MCP79510T-I/MS

Real Time Clock Overview

The MCP79510T-I/MS is a battery-backed SPI Real-Time Clock/Calendar (RTCC) from Microchip Technology. It tracks time using internal counters for hours, minutes, seconds, hundredths of seconds, day of week, date, month, and year, with leap year compensation to 2399. The device operates on a primary supply of 1.8V to 3.6V and supports backup voltage from 1.3V to 3.6V. Typical timekeeping current is 1.2 µA at 3.0V from VCC and 1.0 µA at 3.0V from VBAT. It features 64 bytes of battery-backed SRAM and 1 Kbit of EEPROM. Communication is handled via an SPI interface with a clock rate up to 5 MHz.

Real Time Clock Feature Summary

• Real-Time Clock/Calendar with dual programmable alarms and power-fail timestamp logging
• On-chip digital trimming for ±259 ppm range with ±1 ppm resolution
• 64-byte battery-backed SRAM and 1 Kbit EEPROM with software write-protect
• Automatic switchover to battery backup when primary power is lost

Real Time Clock Applications

• Industrial systems requiring accurate timekeeping over wide temperature ranges
• Data logging applications utilizing the power-fail timestamp feature
• Embedded devices needing non-volatile memory for configuration or user data

Real Time Clock Procurement Notes

Verify the specific suffix 'T-I/MS' corresponds to the tape and reel packaging format as indicated by the 'T'. Confirm the industrial temperature grade (-40°C to +85°C) matches the application environment requirements. Ensure the SPI interface compatibility with the host microcontroller is validated against the AC characteristics provided in the datasheet.

Real Time Clock Selection Notes

Select this component if a 1 Kbit EEPROM size is sufficient, distinguishing it from the 2 Kbit EEPROM variant in the MCP7952X series. The MCP79510 lacks the pre-programmed EUI-48/EUI-64 MAC address found in the MCP79511/MCP79521 variants, offering a blank protected EEPROM area instead. Ensure external load capacitors are selected to match the crystal's specified load capacitance of 6-9 pF for optimal oscillator performance.

Real Time Clock Part Context

This part belongs to the MCP795XX family of compact, 10-pin RTCCs. It shares the same pinout and core functionality as the MCP79520 but differs in EEPROM capacity. The 'I' designation indicates the industrial temperature range, while '/MS' specifies the 10-lead MSOP package. The 'T' prefix typically denotes tape and reel packaging for automated assembly.

Real Time Clock Replacement Considerations

The MCP79520T-I/MS serves as a direct functional substitute with increased 2 Kbit EEPROM storage. For applications requiring unique identification, the MCP79511T-I/MS provides pre-programmed EUI-48 addresses. Cross-referencing should confirm that the additional memory or ID features do not introduce incompatibilities with existing firmware.