Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsIntegrated Circuits (ICs)Linear IC

1 of 19

REV: 092006

DS1339

C Serial Real-Time Clock

GENERAL DESCRIPTION

The DS1339 serial real-time clock (RTC) is a low-

power clock/date device with two programmable time-

of-day alarms and a programmable square-wave

output. Address and data are transferred serially

through an I

C bus. The clock/date provides 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

AM/PM indicator. The DS1339 has a built-in power-

sense circuit that detects power failures and

automatically switches to the backup supply,

maintaining time, date, and alarm operation.

APPLICATIONS

Handhelds (GPS, POS Terminals)

Consumer Electronics (Set-Top Box, Digital

Recording, Network Appliance)

Office Equipment (Fax/Printers, Copier)

Medical (Glucometer, Medicine Dispenser)

Telecommunications (Routers, Switches, Servers)

Other (Utility Meter, Vending Machine, Thermostat,

Modem

)

FEATURES

 Real-Time Clock (RTC) Counts Seconds, Minutes,

Hours, Day, Date, Month, and Year with Leap-

Year Compensation Valid Up to 2100

 Available in a Surface-Mount Package with an

Integrated Crystal (DS1339C)

 I

C Serial Interface

 Two Time-of-Day Alarms

 Programmable Square-Wave Output

 Oscillator Stop Flag

 Automatic Power-Fail Detect and Switch Circuitry

 Trickle-Charge Capability

 Underwriters Laboratory (UL) Recognized

Pin Configurations appear at end of data sheet.

ORDERING INFORMATION

PART TEMP RANGE VOLTAGE (V) PIN-PACKAGE TOP MARK†

DS1339C-2 -40°C to +85°C 2.0 16 SO (300 mils) DS1339C-2

DS1339C-2# -40°C to +85°C 2.0 16 SO (300 mils) DS1339C-2

DS1339C-3 -40°C to +85°C 3.0 16 SO (300 mils) DS1339C-3

DS1339C-3# -40°C to +85°C 3.0 16 SO (300 mils) DS1339C-3

DS1339C-33 -40°C to +85°C 3.3 16 SO (300 mils) DS1339C-33

DS1339C-33# -40°C to +85°C 3.3 16 SO (300 mils) DS1339C-33

DS1339U-2 -40°C to +85°C 2.0

8 µSOP

1339 rr-2

DS1339U-2+ -40°C to +85°C 2.0

8 µSOP

1339 rr-2

DS1339U-3 -40°C to +85°C 3.0

8 µSOP

1339 rr-3

DS1339U-3+ -40°C to +85°C 3.0

8 µSOP

1339 rr-3

DS1339U-33 -40°C to +85°C 3.3

8 µSOP

1339 rr-33

DS1339U-33+ -40°C to +85°C 3.3

8 µSOP

1339 rr-33

+ Denotes a lead-free/RoHS-compliant device.

# Denotes a RoHS-compliant device that may include lead that is exempt under the 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 indicates a lead-free device. A “#” denotes a RoHS-compliant device. rr = second line, revision code

www.maxim-ic.com

Summary of content (19 pages)

