DS1500WEN

Real Time Clock Overview

The DS1500WEN is a Y2K-compliant real-time clock (RTC) integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It features a byte-wide parallel interface, 256 bytes of nonvolatile SRAM, and automatic leap-year compensation valid through the year 2100. The device operates within an industrial temperature range of -40°C to +85°C at a supply voltage of 3.0V to 3.6V. Key specifications include a maximum standby current of 4mA at 3.3V, a battery input range of 2.5V to 3.7V, and a 32.768kHz square-wave output. It integrates programmable watchdog timers, alarms, power-on reset, and external SRAM backup control.

Real Time Clock Feature Summary

• Y2K-compliant RTC with BCD-coded registers for century, year, month, date, day, hours, minutes, and seconds.
• Includes 256 bytes of onboard nonvolatile SRAM and NV control for backing up external SRAM.
• Features programmable watchdog timer, time-of-day alarm, and precision power-on reset.
• Supports auxiliary battery input (VBAUX) for kickstart and square-wave output functions during main power loss.

Real Time Clock Applications

• Remote Systems
• Battery-Backed Systems
• Telecom Switches
• Office Equipment
• Consumer Electronics

Real Time Clock Procurement Notes

Verify that the specific part number matches the industrial temperature grade (-40°C to +85°C) and the 3.3V operating voltage requirement. Confirm package compatibility with the 32-pin TSOP form factor. Check for lead-free/RoHS compliance status indicated by the '+' suffix in ordering information.

Real Time Clock Selection Notes

Select this component when a parallel interface is required for high-speed register access compared to serial alternatives. Ensure the system design accommodates the 3.3V logic levels and provides separate VBAT and VBAUX connections if auxiliary battery features are utilized. Verify crystal load capacitance requirements (6pF or 12.5pF) match the selected oscillator.

Real Time Clock Part Context

The DS1500 series includes variants differentiated by operating voltage and temperature range. The 'W' suffix denotes 3.3V operation, while 'Y' denotes 5.0V operation. The 'E' suffix indicates an extended industrial temperature range (-40°C to +85°C), whereas the absence of 'E' typically implies commercial range (0°C to +70°C). This specific model combines the 3.3V voltage profile with the industrial temperature rating.

Real Time Clock Replacement Considerations

Direct pin-compatible substitutes within the same family include DS1500WE+ (commercial temperature) and DS1500YE+ / DS1500YEN+ (5.0V operation). Note that voltage and temperature ranges differ between these options; verify electrical specifications before substitution.