads and writes are inhibited while the

clock continues to run. The device is programmed seri-

ally through an I

2

C bidirectional bus.

Benefits and Features

•

Enhanced Second Source for the ST M41T00

•

Completely Manages All Timekeeping Functions

•

RTC Counts Seconds, Minutes, Hours, Day, Date,

•

Applications

Portable Instruments

Point-of-Sale Equipment

Medical Equipment

Telecommunications

•

Month, and Year

•

Software Clock Calibration

•

Oscillator Stop Flag

Low-Power Operation Extends Battery Backup Run

Time

•

Low Timekeeping Voltage Down to 1.3V

•

Automatic Power-Fail Detect and Switch Circuitry

•

Trickle-Charge Capability

Three Operating Voltage Ranges (1.8V, 3V, and 3.3V)

Supports Systems Using Legacy and Modern Power

Buses

Surface-Mount Package with an Integrated Crystal

(DS1340C) Saves Additional Space and Simplifies

Design

Simple Serial Port Interfaces with Most Microcontrollers

•

Fast (400kHz) I

2

C Interface

8-Pin µSOP or SO Package Minimizes Required

Space

Underwriters Laboratories (UL

®

) Recognized

Typical Operating Circuit

V

CC

CRYSTAL

V

CC

R

PU

R

PU

1

X1

6 SCL

CPU

5 SDA

R

PU

= t

R

/ C

B

GND

4

2

X2

8

V

CC

FT/OUT

7

C1

V

CC

Ordering Information

PART

DS1340Z-18+

DS1340Z-3+

DS1340Z-33+

DS1340U-18+

DS1340U-3+

TEMP RANGE

-40°C to +85°C

PIN-

PACKAGE

8 SO

(0.150in)

8 SO

(0.150in)

8 SO

(0.150in)

TOP MARK

†

D1340-18

DS1340-3

D134033

1340 -18

1340 -3

1340 -33

DS1340C-18

DS1340C-3

DS1340C-33

DS1340

V

BACKUP

3

-40°C to +85°C 8 μSOP

-40°C to +85°C 16 SO

DS1340U-33+

DS1340C-18#

DS1340C-3#

DS1340C-33#

+Denotes

a lead(Pb)-free/RoHS-compliant package.

#Denotes

a RoHS-compliant device that may include lead(Pb)

that is exempt under RoHS requirements. The lead finish is

JESD97 category e3, and is compatible with both lead-based

and lead-free soldering processes.

†

A "+" anywhere on the top mark denotes a lead(Pb)-free device.

A "#" denotes a RoHS-compliant device.

Pin Configurations appear at end of data sheet.

UL is a registered trademark of Underwriters Laboratories Inc.

19-5578; Rev 9; 4/15

DS1340

I

2

C RTC with Trickle Charger

Absolute Maximum Ratings

Voltage Range on V

CC

or V

BACKUP

Pins

Relative to Ground.............................................-0.3V to +6.0V

Voltage Range on SDA, SCL, and FT/OUT

Relative to Ground..................................-0.3V to (V

CC

+ 0.3V)

Operating Temperature Range ...........................-40°C to +85°C

Storage Temperature Range .............................-55°C to +125°C

Lead Temperature (soldering, 10s) .................................+260°C

Soldering Temperature (reflow) .......................................+260°C

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

absolute maximum rating conditions for extended periods may affect device reliability.

Recommended DC Operating Conditions

(V

CC

= V

CC MIN

to V

CC MAX

, T

A

= -40°C to +85°C, unless otherwise noted. Typical values are at V

CC

= 3.3V, T

A

= +25°C, unless

otherwise noted.) (Note 1)

PARAMETER

Supply Voltage (Note 2)

Input Logic 1 (SDA, SCL)

Input Logic 0 (SDA, SCL)

Supply Voltage, Pullup

(FT/OUT, SDA, SCL), V

CC

= 0V

Backup Supply Voltage (Note 2)

SYMBOL

DS1340-18

V

CC

V

IH

V

IL

V

PU

DS1340-3

DS1340-33

(Note 2)

DS1340-18

V

BACKUP

R1

Trickle-Charge Current-Limiting

Resistors

R2

R3

Power-Fail Voltage (Note 2)

Input Leakage (SCL, CLK)

I/O Leakage (SDA, FT/OUT)

SDA Logic 0 Output

V

PF

I

LI

I

LO

I

OLSDA

V

CC

> 2V; V

OL

= 0.4V

1.7V < V

CC

< 2V; V

OL

= 0.2 x V

CC

V

CC

> 2V; V

OL

= 0.4V

1.7V < V

CC

< 2V; V

OL

= 0.2 x V

CC

1.3V < V

CC

< 1.7V; V

OL

= 0.2x V

CC

DS1340-18; V

CC

= 1.89V

Active Supply Current (Note 7)

