DS1691 Equivalent & Substitute Parts Reference

Part Overview

The DS1691 is a Real Time Clock (RTC) IC with Clock/Calendar functionality manufactured by Analog Devices Inc./Maxim Integrated. This component provides 114 bytes of memory with parallel interface, supporting both 12/24-hour time formats and YY-MM-DD date formats. The DS1691 is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Substitute parts must maintain functional compatibility across core timing, memory, and interface specifications while accommodating different packaging and mounting technologies.

Substiute Parts

DS1691

Analog Devices Inc./Maxim IntegratedIn Stock: 1291DS1691 Datasheet

Current PartRFQ

BQ4802LYPW

Texas InstrumentsIn Stock: 9564BQ4802LYPW Datasheet

MFR RecommendedRFQ

M48T02-70PC1

STMicroelectronicsIn Stock: 1276M48T02-70PC1 Datasheet

MFR RecommendedRFQ

M48T08Y-10MH1F

STMicroelectronicsIn Stock: 1165M48T08Y-10MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DS1691 is determined by the following critical parameters:

Core Functional Requirements:

• Clock/Calendar type with parallel interface
• Time format support (12/24-hour capability preferred)
• Date format support (YY-MM-DD or extended formats)
• Operating temperature range: 0°C ~ 70°C minimum
• Voltage supply compatibility with 2.7V ~ 5.5V range

Packaging & Mounting Considerations:

• Through-hole mounting preferred for direct replacement
• Surface-mount alternatives acceptable with design modification
• Pin count and footprint compatibility requirements

Compliance & Status:

• Active product status preferred for long-term availability
• RoHS compliance status noted for regulatory requirements

The three substitute parts listed (BQ4802LYPW, M48T02-70PC1, M48T08Y-10MH1F) meet core functional requirements but differ in packaging, mounting technology, and voltage specifications. Selection depends on application requirements and PCB design constraints.

Parameter Comparison

Engineering Selection Recommendations

BQ4802LYPW (Texas Instruments): This substitute is suitable for new designs requiring surface-mount technology. The part operates within the 2.7V ~ 3.6V range, making it compatible with low-voltage applications. ROHS3 compliance and active product status ensure long-term availability and regulatory alignment. The 28-TSSOP package requires PCB redesign but offers reduced board space. Additional features including daylight savings, supervisor, and watchdog timer functionality provide enhanced capability beyond the original DS1691.

M48T02-70PC1 (STMicroelectronics): This substitute maintains through-hole mounting compatibility with the DS1691, simplifying direct replacement in existing designs. The 24-DIP package differs from the original 28-DIP, requiring pin mapping verification. Voltage supply range is limited to 4.75V ~ 5.5V, restricting use to 5V systems only. ROHS3 compliance and active product status support regulatory requirements and supply chain continuity. Suitable for applications where through-hole mounting is mandatory and 5V operation is acceptable.

M48T08Y-10MH1F (STMicroelectronics): This substitute provides surface-mount technology with 28-pin configuration matching the DS1691 pin count. Voltage supply range of 4.5V ~ 5.5V accommodates standard 5V systems. ROHS3 compliance and active product status ensure regulatory alignment and availability. The 28-SOP package with SNAPHAT Sockets enables socket-based implementation, reducing soldering requirements. Watchdog timer functionality adds system supervision capability. Suitable for new designs prioritizing surface-mount assembly and enhanced reliability features.

Frequently Asked Questions (FAQ)

Q: Can the BQ4802LYPW directly replace the DS1691 without PCB modification?

A: No. The BQ4802LYPW uses 28-TSSOP surface-mount packaging versus the DS1691's 28-DIP through-hole package. PCB redesign is required to accommodate the different footprint and mounting technology.

Q: What is the primary difference between M48T02-70PC1 and M48T08Y-10MH1F?

A: M48T02-70PC1 uses 24-DIP through-hole mounting with 4.75V ~ 5.5V supply range. M48T08Y-10MH1F uses 28-SOP surface-mount with 4.5V ~ 5.5V supply range and includes watchdog timer functionality. Pin count and mounting technology differ significantly.

Q: Is the DS1691 compatible with 3.3V systems?

A: The DS1691 supports 2.7V ~ 3.3V operation. Among the substitutes, only BQ4802LYPW supports 3.3V operation (2.7V ~ 3.6V range). M48T02-70PC1 and M48T08Y-10MH1F require 4.5V minimum and are unsuitable for 3.3V applications.

Q: Which substitute offers the best long-term availability?

A: All three substitutes have active product status from established manufacturers (Texas Instruments and STMicroelectronics), ensuring long-term availability. ROHS3 compliance across all substitutes supports regulatory requirements for new designs.

Q: Does the M48T02-70PC1 have the same pin count as the DS1691?

A: No. The DS1691 is a 28-pin DIP package, while M48T02-70PC1 is a 24-pin DIP package. Pin mapping and functionality verification is required before implementation.

Q: What additional features do the substitutes provide compared to the DS1691?

A: BQ4802LYPW adds daylight savings, supervisor, and watchdog timer functions. M48T08Y-10MH1F includes watchdog timer capability. M48T02-70PC1 provides only leap year functionality matching the original specification.