Microchip Technology Inc

MCP7940N

In Production

The MCP7940N series of low-power Real-Time Clocks (RTC) uses digital timing compensation for an accurate clock/calendar, a programmable output control for versatility, and a power sense circuit that automatically switches to the backup supply. Using a low-cost 32.768 kHz crystal, it tracks time using several internal registers. For communication, the MCP7940N uses the I2C™ bus. The clock/calendar automatically adjusts for months with fewer than 31 days, including corrections for leap years. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator and settable alarm(s) to the second, minute, hour, day of the week, date or month. Using the programmable CLKOUT, frequencies of 32.768, 8.192 and 4.096 kHz and 1 Hz can be generated from the external crystal. The device is fully accessible through the serial interface while VCC is between 1.8V and 5.5V, but can operate down to 1.3V for timekeeping and SRAM retention only.

 

    Features

          Timekeeping
          • Battery-Backed Real-Time Clock/Calendar (RTCC)
            • Hours, Minutes, Seconds, Day of Week, Day, Month, Year
            • Leap year compensated  to 2399
            • 12/24 hour modes
          • On-Chip Digital Trimming/Calibration
            • 1 PPM Resolution
            • ±129 PPM Range
          • Dual Programmable Alarms
          • Versatile Output Pin
            • Clock output with selectable frequency
            • Alarm output
            • General Purpose output
          • Power-Fail Time-Stamp
            • Time logged on switchover to and from Battery Backup
          • 64 Bytes Battery-Backed SRAM
          • 2-Wire Serial Interface, I2C™Compatible
            • I2C Clock Frequency up to 400 kHz
          Low-Power
          • Wide Voltage Range
            • Operating Voltage 1.8V to 5.5V
            • Backup Voltage 1.3V to 5.5V
          • Low Typical Timekeeping Current
          • Automatic Switchover to Battery Backup
    Parameter Name
    Value
    Max Communications Speed
    400 kHz
    Pin Count
    8
    Minimum Clock Count (seconds)
    1 sec
    Battery-backed SRAM (Bytes)
    64
    Temperature Range (C)
    -40 to +125
    Documentation
    Data Sheets
    03/20/2014
    1351KB
      Errata
     
     
     
     
    Errata
    12/15/2015
    70KB
      Migration Documents
     
     
     
    Migration Documents
    03/07/2013
    326KB
    Migration Documents
    03/28/2013
    317KB
    Migration Documents
    04/09/2013
    344KB
      Application Notes
     
     
     
    AppNote
    06/23/2016
    154KB
    AppNote
    10/20/2010
    123KB
    AppNote
    03/28/2013
    267KB
    AppNote
    09/13/2016
    303KB
    AppNote
    01/31/2012
    4847KB
    AppNote
    01/25/2013
    246KB
    AppNote
    02/22/2013
    215KB
    AppNote
    09/16/2013
    397KB
    AppNote
    12/01/2015
    161KB
    AppNote
    08/11/2014
    75KB
      Technical Briefs
     
     
     
     
    Tech Briefs
    10/21/2010
    74KB
      Brochures
     
     
     
    Brochures
    07/21/2014
    703KB
    Brochures
    10/27/2010
    141KB
      Gerber Files
     
     
     
     
    Gerber Files
    05/25/2011
    50KB
      Sample Code
     
     
     
    Sample Code
    08/21/2012
    61KB
    Sample Code
    08/21/2012
    152KB
    Pricing & Samples
    All pricing shown in USD only.
    Part Number
    Leads
    Package Type
    Temp Range
    Packing
    1+
    26+
    100+
    1000+
    5000+
    Buy
    Sample
    MCP7940N-E/MS
    8
    MSOP
    -40C to +125C
    TUBE
    0.84
    0.78
    0.74
    0.69
    0.67
     
    MCP7940N-E/SN
    8
    SOIC
    -40C to +125C
    TUBE
    0.80
    0.74
    0.70
    0.66
    0.64
     
    MCP7940N-I/MS
    8
    MSOP
    -40C to +85C
    TUBE
    0.78
    0.72
    0.68
    0.64
    0.62
    MCP7940N-I/P
    8
    PDIP
    -40C to +85C
    TUBE
    0.80
    0.74
    0.70
    0.66
    0.64
    MCP7940N-I/SN
    8
    SOIC
    -40C to +85C
    TUBE
    0.74
    0.68
    0.65
    0.61
    0.59
    MCP7940N-I/ST
    8
    TSSOP
    -40C to +85C
    TUBE
    0.78
    0.72
    0.68
    0.64
    0.62
    MCP7940NT-E/MS
    8
    MSOP
    -40C to +125C
    T/R
    0.84
    0.78
    0.74
    0.69
    0.67
     
