Rainbow Electronics DS1393 User Manual

General Description

The low-voltage serial-peripheral interface (SPI™) DS1390/DS1391 and the low-voltage 3-wire DS1392/ DS1393 real-time clocks (RTCs) are clocks/calendars that provide hundredths of a second, seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator. One programmable time-of-day alarm is provided. A temperature-compensated voltage reference monitors the status of VCCand automatically switches to the backup supply if a power failure is detected. On the DS1390, a single open-drain output provides a CPU interrupt or a square wave at one of four selectable frequencies. The DS1391 replaces the SQW/INT pin with a RST output/debounced input.

The DS1390 and DS1391 are programmed serially through an SPI-compatible, bidirectional bus. The DS1392 and DS1393 communicate over a 3-wire serial bus, and the extra pin is used for either a separate interrupt pin or a RST output/debounced input.

All four devices are available in a 10-pin µSOP package, and are rated over the industrial temperature range.

Applications

Hand-Held Devices

GPS/Telematics Devices

Embedded Time Stamping

Medical Devices

Features

♦ Real-Time Clock Counts Hundredths of Seconds,

Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap-Year Compensation Valid Up to 2100

♦ Output Pin Configurable as Interrupt or Square

Wave with Programmable Frequency of

32.768kHz, 8.192kHz, 4.096kHz, or 1Hz (DS1390/DS1393 Only)

♦ One Time-of-Day Alarm

♦ Power-Fail Detect and Switch Circuitry

♦ Reset Output/Debounced Input (DS1391/DS1393)

♦ Separate SQW and INT Output (DS1392)

♦ Trickle-Charge Capability

♦ SPI Supports Modes 1 and 3 (DS1390/DS1391)

♦ 3-Wire Interface (DS1392/DS1393)

♦ 4MHz at 3.0V and 3.3V

♦ 1MHz at 1.8V

♦ Three Operating Voltages: 1.8V ±5%, 3.0V ±10%,

and 2.97 to 5.5V

♦ Industrial Temperature Range: -40°C to +85°C

♦ Underwriters Laboratory (UL) Recognized

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with

Trickle Charger

______________________________________________ Maxim Integrated Products 1

Ordering Information

Rev 0; 7/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Typical Operating Circuits and Pin Configurations appear at end of the data sheet.

Where “rr” is a revision code on the second line of the top mark.

PART

PIN-

TOP MARK

DS1390U-18

10 µSOP

DS1390 rr-18

DS1390U-3

10 µSOP DS1390 rr-3

DS1390U-33

10 µSOP

DS1390 rr-33

DS1391U-18

10 µSOP

DS1391 rr-18

DS1391U-3

10 µSOP DS1391 rr-3

DS1391U-33

10 µSOP

DS1391 rr-33

DS1392U-18

10 µSOP

DS1393 rr-18

DS1392U-3

10 µSOP DS1392 rr-3

DS1392U-33

10 µSOP

DS1392 rr-33

DS1393U-18

10 µSOP

DS1393 rr-18

DS1393U-3

10 µSOP DS1393 rr-3

DS1393U-33

-40°C to +85°C

10 µSOP

DS1393 rr-33

SPI is a trademark of Motorola, Inc.

TEMP RANGE

-40°C to +85°C

PACKAGE

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with Trickle Charger

2 _____________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

RECOMMENDED DC OPERATING CONDITIONS

(VCC= V

CC(MIN)

to V

CC(MAX)

, TA= -40°C to +85°C, unless otherwise noted. Typical values are at nominal supply voltage and TA= +25°C,

unless otherwise noted.) (Note 1)

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.

