MCP795W11-I/ST

Real Time Clock Overview

The MCP795W11-I/ST is a battery-backed SPI Real-Time Clock/Calendar manufactured by Microchip Technology. It operates within an industrial temperature range of -40°C to +85°C and supports a supply voltage of 1.8V to 3.6V. The device features a 1 Kbit EEPROM, 64 bytes of SRAM, and a 128-bit protected EEPROM area preprogrammed with an EUI-48 MAC address. Timekeeping includes hundredths of seconds, leap year compensation to 2399, and dual programmable alarms. It utilizes a 32.768 kHz crystal oscillator with on-chip digital trimming for ±1 ppm resolution.

Real Time Clock Feature Summary

• Integrated RTCC with 12/24-hour modes and leap year compensation to 2399
• 1 Kbit EEPROM and 64-byte battery-backed SRAM
• 128-bit protected EEPROM containing factory-programmed EUI-48™ MAC address
• Dual Event Detect Modules (High-Speed and Low-Speed) and Programmable Watchdog Timer

Real Time Clock Applications

• Systems requiring precise timekeeping with low-power backup capabilities
• Applications needing unique hardware identification via preprogrammed EUI-48 addresses
• Industrial environments requiring robust event detection and watchdog functionality

Real Time Clock Procurement Notes

Verify the specific ordering suffix 'I/ST' corresponds to the Industrial temperature grade (-40°C to +85°C) and TSSOP-14 package. Confirm that the EUI-48™ MAC address requirement aligns with the '11' variant in the selection table. Ensure primary power is applied before VBAT to prevent data corruption during switchover.

Real Time Clock Selection Notes

Select the MCP795W11-I/ST when a 1 Kbit EEPROM size is sufficient compared to the 2 Kbit option found in the MCP795W2X series. The '11' designation specifically provides the EUI-48™ protected memory block. For applications requiring EUI-64™ addresses, the MCP795W12 variant must be selected instead.

Real Time Clock Part Context

This component belongs to the MCP795WXX family of battery-backed SPI RTCCs. It shares functional similarities with the MCP795BXX series but differs in boot-up capabilities and specific feature sets. The 'W' prefix denotes the standard feature set including the Watchdog Timer and Event Detect modules.

Real Time Clock Replacement Considerations

The MCP795W21-I/ST serves as a direct pin-compatible alternative offering 2 Kbit EEPROM while retaining the EUI-48™ protected area. Other family members like the MCP795W10 lack the protected EEPROM block.