I

CCA

DS1340-3; V

CC

= 3.3V

DS1340-33; V

CC

= 5.5V

DS1340-18; V

CC

= 1.89V

Standby Current (Note 8)

V

BACKUP

Leakage Current

I

CCS

DS1340-3; V

CC

= 3.3V

DS1340-33; V

CC

= 5.5V

I

BACKUPLKG

V

BACKUP

= 3.7V

72

108

192

60

81

100

DS1340-3

DS1340-33

(Notes 3, 4)

(Note 5)

(Note 6)

DS1340-18

DS1340-3

DS1340-33

1.51

2.45

2.70

-1

1.3

250

2000

4000

1.6

2.6

2.88

1.71

2.7

2.97

+1

3.0

250

150

200

300

100

125

150

100

nA

μA

mA

μA

V

CONDITIONS

MIN

1.71

2.7

2.97

0.7 x V

CC

-0.3

TYP

1.8

3.0

3.3

MAX

5.5

V

CC

+ 0.3

+0.3 x V

CC

5.5

3.7

5.5

V

UNITS

FT/OUT Logic 0 Output

I

OLSQW

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Maxim Integrated | 2

DS1340

I

2

C RTC with Trickle Charger

DC Electrical Characteristics

(V

CC

= 0V, V

BACKUP

= 3.7V, T

A

= -40°C to +85°C, unless otherwise noted.) (Note 1)

PARAMETER

SYMBOL

I

BACKUP1

V

BACKUP

Current

I

BACKUP2

I

BACKUP3

V

BACKUP

Data-Retention Current

CONDITIONS

OSC ON, FT = 0 (Note 9)

OSC ON, FT = 1 (Note 9)

OSC ON, FT = 0, V

BACKUP

= 3.0V,

T

A

= +25°C (Notes 9, 10)

MIN

TYP

800

850

800

25.0

MAX

1150

1250

1000

100

nA

UNITS

I

BACKUPDR

OSC OFF

AC Electrical Characteristics

(V

CC

= V

CC MIN

to V

CC MAX

, T

A

= -40°C to +85°C, unless otherwise noted.) (Notes 1,14, Figure 1)

PARAMETER

SCL Clock Frequency

Bus Free Time Between STOP

and START Conditions

Hold Time (Repeated) START

Condition (Note 11)

Low Period of SCL Clock

High Period of SCL Clock

Data Hold Time (Notes 12, 13)

Data Setup Time (Note 14)

START Setup Time

Rise Time of SDA and SCL

Signals (Note 15)

Fall Time of SDA and SCL

Signals (Note 15)

Setup Time for STOP Condition

Capacitive Load for Each Bus

Line

I/O Capacitance (SCL, SDA)

Pulse Width of Spikes that Must

be Suppressed by the Input

Filter

Oscillator Stop Flag (OSF) Delay

SYMBOL

f

SCL

t

BUF

t

HD:STA

t

LOW

t

HIGH

t

HD:DAT

t

SU:DAT

t

SU:STA

t

R

t

F

t

SU:STO

C

B

C

I/O

t

SP

t

OSF

Fast mode

(Note 16)

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

Standard mode

Fast mode

(Note 15)

10

30

100

CONDITIONS

Standard mode

MIN

0

100

4.7

1.3

4.0

0.6

4.7

1.3

4.0

0.6

0

250

100

4.7

0.6

20 + 0.1C

B

20 + 0.1C

B

20 + 0.1C

B

20 + 0.1C

B

4.7

0.6

400

1000

300

0.9

TYP

MAX

100

400

UNITS

kHz

μs

ns

μs

ns

μs

pF

ns

ms

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Maxim Integrated | 3

DS1340

I

2

C RTC with Trickle Charger

Power-Up/Power-Down Characteristics

(T

A

= -40°C to +85°C) (Figure 2)

PARAMETER

Recovery at Power-Up

V

CC

Fall Time; V

PF(MAX)

to

V

PF(MIN)

V

CC

Rise Time; V

PF(MIN)

to

V

PF(MAX)

SYMBOL

t

REC

t

VCCF

t

VCCR

(Note 17)

300

0

CONDITIONS

MIN

TYP

MAX

2

UNITS

ms

µs

WARNING:

Under no circumstances are negative undershoots, of any amplitude, allowed when device is in battery-backup mode.

Note 1:

Note 2:

Note 3:

Note 4:

Note 5:

Note 6:

Note 7:

Note 8:

Note 9:

Note 10:

Note 11:

Note 12:

Note 13:

Note 14:

Limits at -40°C are guaranteed by design and not production tested.

All voltages are referenced to ground.

