DS1500W Equivalent & Substitute Parts

Part Overview

The DS1500W is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This 32-DIP through-hole module provides 256 bytes of parallel interface memory with comprehensive timekeeping features including alarm, leap year compensation, non-volatile SRAM, square wave output, and watchdog timer capabilities. The DS1500W is classified as obsolete, making equivalent substitute parts necessary for new designs, maintenance, and legacy system replacements where through-hole packaging and parallel interface requirements persist.

Substiute Parts

DS1500W

Analog Devices Inc./Maxim IntegratedIn Stock: 1178DS1500W Datasheet

Current PartRFQ

DP8573AV/NOPB

Texas InstrumentsIn Stock: 4247DP8573AV/NOPB Datasheet

MFR RecommendedRFQ

M48T08-100PC1

STMicroelectronicsIn Stock: 1683M48T08-100PC1 Datasheet

MFR RecommendedRFQ

M48T58-70PC1

STMicroelectronicsIn Stock: 1546M48T58-70PC1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DS1500W is determined by the following critical parameters:

Primary Substitution Criteria:

• Parallel interface requirement (eliminates serial-only alternatives)
• Through-hole mounting type (eliminates surface mount only options)
• Clock/Calendar functionality with date and time tracking
• 24-hour time format support
• YY-MM-DD-dd date format compatibility

Secondary Compatibility Factors:

• Supply voltage range compatibility or tolerance
• Operating temperature range overlap
• Package footprint and pin count alignment
• Feature set (alarm, leap year, watchdog timer)
• RoHS and regulatory compliance status

The substitute parts identified (DP8573AV/NOPB, M48T08-100PC1, M48T58-70PC1) meet the core functional requirements of parallel-interface RTC Clock/Calendar operation. However, each presents distinct trade-offs in packaging, voltage specifications, and compliance status that must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

M48T08-100PC1 and M48T58-70PC1 (STMicroelectronics Timekeeper® Series)

These parts represent the most direct substitutes for through-hole applications. Both maintain 28-DIP through-hole packaging with 0.600" (15.24mm) module dimensions, compatible with existing PCB layouts designed for the DS1500W. Both are active products with ROHS3 compliance and unlimited moisture sensitivity level (MSL 1), supporting modern manufacturing and environmental standards. Operating temperature range (0°C ~ 70°C) matches the DS1500W specification. Supply voltage requirements (4.75V ~ 5.5V) differ from the DS1500W (3V ~ 3.6V), necessitating power supply circuit modifications. Current consumption during timekeeping (3mA) is lower than the DS1500W (4mA). M48T08-100PC1 includes watchdog timer functionality; M48T58-70PC1 provides leap year support. Both support 24-hour time format and YY-MM-DD-dd date format.

DP8573AV/NOPB (Texas Instruments)

This part is an active product with ROHS3 compliance and superior timekeeping current consumption (1µA @ 5V). However, it uses 28-LCC (J-Lead) surface mount packaging, incompatible with through-hole PCB designs. This substitute is applicable only for new designs or complete PCB redesigns. Supply voltage (4.5V ~ 5.5V) and battery voltage range (2.2V ~ 5.1V) differ from the DS1500W. Operating temperature range extends to -40°C ~ 85°C, exceeding the DS1500W specification. Time format supports both 12-hour and 24-hour modes.

Frequently Asked Questions (FAQ)

Q: Can the M48T08-100PC1 or M48T58-70PC1 directly replace the DS1500W without PCB modifications?

A: Both STMicroelectronics parts maintain the same 28-DIP through-hole package footprint as the DS1500W. However, pin count differs (28-pin versus 32-pin), requiring PCB layout verification. Supply voltage requirements (4.75V ~ 5.5V versus 3V ~ 3.6V) necessitate power supply circuit modifications. Pin-to-pin functional mapping must be confirmed against device datasheets before implementation.

Q: Why does the DP8573AV/NOPB have significantly lower timekeeping current consumption?

A: The DP8573AV/NOPB achieves 1µA timekeeping current through advanced semiconductor process technology and design optimization. This represents a generational improvement over the DS1500W (4mA). However, this advantage is offset by surface mount packaging incompatibility with through-hole designs.

Q: What are the key differences between M48T08-100PC1 and M48T58-70PC1?

A: Both parts share identical packaging, voltage, temperature, and current specifications. M48T08-100PC1 includes watchdog timer functionality; M48T58-70PC1 emphasizes leap year support. Feature selection depends on application-specific requirements for system monitoring or calendar accuracy.

Q: Is the DS1500W RoHS non-compliance a barrier to substitution?

A: RoHS compliance status affects manufacturing and environmental regulatory requirements. The substitute parts (M48T08-100PC1, M48T58-70PC1, DP8573AV/NOPB) are all ROHS3 compliant, supporting modern manufacturing standards and environmental directives. Selection of compliant substitutes is recommended for new production and legacy system updates.

Q: Can the DS1500W be used in new designs, or must substitutes be selected?

A: The DS1500W is classified as obsolete. While existing inventory may be available, new designs should incorporate active substitute parts to ensure long-term supply chain stability, manufacturing support, and compliance with current environmental and regulatory standards.

Q: What is the impact of different supply voltage ranges on system design?

A: The DS1500W operates at 3V ~ 3.6V, while all identified substitutes require 4.75V ~ 5.5V (M48T series) or 4.5V ~ 5.5V (DP8573AV/NOPB). Systems designed for 3V operation require power supply redesign or voltage regulation circuits to accommodate substitute parts. Battery backup voltage specifications also differ and must be evaluated for backup power system compatibility.