Voltage Range on VCCPin Relative to Ground .....-0.3V to +6.0V

Voltage Range on Inputs 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

Soldering Temperature .......................................See IPC/JEDEC

J-STD-020A Specification

PARAMETER

CONDITIONS

UNITS

DS139x-33

3.3

DS139x-3 2.7 3.0 3.3

Supply Voltage (Note 2) V

CC

DS139x-18

1.8

V

Logic 1 V

IH

(Note 2)

0.7 x

VCC +

0.5

V

Logic 0 V

IL

(Note 2)

+0.3 x

V

Supply Voltage, Pullup

SQW/INT, SQW, INT, VCC = 0V

V

PU

(Note 2) 5.5 V

-33 1.3

)

-3 1.3 3.0 3.7

V

BACKUP

Voltage (Note 2)

-18 1.3 3.0 3.7

V

-33

-3

2.6

Power-Fail Voltage (Note 2) V

PF

-18

1.6

V

R1 (Notes 3, 4)

R2 (Notes 3, 5)

Trickle-Charge Current-Limiting Resistors

R3 (Notes 3, 6)

Ω

Input Leakage I

LI

(Note 7) -1 +1 µA

I/O Leakage I

LO

(Note 8) -1 +1 µA

RST Pin I/O Leakage I

LORST

(Note 9)

µA

-33, -3 (V

OH

= 0.85 x VCC)-1

DOUT Logic 1 Output

-18 (V

OH

= 0.80 x VCC)

mA

-33, -3 (V

OL

= 0.15 x VCC)3

DOUT Logic 0 Output

-18 (V

OL

= 0.20 x VCC)2

mA

VCC > 1.71V; VOL = 0.4V 3.0 mA

Logic 0 Output (DS1390/DS1393 SQW/INT; DS1392 SQW, INT; DS1391/DS1393 RST)

I

OLSIR

1.3V < VCC < 1.71V; VOL = 0.4V 250 µA

-33 2

-3 2

mA

VCC Active Supply Current (Note 10)

I

CCA

-18 500 µA

SYMBOL

MIN TYP MAX

2.97

5.50

V

BACKUP

I

OHDOUT

I

OHDOUT

1.71

V

CC

-0.3

3.0 V

2.70 2.88 2.97

2.45

1.51

250

2000

4000

-200 +10

1.89

V

CC(MAX

2.70

1.71

0.750

CC

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with

Trickle Charger

_____________________________________________________________________ 3

RECOMMENDED DC OPERATING CONDITIONS (continued)

(VCC= V

CC(MIN)

to V

CC(MAX)

, TA= -40°C to +85°C, unless otherwise noted. Typical values are at nominal supply voltage and TA= +25°C,

unless otherwise noted.) (Note 1)

PARAMETER

CONDITIONS

UNITS

-33

175

-3 80 125

VCC Standby Current (Note 11)

I

CCS

-18 60 100

µA

V

BACKUP

Leakage Current

(V

BACKUP

= 3.7V,

V

CC

= V

CC(MAX)

)

15 100 nA

DC ELECTRICAL CHARACTERISTICS

(VCC= 0V, V

BACKUP

= 3.7V, TA= -40°C to +85°C, unless otherwise noted.) (Note 1)

PARAMETER

CONDITIONS

UNITS

V

BACKUP

Current OSC On,

SQW Off

(Note 12)

nA

V

BACKUP

Current OSC On,

SQW On (32kHz)

(Note 12)

nA

V

BACKUP

Current OSC On,

SQW On, V

BACKUP

= 3.0V,

T

A

= +25°C

(Note 12)

nA

V

BACKUP

Current, OSC Off

(Data Retention)

(Note 12) 25 100 nA

AC ELECTRICAL CHARACTERISTICS—SPI INTERFACE

(VCC= V

CC(MIN)

to V

CC(MAX)

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

PARAMETER

CONDITION

UNITS

2.7V ≤ VCC ≤ 5.5V 4

SCLK Frequency (Note 13) f

SCLK

1.71V ≤ VCC ≤ 1.89V 1

MHz

Data to SCLK Setup t

DC

(Notes 13, 14) 30 ns

SCLK to Data Hold t

CDH

(Notes 13, 14) 30 ns

2.7V ≤ VCC ≤ 5.5V 80

SCLK to Data Valid (Notes 13, 14, 15)

