DS1501WN Real Time Clock IC - Equivalent & Substitute Parts

Part Overview

The DS1501WN is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality manufactured by Analog Devices Inc./Maxim Integrated. This device provides 256 bytes of parallel interface memory with comprehensive timekeeping features including alarm, leap year compensation, non-volatile SRAM, square wave output, and watchdog timer capabilities. The DS1501WN is classified as obsolete product status. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support legacy system maintenance where this component is specified in active applications.

Substiute Parts

DS1501WN

Analog Devices Inc./Maxim IntegratedIn Stock: 3661DS1501WN Datasheet

Current PartRFQ

M48T35AV-10MH1F

STMicroelectronicsIn Stock: 5879M48T35AV-10MH1F Datasheet

MFR RecommendedRFQ

M48T58Y-70PC1

STMicroelectronicsIn Stock: 1732M48T58Y-70PC1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DS1501WN is determined by the following critical parameters:

Primary Compatibility Criteria:

• Interface type: Parallel
• Time format: HH:MM:SS (24 hr)
• Date format: YY-MM-DD-dd
• RTC with Clock/Calendar functionality
• ROHS3 compliance

Secondary Considerations:

• Voltage supply range compatibility
• Operating temperature range
• Mounting type (Through Hole vs. Surface Mount)
• Package form factor
• Product status (Active vs. Obsolete)

The DS1501WN manufacturer list identifies two substitute parts: M48T35AV-10MH1F and M48T58Y-70PC1. These parts maintain core RTC Clock/Calendar functionality with parallel interface and identical time/date formats. However, they differ in mounting technology, voltage specifications, and operating temperature ranges, which must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

M48T58Y-70PC1 (Preferred for Direct Replacement): This substitute maintains the Through Hole mounting type and 28-DIP package form factor identical to the DS1501WN, enabling direct PCB compatibility without layout modifications. Both devices are ROHS3 compliant with MSL rating of 1 (Unlimited). The M48T58Y-70PC1 operates at 4.5V ~ 5.5V supply voltage, which differs from the DS1501WN's 3V ~ 3.6V specification. This voltage difference requires circuit design verification to confirm compatibility with existing power supply architecture. The M48T58Y-70PC1 is Active product status, ensuring ongoing availability and supply chain support.

M48T35AV-10MH1F (Alternative for Surface Mount Applications): This substitute provides active product status and lower timekeeping current consumption (2mA vs. 4mA). However, it requires Surface Mount technology implementation, necessitating PCB redesign and assembly process changes. The M48T35AV-10MH1F operates within the DS1501WN's 3V ~ 3.6V voltage range, providing direct voltage compatibility. The MSL rating of 3 (168 Hours) requires controlled moisture exposure during storage and handling compared to the DS1501WN's unlimited MSL rating. The 28-SOP package with SNAPHAT Sockets differs significantly from the original 28-DIP form factor.

Both substitutes maintain parallel interface, 24-hour time format, and YY-MM-DD-dd date format specifications. Operating temperature ranges for both substitutes (0°C ~ 70°C) are narrower than the DS1501WN (-40°C ~ 85°C), which must be evaluated against application environmental requirements.

Frequently Asked Questions (FAQ)

Q: Can M48T35AV-10MH1F be used as a direct pin-for-pin replacement for DS1501WN?

A: No. While both devices provide parallel interface Clock/Calendar functionality with identical time and date formats, the M48T35AV-10MH1F uses Surface Mount technology (28-SOP package) whereas the DS1501WN uses Through Hole technology (28-DIP package). Direct PCB substitution is not possible without layout redesign and assembly process modification.

Q: What is the primary voltage compatibility issue with M48T58Y-70PC1?

A: The M48T58Y-70PC1 operates at 4.5V ~ 5.5V supply voltage, while the DS1501WN operates at 3V ~ 3.6V. Applications designed for 3V operation require circuit verification to confirm compatibility with the higher voltage specification of the M48T58Y-70PC1. Voltage level shifting or power supply modification may be necessary.

Q: Are both substitute parts ROHS3 compliant?

A: Yes. Both M48T35AV-10MH1F and M48T58Y-70PC1 are ROHS3 compliant, matching the DS1501WN's compliance status.

Q: What is the significance of the MSL rating difference?

A: The DS1501WN and M48T58Y-70PC1 have MSL rating 1 (Unlimited), allowing unlimited moisture exposure. The M48T35AV-10MH1F has MSL rating 3 (168 Hours), requiring controlled moisture exposure during storage and handling. Extended storage periods or high-humidity environments may require desiccant packaging and bake-out procedures before assembly.

Q: Which substitute part maintains the closest operating temperature range to the DS1501WN?

A: Neither substitute maintains the DS1501WN's extended operating temperature range of -40°C ~ 85°C. Both M48T35AV-10MH1F and M48T58Y-70PC1 operate within 0°C ~ 70°C. Applications requiring operation below 0°C or above 70°C cannot use these substitutes.

Q: What is the primary advantage of M48T35AV-10MH1F over M48T58Y-70PC1?

A: The M48T35AV-10MH1F provides lower timekeeping current consumption (2mA vs. 3mA) and operates within the DS1501WN's original 3V ~ 3.6V voltage range, eliminating voltage compatibility concerns. However, this advantage is offset by the requirement for Surface Mount implementation and stricter moisture sensitivity handling.

Q: Are the substitute parts available in the same packaging format as DS1501WN?

A: Only M48T58Y-70PC1 maintains the 28-DIP package format. M48T35AV-10MH1F uses 28-SOP package with SNAPHAT Sockets, requiring different PCB footprint and assembly approach.