DS1302 Real Time Clock IC - Equivalent & Substitute Parts

Part Overview

The DS1302 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 nonvolatile static RAM (NVSRAM), leap year compensation, and a trickle-charger circuit. The DS1302 operates via 3-Wire Serial interface and supports both 12-hour and 24-hour time formats with date tracking.

The DS1302 is classified as obsolete. Equivalent and substitute parts are necessary for new designs, production continuity, and applications requiring active product status with current manufacturer support and compliance certifications.

Substiute Parts

DS1302

Analog Devices Inc./Maxim IntegratedIn Stock: 16367DS1302 Datasheet

Current PartRFQ

DS1302+

Analog Devices Inc./Maxim IntegratedIn Stock: 27034DS1302+ Datasheet

DirectRFQ

RX-4571LC:B PURE SN

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

MFR RecommendedRFQ

RX-4571LC:B3 PURE SN

EPSONIn Stock: 2650RX-4571LC:B3 PURE SN Datasheet

MFR RecommendedRFQ

RX-4571NB:B

EPSONIn Stock: 1162RX-4571NB:B Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DS1302 is determined by the following critical parameters:

Interface Compatibility: All substitute parts maintain 3-Wire Serial interface, ensuring protocol-level compatibility with existing designs.

Functional Features: Substitute parts retain Clock/Calendar functionality with leap year compensation. The DS1302+ maintains identical feature set (Leap Year, NVSRAM, Trickle-Charger). EPSON RX-4571 series parts provide Clock/Calendar with Alarm and Leap Year features.

Voltage Supply Range: The DS1302 operates at 2V ~ 5.5V. The DS1302+ maintains this range. EPSON RX-4571 series parts operate at 1.6V ~ 5.5V, providing extended low-voltage capability.

Current Consumption: Timekeeping current for DS1302 is 0.3µA ~ 1µA @ 2V ~ 5V. DS1302+ matches this specification. EPSON RX-4571 series specifies 0.95µA ~ 1µA @ 3V ~ 5V.

Mounting and Packaging: DS1302 uses Through Hole 8-DIP packaging. DS1302+ provides the same Through Hole 8-DIP form factor. EPSON RX-4571LC:B and RX-4571LC:B3 PURE SN use Surface Mount 12-TFSOJ packaging. EPSON RX-4571NB:B uses Surface Mount 22-LFDFN packaging.

Product Status and Compliance: DS1302+ is Active with ROHS3 compliance. EPSON RX-4571 series parts are Active with ROHS3 compliance and REACH Affected status.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Through Hole Mounting): The DS1302+ is the direct equivalent to the DS1302. Both use 8-DIP Through Hole packaging and maintain identical electrical specifications. The DS1302+ is Active with ROHS3 compliance, addressing the obsolescence and compliance limitations of the original DS1302.

For Surface Mount Designs: The EPSON RX-4571 series provides Clock/Calendar functionality with 3-Wire Serial interface in surface mount packages. RX-4571LC:B3 PURE SN and RX-4571NB:B are both Active with ROHS3 compliance. These parts extend the operating temperature range to -40°C ~ 85°C and support lower supply voltages (1.6V minimum). Package selection between 12-TFSOJ and 22-LFDFN depends on board layout and pin count requirements.

Compliance Considerations: The DS1302 is RoHS non-compliant. All substitute parts (DS1302+, RX-4571LC:B PURE SN, RX-4571LC:B3 PURE SN, RX-4571NB:B) are ROHS3 compliant, meeting current regulatory requirements. EPSON RX-4571 series parts carry REACH Affected status.

Product Availability: DS1302+ provides the highest inventory availability (27,009 pcs) among direct replacements. EPSON RX-4571LC:B3 PURE SN (2,610 pcs) and RX-4571NB:B (1,083 pcs) are available in active production.

Frequently Asked Questions (FAQ)

Q: Can DS1302+ directly replace DS1302 in existing designs? A: Yes. DS1302+ maintains identical 8-DIP Through Hole packaging, voltage supply range (2V ~ 5.5V), timekeeping current specifications (0.3µA ~ 1µA @ 2V ~ 5V), and operating temperature range (0°C ~ 70°C). The 3-Wire Serial interface and Clock/Calendar functionality are identical.

Q: What are the key differences between DS1302+ and EPSON RX-4571 series? A: DS1302+ uses Through Hole 8-DIP packaging; EPSON RX-4571 series uses Surface Mount packages (12-TFSOJ or 22-LFDFN). EPSON parts extend operating temperature to -40°C ~ 85°C and support lower minimum supply voltage (1.6V vs. 2V). Both maintain 3-Wire Serial interface and Clock/Calendar functionality.

Q: Which substitute part should be selected for new designs? A: For Through Hole applications, DS1302+ is the direct replacement. For new Surface Mount designs, EPSON RX-4571LC:B3 PURE SN or RX-4571NB:B are recommended based on package requirements and board layout constraints.

Q: Are all substitute parts RoHS compliant? A: Yes. DS1302+, RX-4571LC:B PURE SN, RX-4571LC:B3 PURE SN, and RX-4571NB:B are all ROHS3 compliant. The original DS1302 is RoHS non-compliant.

Q: What is the difference between RX-4571LC:B and RX-4571LC:B3 PURE SN? A: Both use 12-TFSOJ Surface Mount packaging and maintain identical electrical specifications. RX-4571LC:B3 PURE SN specifies HH:MM:SS (24 hr) time format and YY-MM-DD-dd date format. Packaging differs: RX-4571LC:B is supplied in Strip; RX-4571LC:B3 PURE SN is supplied in Tape & Reel (TR).

Q: Can EPSON RX-4571 parts be used in battery-backed applications? A: EPSON RX-4571 series does not specify battery supply voltage. DS1302 and DS1302+ specify 2V ~ 5.5V battery supply voltage. For battery-backed timekeeping, DS1302+ is the appropriate selection.

Q: What is the impact of different operating temperature ranges? A: DS1302 and DS1302+ operate 0°C ~ 70°C. EPSON RX-4571 series operates -40°C ~ 85°C. Applications requiring extended temperature operation must use EPSON parts.