t

CDD

1.71V ≤ VCC ≤ 1.89V 160

ns

2.7V ≤ VCC ≤. 5.5V

SCLK Low Time (Note 13) t

CL

1.71V ≤ VCC ≤ 1.89V

ns

2.7V ≤ VCC ≤ 5.5V

SCLK High Time (Note 13) t

CH

1.71V ≤ VCC ≤ 1.89V

ns

SCLK Rise and Fall tR, t

F

200 ns

CS to SCLK Setup (Note 13) t

CC

ns

SCLK to CS Hold (Note 13) t

CCH

ns

2.7V ≤ VCC ≤. 5.5V

CS Inactive Time (Note 13) t

CWH

1.71V ≤ VCC ≤ 1.89V

ns

CS to Output High Impedance t

CDZ

(Notes 13, 14) 40 ns

SYMBOL

I

BACKUPLKG

SYMBOL

I

BACKUP1

I

BACKUP2

I

BACKUP3

I

BACKUPDR

MIN TYP MAX

115

MIN TYP MAX

500 1000

600 1150

600 1000

SYMBOL

MIN TYP MAX

110

400

110

400

100

400

500

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with Trickle Charger

4 _____________________________________________________________________

CS

SCLK

DIN

W/R

t

DC

t

CL

t

CH

t

CDD

t

CDZ

t

CDH

t

CC

t

R

t

F

A6

A0

D0

WRITE ADDRESS BYTE

NOTE: SCLK CAN BE EITHER POLARITY, SHOWN FOR CPOL = 1.

READ DATA BYTE

DOUT

D7

Figure 1. Timing Diagram—SPI Read Transfer

CS

SCLK

DIN

W/R

t

DC

t

CDH

t

CL

t

CH

t

CCH

t

CWH

t

F

t

R

t

CC

A6

A0

WRITE ADDRESS BYTE

WRITE DATA BYTE

D7 D0

Figure 2. Timing Diagram—SPI Write Transfer

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with

Trickle Charger

_____________________________________________________________________ 5

AC ELECTRICAL CHARACTERISTICS—3-WIRE INTERFACE

(VCC= V

CC(MIN)

to V

CC(MAX)

, TA= -40°C to +85°C.) (Note 1) (Figures 3, 4)

PARAMETER

CONDITION

UNITS

2.7V ≤ VCC ≤ 5.5V 4

SCLK Frequency (Note 13) f

SCLK

1.71V ≤ VCC ≤ 1.89V 1

MHz

Data to SCLK Setup t

DC

(Notes 13, 14) 30 ns

SCLK to Data Hold t

CDH

(Notes 13, 14) 30 ns

2.7V ≤ VCC ≤ 5.5V 80

SCLK to Data Valid (Notes 13, 14, 15)

t

CDD

1.71V ≤ VCC ≤ 1.89V 160

ns

2.7V ≤ VCC ≤ 5.5V

SCLK Low Time (Note 13) t

CL

1.71V ≤ VCC ≤ 1.89V

ns

2.7V ≤ VCC ≤ 5.5V

SCLK High Time (Note 13) t

CH

1.71V ≤ VCC ≤ 1.89V

ns

SCLK Rise and Fall tR, t

F

200 ns

CS to SCLK Setup t

CC

(Note 13)

ns

SCLK to CS Hold t

CCH

(Note 13)

ns

2.7V ≤ VCC ≤ 5.5V

CS Inactive Time (Note 13) t

CWH

1.71V ≤ VCC ≤ 1.89V

ns

CS to Output High Impedance t

CDZ

(Note 13, 14) 40 ns

AC ELECTRICAL CHARACTERISTICS

(VCC= V

CC(MIN)

to V

CC(MAX)

