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Numéro de sérieDS1338
CategorieTiming Circuits => Real Time Clocks
DescriptionI²C RTC With 56-Byte NV RAM
The DS1338 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I²C interface. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date 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 DS1338 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operatio
SociétéMaxim Integrated Products
DatasheetTélécharger DS1338 datasheet
 
 
  • Description courte

  • The DS1338 serial real-time clock (RTC) is a lowpower, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I2C interface. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the or 12-hour format with AM/PM indicator. The DS1338 has a built-in powersense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation

    FEATURES

    RTC Counts Seconds, Minutes, Hours, Date of the Month, Day of the Week, and Year with Leap-Year Compensation Valid to 2100 Available in a Surface-Mount Package with an Integrated Crystal (DS1338C) 56-Byte Battery-Backed General-Purpose RAM with Unlimited Writes I2C Serial Interface Programmable Square-Wave Output Signal Automatic Power-Fail Detect and Switch Circuitry to +85°C Operating Temperature Range Underwriters Laboratory (UL) Recognized

    APPLICATIONS

    Handhelds (GPS, POS Terminal) Consumer Electronics (Set-Top Box, Digital Recording, Network Appliance) Office Equipment (Fax/Printer, Copier) Medical (Glucometer, Medicine Dispenser) Telecommunications (Router, Switcher, Server) Other (Utility Meter, Vending Machine, Thermostat, Modem)

    rr = second line, revision level + 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 denotes a lead-free device. A denotes a RoHS-compliant device. DS1338C-18#

    Voltage Range on Any Pin Relative to +6.0V Operating Temperature to +85°C Storage Temperature to +125°C Soldering Temperature.........................See precautions in the Handling, PCB Layout, and Assembly Section.

    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.

    (VCC = VCC(MIN) to VCC(MAX), to +85°C, unless otherwise noted. Typical values are at VCC = +25°C, unless otherwise noted.) (Note 1) PARAMETER Supply Voltage Logic 1 Logic 0 Power-Fail Voltage VBAT Input Voltage SYMBOL VCC VIH VIL VPF VBAT CONDITIONS DS1338-3 DS1338-33 (Note 2) (Note DS1338-3 DS1338-33 (Note 2) MIN x VCC TYP 3.0 3.3 MAX 3.3 5.5 VCC 0.3 x VCC UNITS

    (VCC = VCC(MIN) to VCC(MAX), to +85°C, unless otherwise noted. Typical values are at VCC = +25°C, unless otherwise noted.) (Note 1) PARAMETER Input Leakage I/O Leakage SDA Logic 0 Output SYMBOL ILI ILO IOLSDA CONDITIONS (Note 3) (Note 4) VCC > 2V; VOL = 0.4V VCC < 2V; VOL 0.2 x VCC > 2V; VOL 1.71V < VCC < 2V; VOL = 0.2 VCC 1.3V < VCC < 1.71V; VOL = 0.2 VCC DS1338-18 DS1338-3 VCC 3.63V < VCC DS1338-18 DS1338-3 VCC 3.63V < VCC 5.5V MIN TYP MAX mA A UNITS A mA

    (VCC to +85°C, unless otherwise noted. Typical values are at VBAT = +25°C, unless otherwise noted.) (Note 1) PARAMETER VBAT Current (OSC ON); VBAT = 3.7V, SQW/OUT OFF (Note 7) VBAT Current (OSC ON); VBAT = 3.7V, SQW/OUT ON (32kHz) (Note 7) VBAT Data-Retention Current (Osc Off); VBAT = 3.7V (Note 7) SYMBOL IBATOSC1 IBATOSC2 IBATDAT MIN TYP 1025 10 MAX 1400 100 UNITS nA

    (VCC = VCC(MIN) to VCC(MAX), to +85°C) (Note 1) PARAMETER SCL Clock Frequency Bus Free Time Between STOP and START Condition Hold Time (Repeated) START Condition (Note 8) LOW Period of SCL Clock HIGH Period of SCL Clock Setup Time for Repeated START Condition Data Hold Time (Notes 9, 10) Data Setup Time (Note 11) Rise Time of Both SDA and SCL Signals (Note 12) Fall Time of Both SDA and SCL Signals (Note 12) Setup Time for STOP Condition Capacitive Load for Each Bus Line I/O Capacitance (SDA, SCL) Oscillator Stop Flag (OSF) Delay SYMBOL fSCL tBUF tHD:STA tLOW tHIGH tSU:STA tHD:DAT tSU:DAT tR tF tSU:STO CB CI/O tOSF CONDITION 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 Standard mode (Note 12) (Note 13) (Note 14) 100 MIN + 0.1CB TYP MAX 400 100 UNITS kHz pF ms