DS14285 Real Time Clock IC - Equivalent & Substitute Parts

Part Overview

The DS14285 is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, 114B of non-volatile static RAM (NVSRAM), and parallel interface. This device operates as a 24-DIP through-hole component with comprehensive timekeeping features including alarm, daylight savings, leap year support, and square wave output. The DS14285 is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing system support.

Substiute Parts

DS14285

Analog Devices Inc./Maxim IntegratedIn Stock: 1957DS14285 Datasheet

Current PartRFQ

DS12885+

Analog Devices Inc./Maxim IntegratedIn Stock: 2073DS12885+ Datasheet

MFR RecommendedRFQ

DS1685-5+

Analog Devices Inc./Maxim IntegratedIn Stock: 1293DS1685-5+ Datasheet

MFR RecommendedRFQ

BQ3285S-SB2

Texas InstrumentsIn Stock: 1987BQ3285S-SB2 Datasheet

MFR RecommendedRFQ

BQ4802YDWR

Texas InstrumentsIn Stock: 1873BQ4802YDWR Datasheet

MFR RecommendedRFQ

M48T37Y-70MH1F

STMicroelectronicsIn Stock: 2256M48T37Y-70MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the DS14285 is determined by the following critical parameters:

Primary Compatibility Criteria:

• Parallel interface operation
• 4.5V ~ 5.5V supply voltage compatibility
• HH:MM:SS (12/24 hr) time format support
• YY-MM-DD-dd date format support
• 0°C ~ 70°C operating temperature range
• Alarm, daylight savings, leap year, and square wave output features

Grouping Logic:

Group 1 - Direct DIP Package Equivalents (Through-Hole, 24-DIP): DS12885+ and DS1685-5+ maintain the 24-DIP through-hole form factor, enabling direct socket replacement without PCB redesign. Both are active products with RoHS3 compliance.

Group 2 - Surface Mount Alternative (24-SOIC): BQ3285S-SB2 provides equivalent functionality in a 24-SOIC surface mount package. This substitution requires PCB layout modification but maintains the same pin count and electrical interface.

Group 3 - Enhanced Feature Variants (Surface Mount, 28-SOIC and 44-BSOP): BQ4802YDWR (28-SOIC) and M48T37Y-70MH1F (44-BSOP) offer extended features including supervisor and watchdog timer functionality. These require PCB redesign due to different package geometries and pin configurations.

Parameter Comparison

Engineering Selection Recommendations

For Direct Socket Replacement (Through-Hole, 24-DIP):

DS12885+ is the primary recommendation for applications requiring minimal PCB modification. This part maintains identical package geometry and pin configuration as the DS14285, supports all required timekeeping features, and carries active product status with RoHS3 compliance. Battery supply voltage range extends to 4V, providing broader operational margin.

DS1685-5+ offers an alternative with increased memory capacity (242B versus 114B) and lower timekeeping current consumption (3mA at 5V versus 15mA for DS12885+). This substitution is suitable when additional non-volatile storage is beneficial and power consumption is a design consideration.

For Surface Mount Conversion (24-SOIC):

BQ3285S-SB2 provides functional equivalence in a compact surface mount package with identical feature set to the DS14285. This substitution requires PCB redesign but maintains the same pin count and electrical interface. RoHS3 compliance and active product status support modern manufacturing requirements.

For Enhanced Feature Requirements (28-SOIC and 44-BSOP):

BQ4802YDWR and M48T37Y-70MH1F introduce supervisor and watchdog timer functionality beyond the DS14285 baseline. These parts require significant PCB redesign due to different package geometries and pin counts. Selection depends on whether enhanced monitoring features justify the design effort.

All substitute parts maintain RoHS3 compliance and active product status, addressing the obsolescence of the original DS14285.

Frequently Asked Questions (FAQ)

Q: Can DS12885+ directly replace DS14285 without PCB modification?

A: Yes. DS12885+ maintains identical 24-DIP through-hole package geometry and pin configuration. No PCB layout changes are required for socket replacement. Electrical interface and timekeeping features are compatible.

Q: What is the primary difference between DS12885+ and DS1685-5+?

A: Memory capacity differs: DS12885+ provides 114B (matching DS14285), while DS1685-5+ offers 242B. DS1685-5+ also consumes less current during timekeeping operation (3mA at 5V versus 15mA). Both maintain 24-DIP through-hole packaging and are direct socket replacements.

Q: Why would I select a surface mount package like BQ3285S-SB2?

A: Surface mount packages reduce PCB footprint and support automated assembly processes. BQ3285S-SB2 maintains functional equivalence in 24-SOIC form factor. This substitution requires PCB redesign but is appropriate for new designs prioritizing compact layouts.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts carry RoHS3 compliance status. The original DS14285 is RoHS non-compliant. Substitution with any listed part addresses RoHS compliance requirements for modern manufacturing and distribution.

Q: What is the significance of product status (Active vs. Obsolete)?

A: Active product status ensures ongoing availability, manufacturing support, and supply chain reliability. The DS14285 is obsolete, creating supply risk and potential discontinuation. All substitute parts maintain active status, supporting long-term design viability.

Q: Does M48T37Y-70MH1F require special handling due to its 44-BSOP package?

A: M48T37Y-70MH1F requires SNAPHAT socket accommodation due to its 44-BSOP package geometry. This substitution demands significant PCB redesign and is appropriate only when enhanced features (supervisor, watchdog timer) justify the engineering effort.

Q: Can I use BQ4802YDWR as a direct replacement?

A: No. BQ4802YDWR uses 28-SOIC packaging with different pin configuration and count compared to DS14285. This substitution requires PCB redesign. Selection is appropriate when supervisor and watchdog timer features are required.

Q: What battery voltage range should I design for when selecting a substitute?

A: All substitute parts support battery operation within 2.4V to 4V range. Design systems to accommodate this range. M48T37Y-70MH1F does not specify battery supply voltage, limiting its applicability in battery-backed timekeeping applications.