Measured at V

CC

= typ, V

BACKUP

= 0V, register 08h = A5h.

The use of the 250Ω trickle-charge resistor is not allowed at V

CC

> 3.63V and should not be enabled.

Measured at V

CC

= typ, V

BACKUP

= 0V, register 08h = A6h.

Measured at V

CC

= typ, V

BACKUP

= 0V, register 08h = A7h.

I

CCA

—SCL clocking at max frequency = 400kHz.

Specified with I

2

C bus inactive.

Measured with a 32.768kHz crystal attached to the X1 and X2 pins.

Limits at +25°C are guaranteed by design and not production tested.

After this period, the first clock pulse is generated.

A device must internally provide a hold time of at least 300ns for the SDA signal (referred to as the V

IH(MIN)

of the SCL

signal) to bridge the undefined region of the falling edge of SCL.

The maximum t

HD:DAT

only has to be met if the device does not stretch the low period (t

LOW

) of the SCL signal.

A fast-mode device can be used in a standard-mode system, but the requirement t

SU:DAT

≥

to 250ns must be met. This

is automatically the case if the device does not stretch the low period of the SCL signal. If such a device does stretch the

low period of the SCL signal, it must output the next data bit to the SDA line t

R MAX

+ t

SU:DAT

= 1000 + 250 = 1250ns

before the SCL line is released.

C

B

—total capacitance of one bus line in pF.

The parameter t

OSF

is the period of time the oscillator must be stopped for the OSF flag to be set over the 0V

≤

V

CC

≤

V

CCMAX

and 1.3V

≤

V

BAT

≤

3.7V range.

This delay applies only if the oscillator is enabled and running. If the oscillator is disabled or stopped, no power-up delay

occurs.

Note 15:

Note 16:

Note 17:

SDA

t

BUF

t

F

t

LOW

SCL

t

HD:STA

t

SP

t

HIGH

t

HD:STA

t

R

t

HD:DAT

STOP

START

t

SU:DAT

REPEATED

START

t

SU:STA

t

SU:STO

NOTE:

TIMING IS REFERENCED TO V

IL(MAX)

AND V

IH(MIN)

.

Figure 1. Data Transfer on I

2

C Serial Bus

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Maxim Integrated | 4

DS1340

I

2

C RTC with Trickle Charger

V

CC

V

PF(MAX)

V

PF(MIN)

V

PF

V

PF

t

F

t

R

t

REC

INPUTS

RECOGNIZED

DON'T CARE

RECOGNIZED

HIGH-Z

OUTPUTS

VALID

Figure 2. Power-Up/Power-Down Timing

Typical Operating Characteristics

(V

CC

= +3.3V, T

A

= +25°C, unless otherwise noted.)

I

CCSA

vs. V

CC

FT = 0

DS1340 toc01

I

CCS

vs. V

CC

FT = 0

DS1340 toc02

I

BACKUP1

(FT = 0) vs. V

BACKUP

800

SUPPLY CURRENT (nA)

750

700

650

600

550

500

DS1340 toc03

250

150

125

SUPPLY CURRENT (μA)

100

-3.0V

75

50

25

-1.8V

850

200

SUPPLY CURRENT (μA)

-3.3V

150

100

50

450

0

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

V

CC

(V)

0

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

V

CC

(V)

400

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

V

BACKUP

(V)

I

BACKUP2

(FT = 1) vs. V

BACKUP

DS1340 toc04

I

BACKUP3

vs. TEMPERATURE

850

800

SUPPLY CURRENT (nA)

FREQUENCY (Hz)

750

700

650

600

550

500

V

BACKUP

= 3.0V

DS1340 toc05

OSCILLATOR FREQUENCY vs. SUPPLY VOLTAGE

(FT x 64)

DS1340 toc06

850

800

SUPPLY CURRENT (nA)

750

700

650

600

550

500

450

400

32768.6

32768.5

32768.4

32768.3

32768.2

32768.1

32768.0

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

V

BACKUP

(V)

-40

-20

0

20

40

60

80

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

V

BACKUP

(V)

TEMPERATURE (°C)

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Parameter Name	Attribute value
type	clock/calendar
characteristic	Leap Year, Trickle Charger
storage	-
Time format	HH:MM:SS (24 hours)
date format	YY-MM-DD-dd
interface	I²C, 2-wire serial port
Voltage - Power	2.7 V ~ 5.5 V
Voltage - power supply, battery	1.3 V ~ 3.7 V
Current - Timing (maximum)	125µA @ 3.3V
Operating temperature	-40°C ~ 85°C
Installation type	surface mount
Package/casing	8-TSSOP, 8-MSOP (0.118", 3.00mm wide)
Supplier device packaging	8-uSOP

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