DS12CR887-33+

Real Time Clock Overview

The DS12CR887-33+ is a real-time clock (RTC) and calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It operates within a supply voltage range of 2.97V to 3.63V and supports an industrial temperature range of -40°C to +85°C. The device features a multiplexed parallel interface compatible with Intel and Motorola bus timing standards. It provides 114 bytes of battery-backed static RAM, leap-year compensation through the year 2100, and automatic power-fail detection with switching to backup power. The component is housed in a 24-pin EDIP module package.

Real Time Clock Feature Summary

• Integrated constant-voltage trickle charger for rechargeable batteries or super capacitors
• Multiplexed byte-wide parallel interface supporting Intel and Motorola modes
• 114 bytes of general-purpose nonvolatile RAM with clear input
• Automatic date adjustment for months with fewer than 31 days and leap years

Real Time Clock Applications

• Embedded systems
• Utility meters
• Security systems
• Network hubs, bridges, and routers

Real Time Clock Procurement Notes

Verify that the specific ordering suffix '-33+' corresponds to the 3.3V operating voltage variant (-33) and lead-free/RoHS compliance (+). Confirm the package type is the 24-pin EDIP module which integrates the crystal and battery. Ensure the application design accounts for the -40°C to +85°C industrial temperature rating.

Real Time Clock Selection Notes

Select this model when a 3.3V logic interface is required instead of the standard 5V variant. The integrated battery and crystal in the EDIP package simplify board layout compared to discrete components. Consider the trickle charger capability if using external rechargeable backup sources, noting that the internal charger on the DS12CR887 variant may be disabled depending on the specific die integration as per the datasheet description.

Real Time Clock Part Context

This part belongs to the DS12R885/DS12CR887/DS12R887 family of RTCs with constant-voltage trickle chargers. The DS12CR887 specifically encapsulates the DS12R885 die with a crystal and battery in an EDIP module. The '-33' suffix denotes the 3.3V operation range, while '+' indicates RoHS compliance. It serves as a drop-in replacement for older RTCs like the DS12885.

Real Time Clock Replacement Considerations

Public confirmed substitute part numbers include DS12R885-33+, DS12CR887-5+, and DS12R887-33. Verify pin compatibility and voltage levels when substituting between the 5V and 3.3V variants.