DS14285S Real Time Clock IC Equivalent & Substitute Parts

Part Overview

The DS14285S is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This device provides parallel interface timekeeping with 114B of NVSRAM, alarm capability, daylight savings support, and leap year compensation. The DS14285S is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing system support.

Substiute Parts

DS14285S

Analog Devices Inc./Maxim IntegratedIn Stock: 1935DS14285S Datasheet

Current PartRFQ

DS1685S-5+

Analog Devices Inc./Maxim IntegratedIn Stock: 1030DS1685S-5+ Datasheet

MFR RecommendedRFQ

BQ4802LYDW

Texas InstrumentsIn Stock: 1993BQ4802LYDW Datasheet

MFR RecommendedRFQ

M48T37Y-70MH1F

STMicroelectronicsIn Stock: 2256M48T37Y-70MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DS14285S is determined by the following critical parameters:

Primary Compatibility Criteria:

• Interface type (Parallel)
• Time and date format support (HH:MM:SS 12/24 hr, YY-MM-DD-dd)
• Operating temperature range (0°C ~ 70°C)
• Supply voltage compatibility (4.5V ~ 5.5V primary, 2.5V ~ 3.6V battery backup)
• Mounting type (Surface Mount)
• Core RTC functionality (Clock/Calendar with alarm capability)

Secondary Considerations:

• Package form factor (24-SOIC preferred for direct replacement)
• Memory capacity (114B minimum)
• Feature set (Alarm, Daylight Savings, Leap Year support)
• Product status and compliance certifications

The three substitute parts listed below meet the functional and electrical requirements for RTC Clock/Calendar applications. Variations in package size, memory capacity, and additional features are noted in the parameter comparison table.

Parameter Comparison

Engineering Selection Recommendations

DS1685S-5+ (Recommended Primary Substitute)

The DS1685S-5+ is the preferred substitute for the DS14285S. Both devices are manufactured by Analog Devices Inc./Maxim Integrated and share identical package geometry (24-SOIC). The DS1685S-5+ is in active product status with ROHS3 compliance, addressing the obsolescence of the DS14285S. The device supports the same parallel interface, time format (12/24 hr), and date format (YY-MM-DD-dd). Memory capacity is increased to 242B. Operating temperature range and supply voltage specifications are identical. The DS1685S-5+ includes Y2K support and maintains pin-compatible functionality for direct board-level replacement.

BQ4802LYDW (Alternative Substitute)

The BQ4802LYDW, manufactured by Texas Instruments, provides active product status and ROHS3 compliance. This device operates at a lower supply voltage range (2.7V ~ 3.6V) compared to the DS14285S (4.5V ~ 5.5V), making it suitable for low-power applications. The package is 28-SOIC, requiring PCB layout modification. The device supports parallel interface, 12/24 hr time format, and YY-MM-DD-dd date format. Additional features include supervisor and watchdog timer functionality. Operating temperature range matches the DS14285S specification.

M48T37Y-70MH1F (Alternative Substitute)

The M48T37Y-70MH1F, manufactured by STMicroelectronics under the Timekeeper® series, is in active product status with ROHS3 compliance. This device operates at the same supply voltage as the DS14285S (4.5V ~ 5.5V) and supports parallel interface with 24 hr time format and YY-MM-DD-dd date format. The package is 44-BSOP, requiring significant PCB layout modification and SNAPHAT connector. Moisture sensitivity level is MSL 3 (168 Hours), requiring controlled storage conditions. This option is suitable for applications where expanded functionality and higher pin count are beneficial.

Frequently Asked Questions (FAQ)

Q: Can the DS1685S-5+ directly replace the DS14285S on existing PCBs?

A: Yes. The DS1685S-5+ shares the identical 24-SOIC package geometry and pin configuration with the DS14285S. Both devices support parallel interface, 12/24 hr time format, and YY-MM-DD-dd date format. Direct board-level replacement is possible without PCB modification.

Q: What are the key differences between the DS14285S and DS1685S-5+?

A: The DS1685S-5+ offers increased memory capacity (242B vs. 114B), active product status (vs. obsolete), ROHS3 compliance (vs. non-compliant), and Y2K support. Timekeeping current consumption increases from 0.5µA to 3mA at 5V. Both devices maintain identical supply voltage ranges and operating temperature specifications.

Q: Is the BQ4802LYDW suitable for 5V systems?

A: No. The BQ4802LYDW operates at 2.7V ~ 3.6V supply voltage, which is incompatible with 5V systems. This device is intended for low-power applications. Use the DS1685S-5+ or M48T37Y-70MH1F for 5V compatibility.

Q: What PCB modifications are required for the BQ4802LYDW?

A: The BQ4802LYDW uses a 28-SOIC package compared to the DS14285S 24-SOIC package. PCB footprint modification is required. Pin count and signal routing differ; schematic review is necessary before implementation.

Q: What is the SNAPHAT requirement for the M48T37Y-70MH1F?

A: The M48T37Y-70MH1F uses a 44-BSOP package that requires a SNAPHAT connector for proper mechanical and electrical interface. This is a specialized packaging requirement not present in the DS14285S or other listed substitutes.

Q: Are all substitute parts RoHS compliant?

A: The DS1685S-5+, BQ4802LYDW, and M48T37Y-70MH1F are all ROHS3 compliant. The original DS14285S is RoHS non-compliant. Compliance with RoHS regulations may be a requirement for new designs or system updates.

Q: What is the moisture sensitivity level (MSL) difference?

A: The DS14285S, DS1685S-5+, and BQ4802LYDW all have MSL 1 (Unlimited), allowing indefinite storage without moisture control. The M48T37Y-70MH1F has MSL 3 (168 Hours), requiring controlled storage conditions and bake-out procedures before soldering if storage exceeds 168 hours.

Q: Can the M48T37Y-70MH1F be used in 5V systems?

A: Yes. The M48T37Y-70MH1F operates at 4.5V ~ 5.5V supply voltage, matching the DS14285S specification. However, the 44-BSOP package and SNAPHAT connector requirement necessitate significant PCB redesign.