Equivalent & Substitute Parts for DS1678S/T&R

Part Overview

The DS1678S/T&R is a Real Time Clock (RTC) IC Time Event Recorder manufactured by Analog Devices Inc./Maxim Integrated. This 8-SOIC surface mount device provides 32-byte I2C/2-Wire Serial interface functionality with integrated alarm, leap year, NVSRAM, and Y2K features. The DS1678S/T&R is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Substitute components must maintain functional compatibility across timing, interface, and electrical specifications while accommodating packaging and compliance differences.

Substiute Parts

DS1678S/T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 1157DS1678S/T&R Datasheet

Current PartRFQ

DS1678S+T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 3299DS1678S+T&R Datasheet

DirectRFQ

RX-8035LC:B PURE SN

EPSONIn Stock: 1021RX-8035LC:B PURE SN Datasheet

MFR RecommendedRFQ

RX-8035LCB0 PURE SN

EPSONIn Stock: 996RX-8035LCB0 PURE SN Datasheet

MFR RecommendedRFQ

RX-8035SA:AC3 PURE SN

EPSONIn Stock: 1010RX-8035SA:AC3 PURE SN Datasheet

MFR RecommendedRFQ

RX8130CE B0

EPSONIn Stock: 8065RX8130CE B0 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the DS1678S/T&R are selected based on the following critical parameters:

Functional Compatibility:

• Real Time Clock (RTC) Time Event Recorder type
• I2C/2-Wire Serial interface protocol
• Operating temperature range: -40°C ~ 85°C
• Time format support: HH:MM:SS (12/24 hr)
• Date format support: YY-MM-DD-dd
• Alarm feature availability

Electrical Compatibility:

• Supply voltage range overlap or compatibility
• Battery backup voltage support
• Timekeeping current specifications

Physical & Compliance Considerations:

• Surface mount technology
• RoHS3 compliance (preferred for new designs)
• Moisture sensitivity level MSL 1 (Unlimited)

Substitute parts may differ in package configuration (8-SOIC, 12-TFSOJ, 14-SOIC, 10-SMD), memory size, and specific voltage ranges while maintaining core RTC functionality and interface protocol.

Parameter Comparison

Engineering Selection Recommendations

DS1678S+T&R (Direct Successor) This part represents the direct active replacement for the obsolete DS1678S/T&R. It maintains identical electrical specifications, memory size (32B), time/date formats, and 8-SOIC packaging. The DS1678S+T&R achieves ROHS3 compliance, making it the preferred choice for new designs requiring the original form factor and functional equivalence. Inventory availability (3200 pcs) supports production requirements.

EPSON RX-8035 Series (RX-8035LC:B, RX-8035LCB0, RX-8035SA:AC3) The EPSON RX-8035 series provides functional RTC capability with I2C interface, time format support (HH:MM:SS 12/24 hr), and date format support (YY-MM-DD-dd). These parts offer extended supply voltage ranges (2.4V ~ 5.5V) and broader battery voltage support (1V ~ 5.5V) compared to the DS1678S/T&R. Package options include 12-TFSOJ and 14-SOIC configurations. All variants are ROHS3 compliant and actively produced. Selection between RX-8035LC:B (Strip packaging) and RX-8035LCB0 (Tape & Reel) depends on procurement and assembly requirements.

EPSON RX8130CE B0 (Ultra-Low Power Alternative) The RX8130CE B0 offers the lowest timekeeping current specification (0.5µA @ 3V) and widest supply voltage range (1.25V ~ 5.5V). This 10-SMD package variant is suitable for battery-powered applications requiring extended operational life. ROHS3 compliance and high inventory availability (8010 pcs) support volume production. Note that specific time and date format specifications are not provided for this variant.

Frequently Asked Questions (FAQ)

Q: Can DS1678S+T&R directly replace DS1678S/T&R in existing designs? A: Yes. DS1678S+T&R maintains identical electrical specifications, memory size, time/date formats, interface protocol, and 8-SOIC packaging. The primary difference is product status (Active vs. Obsolete) and RoHS compliance improvement (ROHS3). No design modifications are required.

Q: What are the key differences between EPSON RX-8035 variants? A: RX-8035LC:B, RX-8035LCB0, and RX-8035SA:AC3 share identical electrical specifications and RTC functionality. Differences are packaging (12-TFSOJ vs. 14-SOIC) and procurement format (Strip vs. Tape & Reel). RX-8035LC:B and RX-8035LCB0 are functionally equivalent; selection depends on assembly process requirements.

Q: Is package change from 8-SOIC to 12-TFSOJ or 14-SOIC acceptable? A: Package changes require PCB layout redesign and assembly process validation. While electrical functionality remains compatible, physical footprint, pin count, and thermal characteristics differ. Engineering review and prototype testing are necessary before production implementation.

Q: What is the advantage of RX8130CE B0 over other substitutes? A: RX8130CE B0 provides the lowest timekeeping current (0.5µA @ 3V) and widest supply voltage range (1.25V ~ 5.5V), making it optimal for battery-powered or ultra-low-power applications. The 10-SMD package offers a compact form factor. Trade-off is the 10-pin configuration versus 8-pin or 12-pin alternatives.

Q: Are all substitute parts ROHS3 compliant? A: Yes. All active substitute parts (DS1678S+T&R, RX-8035LC:B, RX-8035LCB0, RX-8035SA:AC3, RX8130CE B0) are ROHS3 compliant. The original DS1678S/T&R is RoHS non-compliant, which is one reason substitution is necessary for new designs.

Q: What interface protocol compatibility must be maintained? A: All substitute parts support I2C and/or 2-Wire Serial interface protocols. Designs using I2C protocol are compatible with all listed substitutes. Verify specific protocol requirements in application firmware before selection.

Q: How do battery voltage ranges affect substitute selection? A: DS1678S/T&R supports 2.6V ~ 4.6V battery voltage. EPSON RX-8035 series supports 1V ~ 5.5V, offering greater flexibility for various battery types and configurations. RX8130CE B0 does not specify battery voltage support. Select based on backup power architecture requirements.