DS1302S/T&R Equivalent & Substitute Parts

Part Overview

The DS1302S/T&R is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This component provides 31 bytes of non-volatile static RAM (NVSRAM) with a trickle-charger feature, supporting 3-Wire Serial interface communication. The DS1302S/T&R is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and production continuity.

Substiute Parts

DS1302S/T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 996DS1302S/T&R Datasheet

Current PartRFQ

DS1302S+T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 5240DS1302S+T&R Datasheet

DirectRFQ

RX-4571LC:B PURE SN

EPSONIn Stock: 899RX-4571LC:B PURE SN Datasheet

MFR RecommendedRFQ

S-35192A-I8T1U

ABLIC Inc.In Stock: 776S-35192A-I8T1U Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DS1302S/T&R is determined by the following critical parameters:

Primary Compatibility Criteria:

• Interface type: 3-Wire Serial protocol
• Package type: 8-pin surface mount configuration
• Memory architecture: NVSRAM with calendar/clock functionality
• Time and date format support: HH:MM:SS (12/24 hr) and YY-MM-DD-dd
• Supply voltage compatibility: 2V ~ 5.5V operating range
• Timekeeping current specification: ≤1µA maximum

Substitute Parts Identified:

1. DS1302S+T&R (Analog Devices Inc./Maxim Integrated) - Direct manufacturer variant with identical electrical and mechanical specifications. Active product status with ROHS3 compliance.

2. S-35192A-I8T1U (ABLIC Inc.) - Functionally equivalent RTC with 3-Wire Serial interface, 8-pin surface mount package, and compatible time/date format support. Extended operating temperature range (-40°C ~ 85°C) and ROHS3 compliance.

3. RX-4571LC:B PURE SN (EPSON) - Alternative RTC solution with 3-Wire Serial interface and alarm functionality. Package configuration differs (12-TFSOJ vs. 8-SOIC), requiring PCB layout modification. Extended operating temperature range and ROHS3 compliance.

Parameter Comparison

Engineering Selection Recommendations

DS1302S+T&R is the primary substitute for DS1302S/T&R applications. This part maintains identical electrical specifications, package configuration, and functional characteristics while offering active product status and ROHS3 compliance. No design modifications are required for direct substitution.

S-35192A-I8T1U provides functional equivalence with extended operating temperature range (-40°C ~ 85°C) and ROHS3 compliance. The 8-SMD flat lead package is mechanically compatible with 8-SOIC footprints in most PCB designs. Timekeeping current consumption is higher (8µA ~ 14µA) compared to the original specification (0.3µA ~ 1µA), which may impact battery-backed operation duration in low-power applications.

RX-4571LC:B PURE SN offers alternative RTC functionality with integrated alarm capability and extended operating temperature range. The 12-TFSOJ package requires PCB layout modification and footprint redesign. This option is suitable for applications where package size reduction and enhanced temperature performance justify design revision.

All three substitute parts maintain 3-Wire Serial interface compatibility, support identical time and date formats, and provide unlimited moisture sensitivity rating. Selection should prioritize DS1302S+T&R for direct replacement applications, with S-35192A-I8T1U as the secondary option for designs requiring extended temperature operation without PCB modification.

Frequently Asked Questions (FAQ)

Q: Can DS1302S+T&R be used as a direct replacement for DS1302S/T&R?

A: Yes. DS1302S+T&R is electrically and mechanically identical to DS1302S/T&R, with the same 8-SOIC package, 3-Wire Serial interface, supply voltage range (2V ~ 5.5V), and timekeeping current specifications. The primary difference is product status (Active vs. Obsolete) and RoHS compliance (ROHS3 vs. non-compliant). No design changes are required.

Q: What is the impact of using S-35192A-I8T1U instead of DS1302S/T&R?

A: S-35192A-I8T1U maintains 3-Wire Serial interface compatibility and identical time/date format support. The 8-SMD flat lead package is mechanically compatible with standard 8-SOIC footprints. The primary consideration is timekeeping current consumption: S-35192A-I8T1U draws 8µA ~ 14µA compared to DS1302S/T&R's 0.3µA ~ 1µA. This higher current consumption will reduce battery backup duration in applications relying on extended low-power operation.

Q: Why does RX-4571LC:B PURE SN have a different package type?

A: RX-4571LC:B PURE SN uses a 12-TFSOJ package (0.094", 2.40mm Width) compared to the 8-SOIC package of DS1302S/T&R. This package difference requires PCB footprint redesign and layout modification. The 12-pin configuration accommodates additional features such as integrated alarm functionality. This substitute is appropriate only for applications where design revision is acceptable.

Q: Are all substitute parts RoHS compliant?

A: DS1302S/T&R is RoHS non-compliant. DS1302S+T&R, S-35192A-I8T1U, and RX-4571LC:B PURE SN are all ROHS3 compliant. For applications requiring RoHS compliance, any of the three substitute parts are suitable.

Q: What is the operating temperature range difference between the original and substitutes?

A: DS1302S/T&R operates from 0°C ~ 70°C. S-35192A-I8T1U and RX-4571LC:B PURE SN both support extended range operation from -40°C ~ 85°C. DS1302S+T&R maintains the original 0°C ~ 70°C range. Extended temperature operation is available through S-35192A-I8T1U or RX-4571LC:B PURE SN if required by application specifications.

Q: Can the 3-Wire Serial interface be used identically across all substitute parts?

A: Yes. All substitute parts (DS1302S+T&R, S-35192A-I8T1U, and RX-4571LC:B PURE SN) implement 3-Wire Serial interface protocol. Firmware and software interfaces remain compatible without modification.