MICROCHIP MCP7940M-I/MS

The MCP7940M Real-Time Clock/Calendar (RTCC) tracks time using internal counters for hours, minutes, seconds, days, months, years, and day of week. Alarms can be configured on all counters up to and including months. For usage and configuration, the MCP7940M supports I²C communications up to 400 kHz. The open-drain, multi-functional output can be configured to assert on an alarm match, to output a selectable frequency square wave, or as a general purpose output. The MCP7940M is designed to operate using a 32.768 kHz tuning fork crystal with external crystal load capacitors. On-chip digital trimming can be used to adjust for frequency variance caused by crystal tolerance and temperature.

• Real-Time Clock/Calendar (RTCC):
  • Hours, Minutes, Seconds, Day of Week, Day, Month, Year
  • Leap year compensated to 2399
  • 12/24 hour modes
• Oscillator for 32.768 kHz Crystals:
  • Optimized for 6 - 9 pF crystals
• 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
• Wide Voltage Range:
  • Operating voltage range of 1.8V to 5.5V
• Low Typical Timekeeping Current:
  • Operating from VCC: 1.2 μA at 3.3V
• 64-byte SRAM
• 2-Wire Serial Interface, I²C Compatible
  • I²C clock rate up to 400 kHz
• Temperature Range:
  • Industrial (I): -40°C to +85°C
• 8-Lead SOIC, MSOP, TSSOP, PDIP and 2x3 TDFN