DS17487-3 Equivalent & Substitute Parts

Part Overview

The DS17487-3 is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This device provides 4KB of parallel-accessible memory with alarm, daylight savings, leap year, and non-volatile SRAM (NVSRAM) capabilities. The part is currently classified as obsolete, making equivalent and substitute parts necessary for ongoing system support and new design implementations. The DS17487-3 operates in the 2.7V to 3.7V supply range with through-hole 24-DIP packaging.

Substiute Parts

DS17487-3

Analog Devices Inc./Maxim IntegratedIn Stock: 2186DS17487-3 Datasheet

Current PartRFQ

DS17487-3+

Analog Devices Inc./Maxim IntegratedIn Stock: 1192DS17487-3+ Datasheet

DirectRFQ

BQ4802YDW

BenchmarqIn Stock: 1824BQ4802YDW Datasheet

MFR RecommendedRFQ

M48T08-100PC1

STMicroelectronicsIn Stock: 1683M48T08-100PC1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the DS17487-3 is determined by the following critical parameters: parallel interface architecture, clock/calendar functionality with alarm capability, 4KB memory capacity, low-voltage operation (2.7V ~ 3.7V supply range), through-hole DIP packaging, and support for 12/24-hour time format with YY-MM-DD-dd date format.

Two substitute categories exist:

Direct Equivalent (Same Electrical & Mechanical Specifications): DS17487-3+ maintains identical electrical characteristics, memory size, interface type, voltage ranges, and DIP packaging. This part differs only in product status (active vs. obsolete) and RoHS compliance (ROHS3 compliant vs. non-compliant).

Functional Equivalent (Different Package & Voltage Requirements): M48T08-100PC1 and BQ4802YDW provide clock/calendar functionality with parallel interface and alarm/calendar features. However, these parts operate at different supply voltages (4.75V ~ 5.5V for M48T08-100PC1 and 4.5V ~ 5.5V for BQ4802YDW), use different package types (28-DIP and 28-SOIC respectively), and have different memory configurations. These substitutes require circuit redesign to accommodate voltage and package differences.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (No Circuit Modification Required):

DS17487-3+ is the appropriate choice when pin-for-pin compatibility and identical electrical operation are required. This part maintains the same 2.7V ~ 3.7V supply voltage, 24-DIP through-hole package, 4KB memory, and parallel interface as the original DS17487-3. The primary advantage is active product status and ROHS3 compliance, eliminating obsolescence risk and supporting modern supply chain requirements.

For Functional Substitution (Circuit Redesign Required):

M48T08-100PC1 and BQ4802YDW provide clock/calendar functionality with parallel interface but require circuit modifications. M48T08-100PC1 operates at 4.75V ~ 5.5V and uses 28-DIP packaging, necessitating voltage regulation changes and PCB layout modifications. BQ4802YDW operates at 4.5V ~ 5.5V in 28-SOIC surface-mount packaging, requiring both voltage and assembly process changes. These substitutes are suitable only when system redesign is feasible and the higher supply voltage requirement can be accommodated.

Frequently Asked Questions (FAQ)

Q: Can DS17487-3+ be used as a direct drop-in replacement for DS17487-3?

A: Yes. DS17487-3+ maintains identical electrical specifications, memory capacity, interface type, voltage ranges, and DIP packaging. No circuit modifications are required for direct substitution.

Q: What are the key differences between DS17487-3 and M48T08-100PC1?

A: The primary differences are supply voltage (2.7V ~ 3.7V vs. 4.75V ~ 5.5V), package type (24-DIP vs. 28-DIP), and time format support (12/24 hr vs. 24 hr only). M48T08-100PC1 requires voltage regulation circuit changes and PCB layout modifications.

Q: Is BQ4802YDW compatible with existing DS17487-3 designs?

A: BQ4802YDW is not a direct replacement. It requires different supply voltage (4.5V ~ 5.5V), uses surface-mount 28-SOIC packaging instead of through-hole 24-DIP, and necessitates complete circuit redesign and assembly process changes.

Q: What is the impact of RoHS compliance on part selection?

A: DS17487-3 is RoHS non-compliant, while DS17487-3+ is ROHS3 compliant. For new designs or systems requiring RoHS compliance, DS17487-3+ is the appropriate choice. Existing systems using DS17487-3 may continue operation without modification.

Q: Can M48T08-100PC1 operate in 12-hour time format like DS17487-3?

A: No. M48T08-100PC1 supports 24-hour time format only, while DS17487-3 supports both 12-hour and 24-hour formats. This functional difference may impact software compatibility.

Q: What are the packaging considerations for each substitute?

A: DS17487-3 and DS17487-3+ use identical 24-DIP through-hole packaging. M48T08-100PC1 uses 28-DIP through-hole packaging with different pin count and spacing. BQ4802YDW uses 28-SOIC surface-mount packaging, requiring different PCB footprints and assembly methods.