DS1558Y+TRL

Real Time Clock Overview

The DS1558Y+TRL is a real-time clock (RTC) and non-volatile RAM controller in a 48-pin TQFP package. It operates at 5V with a temperature range of -40°C to +85°C. The device integrates an RTC, watchdog timer, power-fail control, and NV SRAM management. RTC registers are mapped to the top 16 locations of the external SRAM address space, accessed via parallel interface. It features BCD-coded timekeeping with automatic leap-year compensation up to 2100, battery voltage monitoring, and programmable alarm/wake-up functions.

Real Time Clock Feature Summary

• Integrated RTC, watchdog timer, and NV SRAM controller with parallel interface
• BCD-coded calendar/clock with automatic leap-year compensation valid to 2100
• Power-fail write protection and seamless switchover to backup battery
• Programmable alarm and watchdog timer with interrupt output

Real Time Clock Applications

• Systems requiring precise timekeeping with data retention during power loss
• Embedded controllers needing integrated watchdog and reset management
• Industrial equipment operating in extended temperature environments

Real Time Clock Procurement Notes

Verify the specific revision level against current datasheets for any errata. Confirm that the TRL suffix indicates tape-and-reel packaging if required by assembly processes. Ensure compatibility with 5V logic levels and check for lead-free compliance markings on the component top mark.

Real Time Clock Selection Notes

Select this model for applications requiring a 5V supply and parallel SRAM interface. The DS1558W variant is suitable for 3.3V systems. Ensure the design accommodates the 48-pin TQFP footprint and provides appropriate decoupling for the VCC and VBAT pins to maintain stable operation.

Real Time Clock Part Context

This component belongs to the DS1558 family of watchdog clocks with NV RAM control. It combines timing, memory management, and system supervision into a single IC, reducing board space compared to discrete solutions. The Y suffix denotes the 5V operating voltage version.

Real Time Clock Replacement Considerations

DS1558Y+ serves as a direct functional replacement for earlier DS1558Y revisions. For 3.3V applications, consider the DS1558W+ series. Verify pinout compatibility when substituting with other RTC/SRAM controller combinations.