    MCP7940NT-E/SN
    8
    SOIC
    -40C to +125C
    T/R
    0.80
    0.74
    0.70
    0.66
    0.64
     
    MCP7940NT-I/MNY
    8
    TDFN
    -40C to +85C
    T/R
    0.82
    0.76
    0.72
    0.68
    0.66
    MCP7940NT-I/MS
    8
    MSOP
    -40C to +85C
    T/R
    0.78
    0.72
    0.68
    0.64
    0.62
     
    MCP7940NT-I/SN
    8
    SOIC
    -40C to +85C
    T/R
    0.74
    0.68
    0.65
    0.61
    0.59
     
    MCP7940NT-I/ST
    8
    TSSOP
    -40C to +85C
    T/R
    0.78
    0.72
    0.68
    0.64
    0.62
     

    ** Device not available to purchase online. Please contact a sales office for pricing information.
    Open a microchipDIRECT account today!

    Development Tools
    • Demo & Eval Boards
    • MCP79410 RTCC PICtail Plus Daughter Board ( AC164140 )

      MCP79410

      The MCP7941X RTCC PICtail™ Plus Daughter Board demonstrates the features and abilities of the MCP7941X and MCP7940X I²C™ Real-Time Clock/Calendar family in standard development platforms. By designing this daughter board with the PICtail Plus, PICtail and PICkit™ serial connectors, it will operate with the Explorer 16 Development Board, the PICDEM PIC18 Explorer Board, the...

    Similar Devices
    Product
    Price5K
    $0.66
    $0.72
    $0.72
    $0.46
    $0.59
    $0.72
    $0.78
    $0.78
    $0.90
    $0.96
    $0.96
    $0.96
    $1.02
    $1.02
    $1.22
    $1.28
    $1.28
    $1.28
    $1.34
    $1.34
    RoHS Information
    Part
    Number
    Device
    Weight
    Shipping
    Weight
    Lead
    Count
    Package
    Type
    Package
    Width
    Solder
    Composition
    JEDEC
    Indicator
    RoHS
     
    China
    EFUP
    MCP7940N-I/P
    0.486700
    0.900000
    8
    PDIP
    .300in
    Matte Tin
    e3
    MCP7940N-E/SN
    0.078000
    0.160000
    8
    SOIC
    .150In(3.90mm)
    Matte Tin
    e3
    MCP7940NT-E/SN
    0.078000
    0.230303
    8
    SOIC
    .150In(3.90mm)
    Matte Tin
    e3
    MCP7940N-I/SN
    0.078000
    0.160000
    8
    SOIC
    .150In(3.90mm)
    Matte Tin
    e3
    MCP7940NT-I/SN
    0.078000
    0.230303
    8
    SOIC
    .150In(3.90mm)
    Matte Tin
    e3
    MCP7940N-I/ST
    0.033000
    0.090000
    8
    TSSOP
    4.4mm
    Matte Tin
    e3
    MCP7940NT-I/ST
    0.033000
    0.215600
    8
    TSSOP
    4.4mm
    Matte Tin
    e3
    MCP7940N-I/MS
    0.025600
    0.070000
    8
    MSOP
    3x3mm
    Matte Tin
    e3
    MCP7940NT-I/MS
    0.025600
    0.215600
    8
    MSOP
    3x3mm
    Matte Tin
    e3
    MCP7940N-E/MS
    0.025600
    0.070000
    8
    MSOP
    3x3mm
    Matte Tin
    e3
    MCP7940NT-E/MS
    0.025600
    0.215600
    8
    MSOP
    3x3mm
    Matte Tin
    e3
    MCP7940NT-I/MNY
    0.014300
    0.248485
    8
    TDFN
    2x3x0.8mm
    NiPdAu
    e4
    To see a complete listing of RoHS data for this device, please Click here
    Shipping Weight = Device Weight + Packing Material weight. Please contact sales office if device weight is not available.