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MCP7940M

I2C Real-Time Clock/Calendar with SRAM

Status: In Production

Features:

  • Hours, Minutes, Seconds, Day of Week, Day, Month, Year
  • Leap year compensated  to 2399
  • 12/24 hour modes
  • 1 PPM Resolution
  • ±129 PPM Range
  • Dual Programmable Alarms
  • Clock output with selectable frequency
  • Alarm output
  • General Purpose output
  • 64 Bytes SRAM
  • I2C Clock Frequency up to 400 kHz
  • Operating Voltage 1.8V to 5.5V
  • Low Typical Timekeeping Current
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Overview
Documents
Development Environment
Similar Devices
RoHS Information
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Device Overview

Summary

The MCP7940M I2CTM compatible real-time clock/calendar (RTCC) includes SRAM and a digital trimming circuit for accuracy which is normally found in higher priced devices. Using a low-cost 32,768 kHz crystal or other clock source, time is tracked in either a 12-hour or 24-hour format with an AM/PM indicator and timing to the second, minute, hour, day of the week, day, month and year. As an interrupt or wakeup signal, a multifunction open drain output can be programmed as an Alarm Out or as a Clock Out that supports 4 selectable frequencies.

Additional Features

    Timekeeping
    • 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
    • 64 Bytes 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
    • Low Typical Timekeeping Current
Parametrics
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 +85

Documents

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Data Sheets

Errata

Supporting Collateral

Code Examples

06/23/2015
61KB
06/24/2015
152KB

Development Environment

  • Code Examples

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RoHS Information

Part Number
Device Weight (g)
Shipping Weight (grams)
Lead Count
Package Type
Package Width
Solder Composition
JEDEC Indicator
RoHS
China EFUP
MCP7940M-I/MS
0.025600
0.070000
8
MSOP
3x3mm
Matte Tin
e3
MCP7940MT-I/MS
0.025600
0.215600
8
MSOP
3x3mm
Matte Tin
e3
MCP7940MT-I/MNY
0.014300
0.248485
8
TDFN
2x3x0.8mm
NiPdAu
e4
MCP7940M-I/ST
0.033000
0.090000
8
TSSOP
4.4mm
Matte Tin
e3
MCP7940MT-I/ST
0.033000
0.215600
8
TSSOP
4.4mm
Matte Tin
e3
MCP7940MT-I/STVAO
0.033000
0.215600
8
TSSOP
4.4mm
Matte Tin
e3
MCP7940M-I/SN
0.078000
0.250000
8
SOIC
.150In(3.90mm)
Matte Tin
e3
MCP7940MT-I/SN
0.078000
0.230303
8
SOIC
.150In(3.90mm)
Matte Tin
e3
MCP7940MT-I/SNVAO
0.078000
0.230303
8
SOIC
.150In(3.90mm)
Matte Tin
e3
MCP7940M-I/SNVAO
0.078000
0.250000
8
SOIC
.150In(3.90mm)
Matte Tin
e3
MCP7940M-I/P
0.486700
0.900000
8
PDIP
.300in
Matte Tin
e3
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.

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