PAGE 1
DS1339 I C Serial Real-Time Clock 2 www.maxim-ic.com GENERAL DESCRIPTION FEATURES The DS1339 serial real-time clock (RTC) is a lowpower clock/date device with two programmable timeof-day alarms and a programmable square-wave output. Address and data are transferred serially through an I2C bus. The clock/date provides seconds, minutes, hours, day, date, month, and year information.
PAGE 2
DS1339 I2C Serial Real-Time Clock ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground………………………………………………………………-0.3V to +6.0V Operating Temperature Range (Noncondensing)………………………………………………………….-40°C to +85°C Storage Temperature Range………………………………………………………………………………..-55°C to +125°C Soldering Temperature Range………….See precautions in the Handling, PC Board Layout, and Assembly section. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
PAGE 3
DS1339 I2C Serial Real-Time Clock DC ELECTRICAL CHARACTERISTICS (continued) (VCC = MIN to MAX, TA = -40°C to +85°C.
PAGE 4
DS1339 I2C Serial Real-Time Clock AC ELECTRICAL CHARACTERISTICS (VCC = MIN to MAX, TA = -40°C to +85°C.
PAGE 5
DS1339 I2C Serial Real-Time Clock POWER-UP/DOWN CHARACTERISTICS (TA = -40°C to +85°C) (Note 1, Figure 1) PARAMETER SYMBOL CONDITIONS MIN (Note 15) TYP MAX UNITS 2 ms Recovery at Power-Up tREC VCC Fall Time; VPF(MAX) to VPF(MIN) tVCCF 300 µs VCC Rise Time; VPF(MIN) to VPF(MAX) tVCCR 0 µs WARNING: Under no circumstances are negative undershoots, of any amplitude, allowed when device is in battery-backup mode. Note 1: Limits at -40°C are guaranteed by design and are not production tested.
PAGE 6
DS1339 I2C Serial Real-Time Clock Figure 2. Timing Diagram Figure 3. Block Diagram 1Hz/4.096kHz/8.192kHz/32.
PAGE 7
DS1339 I2C Serial Real-Time Clock TYPICAL OPERATING CHARACTERISTICS (VCC = 3.3v, TA = +25°C, unless otherwise noted.) IBACKUP vs. VBACKUP ICC vs. VCC V CC=0V RS1=RS0=1 250 900 SCL=400kHz ICCA 850 800 IBATOSC2 SQWE = 1) 200 ( SUPPLY CURRENT (uA) SUPPLY CURRENT (nA) 750 700 650 IBAT OSC1 (SQWE = 0) 600 550 500 450 150 SCL=SDA=0Hz ICCS 100 400 350 300 1.3 1.8 2.3 2.8 3.3 3.8 VBACKUP (V) 4.3 4.8 IBACKUP vs. Temperature 50 5.3 1.8 V CC=0V 2.3 2.8 3.3 3.8 VCC (V) 4.3 4.8 5.
PAGE 8
DS1339 I2C Serial Real-Time Clock PIN DESCRIPTION PIN SO µSOP NAME FUNCTION Connections for Standard 32.768kHz Quartz Crystal. The internal oscillator circuitry is designed for operation with a crystal having a specified load capacitance (CL) of 6pF. An external 32.768kHz oscillator can also drive the DS1339. In this configuration, the X1 pin is connected to the external oscillator signal and the X2 pin is floated.
PAGE 9
DS1339 I2C Serial Real-Time Clock DETAILED DESCRIPTION The DS1339 serial real-time clock (RTC) is a low-power clock/date device with two programmable time-of-day alarms and a programmable square-wave output. Address and data are transferred serially through an I2C bus. The clock/date provides 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.
PAGE 10
DS1339 I2C Serial Real-Time Clock Table 2. Crystal Specifications* PARAMETER SYMBOL Nominal Frequency fO Series Resistance ESR Load Capacitance CL MIN TYP MAX 32.768 kHz 45 6 UNITS kΩ 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.
PAGE 11
DS1339 I2C Serial Real-Time Clock ADDRESS MAP Table 3 shows the address map for the DS1339 registers. During a multibyte access, when the address pointer reaches the end of the register space (10h), it wraps around to location 00h. On an I2C START, STOP, or address pointer incrementing to location 00h, the current time is transferred to a second set of registers. The time information is read from these secondary registers, while the clock may continue to run.
PAGE 12
DS1339 I2C Serial Real-Time Clock TIME AND DATE OPERATION The time and date information is obtained by reading the appropriate register bytes. Table 3 shows the RTC registers. The time and date are set or initialized by writing the appropriate register bytes. The contents of the time and date registers are in the BCD format. The DS1339 can be run in either 12-hour or 24-hour mode. Bit 6 of the hours register is defined as the 12- or 24-hour mode-select bit. When high, the 12-hour mode is selected.
PAGE 13
DS1339 I2C Serial Real-Time Clock Table 4.
PAGE 14
DS1339 I2C Serial Real-Time Clock Bit 2: Interrupt Control (INTCN). This bit controls the relationship between the two alarms and the interrupt output pins. When the INTCN bit is set to logic 1, a match between the timekeeping registers and the alarm 1 or alarm 2 registers activate the SQW/INT pin (provided that the alarm is enabled). When the INTCN bit is set to logic 0, a square wave is output on the SQW/INT pin. This bit is set to logic 0 when power is first applied.
PAGE 15
DS1339 I2C Serial Real-Time Clock TRICKLE CHARGER REGISTER (10h) The simplified schematic in Figure 5 shows the basic components of the trickle charger. The trickle-charge select (TCS) bits (bits 4 to 7) control the selection of the trickle charger. To prevent accidental enabling, only a pattern on 1010 enables the trickle charger. All other patterns disable the trickle charger. The trickle charger is disabled when power is first applied.
PAGE 16
DS1339 I2C Serial Real-Time Clock Figure 5. Programmable Trickle Charger R1 VCC 250Ω VBACKUP R2 2kΩ R3 4kΩ 1 OF 16 SELECT NOTE: ONLY 1010 ENABLES CHARGER TCS3 BIT 7 TCS2 BIT 6 TCS1 BIT 5 TCS0 BIT 4 1 OF 2 SELECT DS1 BIT 3 1 OF 3 SELECT DS0 BIT 2 ROUT1 BIT 1 ROUT0 BIT 0 TCS0-3 = TRICKLE CHARGER SELECT DS0-1 = DIODE SELECT ROUT0-1 = RESISTOR SELECT TRICKLE CHARGE REGISTER I2C SERIAL DATA BUS The DS1339 supports the I2C bus protocol.
PAGE 17
DS1339 I2C Serial Real-Time Clock Each data transfer is initiated with a START condition and terminated with a STOP condition. The number of data bytes transferred between START and STOP conditions is not limited, and is determined by the master device. The information is transferred byte-wise and each receiver acknowledges with a ninth bit. Acknowledge: Each receiving device, when addressed, is obliged to generate an acknowledge after the reception of each byte.
PAGE 18
DS1339 I2C Serial Real-Time Clock sets the register pointer on the DS1339, with the DS1339 acknowledging the transfer. The master may then transmit zero or more bytes of data, with the DS1339 acknowledging each byte received. The address pointer increments after each data byte is transferred. The master generates a STOP condition to terminate the data write. 2) Slave Transmitter Mode (Read Mode): The first byte is received and handled as in the slave receiver mode.
PAGE 19
DS1339 I2C Serial Real-Time Clock HANDLING, PC BOARD LAYOUT, AND ASSEMBLY The DS1339C package contains a quartz tuning-fork crystal. Pick-and-place equipment may be used, but precautions should be taken to ensure that excessive shocks are avoided. Ultrasonic cleaning should be avoided to prevent damage to the crystal. Avoid running signal traces under the package, unless a ground plane is placed between the package and the signal line. All N.C. (no connect) pins must be connected to ground.