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

PARAMETER

CONDITIONS

UNITS

Pushbutton Debounce PB

DB

200 ms

Reset Active Time t

RST

200 ms

Oscillator Stop Flag (OSF) Delay

t

OSF

(Note 16)

ms

SYMBOL

MIN TYP MAX

110

400

110

400

100

400

500

SYMBOL

MIN TYP MAX

160

100

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with Trickle Charger

6 _____________________________________________________________________

t

DC

t

CL

t

CH

t

CDH

t

CC

t

CDD

t

CDZ

t

R

t

F

A0 A1 R/W

D0 D7

WRITE ADDRESS BYTE

READ DATA BYTE

CE

SCLK

I/O

Figure 3. Timing Diagram—3-Wire Read Transfer

I/O

CE

SCLK

t

DC

t

CL

t

CH

t

CDH

t

CC

t

CCH

t

CWH

t

R

t

F

A0 A1 R/W

D0

D7

WRITE ADDRESS BYTE

WRITE DATA BYTE

Figure 4. Timing Diagram—3-Wire Write Transfer

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with

Trickle Charger

_____________________________________________________________________ 7

OUTPUTS

V

CC

V

PF(MAX)

INPUTS

HIGH-IMPEDANCE

RST

DON'T CARE

VALID

RECOGNIZED

VALID

V

PF(MIN)

t

RST

t

RPU

t

R

t

F

V

PF

V

PF

Figure 5. Power-Up/Down Timing

t

RST

PB

DB

RST

Figure 6. Pushbutton Reset Timing

POWER-UP/POWER-DOWN CHARACTERISTICS

(TA= -40°C to +85°C) (Figures 5, 6)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

VCC Detect to Recognize Inputs (V

CC

Rising)

t

RST

(Note 17)

200 ms

VCC Fall Time; V

PF(MAX)

to

V

PF(MIN)

t

F

µs

VCC Rise Time; V

PF(MIN)

to

V

PF(MAX)

t

R

0µs

160

300

DS1390/DS1391/DS1392/DS1393

Low-Voltage SPI/3-Wire RTCs with Trickle Charger

8 _____________________________________________________________________

CAPACITANCE

(TA= +25°C)

PARAMETER

CONDITIONS

UNITS

Capacitance on All Input Pins C

IN

10 pF

Capacitance on All Output Pins (High Impedance)

C

IO

10 pF

WARNING: Under no circumstances are negative undershoots, of any amplitude, allowed when the device

is in write protection.

Note 1: Limits at -40°C are guaranteed by design and not production tested. Note 2: All voltages are referenced to ground. Note 3: The use of the 250Ω trickle-charge resistor is not allowed at V

CC

> 3.63V and should not be enabled. Use of the diode is

not recommended for V

CC

< 3.0V.

Note 4: Measured at V

CC

= typ, V

BACKUP

= 0V, register 0Fh = A5h.

Note 5: Measured at V

CC

= typ, V

BACKUP

= 0V, register 0Fh = A6h.

Note 6: Measured at V

CC

= typ, V

BACKUP

= 0V, register 0Fh = A7h.

Note 7: SCLK, DIN, CS on DS1390/DS1391; SCLK, and CE on DS1392/DS1393. Note 8: DOUT, SQW/INT (DS1390/DS1393), SQW, and INT (DS1392). Note 9: The RST pin has an internal 50kΩ (typ) pullup resistor to V

CC

.

Note 10: I

CCA

—SCLK clocking at max frequency = 4MHz for 3V and 3.3V versions; 1MHz for 1.8V version; RST (DS1391/DS1393)

inactive. Outputs are open.

Note 11: Specified with bus inactive. Note 12: Measured with a 32.768kHz crystal attached to X1 and X2. Typical values measured at +25°C and 3.0V

BACKUP

.

Note 13: With 50pF load. Note 14: Measured at V

IH

= 0.7 x VDDor VIL= 0.2 x VDD, 10ns rise/fall times.

Note 15: Measured at V

OH

= 0.7 x VDDor VOL= 0.2 x VDD. Measured from the 50% point of SCLK to the VOHminimum of SDO.

Note 16: The parameter t

OSF

is the time that the oscillator must be stopped for the OSF flag to be set over the voltage range of

0 ≤ V

CC

≤ V

CC(MAX)

and 1.3V ≤ V

BAT

≤ 5.5V.

Note 17: This delay applies only if the oscillator is enabled and running. If the EOSC bit is 1, the startup time of the oscillator is

added to this delay.

SYMBOL

MIN TYP MAX