DS17485SN-5+ Equivalent & Substitute Parts

Part Overview

The DS17485SN-5+ is a Real Time Clock (RTC) IC with Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This device provides 4KB of parallel interface memory with integrated timekeeping, alarm, and calendar features. The product is currently obsolete, making equivalent substitute parts necessary for ongoing system support, maintenance, and new design implementations where legacy compatibility or similar functionality is required.

Substiute Parts

DS17485SN-5+

Analog Devices Inc./Maxim IntegratedIn Stock: 955DS17485SN-5+ Datasheet

Current PartRFQ

BQ4802LYDWR

Texas InstrumentsIn Stock: 3828BQ4802LYDWR Datasheet

MFR RecommendedRFQ

M48T08Y-10MH1F

STMicroelectronicsIn Stock: 1165M48T08Y-10MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DS17485SN-5+ is determined by the following critical parameters:

• Interface Type: Parallel interface requirement
• Time/Date Format: HH:MM:SS (12/24 hr) and YY-MM-DD-dd format support
• Supply Voltage Compatibility: Operating voltage range and battery backup voltage
• Package Type: Surface mount SOIC/SOP variants
• Functional Features: Alarm, calendar, and timekeeping capabilities
• Compliance: RoHS3 compliance and MSL rating

The substitute parts identified (BQ4802LYDWR and M48T08Y-10MH1F) maintain parallel interface architecture and core RTC/Clock-Calendar functionality. However, each substitute presents distinct trade-offs in voltage specifications, package configuration, and feature sets that must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

BQ4802LYDWR (Texas Instruments)

This substitute is active and ROHS3 compliant with unlimited MSL rating. It maintains parallel interface and full 12/24-hour time format support. The primary consideration is voltage specification: the BQ4802LYDWR operates at 2.7V ~ 3.6V supply, which differs from the DS17485SN-5+ 4.5V ~ 5.5V range. This device is suitable for low-voltage applications and demonstrates lower timekeeping current consumption (1.5mA typical). Pin count increases from 24 to 28, requiring PCB layout modification.

M48T08Y-10MH1F (STMicroelectronics)

This substitute is active and ROHS3 compliant, maintaining the 4.5V ~ 5.5V supply voltage range and equivalent timekeeping current specification of the original part. Time format support is limited to 24-hour operation (no 12-hour mode). The package changes from 24-SOIC to 28-SOP with SNAPHAT Sockets, requiring PCB redesign. MSL rating is 3 (168 hours), indicating higher moisture sensitivity compared to the original part's unlimited rating.

Frequently Asked Questions (FAQ)

Q: Can BQ4802LYDWR directly replace DS17485SN-5+ without circuit modification?

A: No. The BQ4802LYDWR operates at 2.7V ~ 3.6V supply voltage, while the DS17485SN-5+ requires 4.5V ~ 5.5V. Direct substitution requires voltage regulation or system redesign. Additionally, pin count increases from 24 to 28, necessitating PCB layout changes.

Q: Is M48T08Y-10MH1F compatible with 12-hour time format applications?

A: No. The M48T08Y-10MH1F supports only 24-hour time format, whereas the DS17485SN-5+ supports both 12-hour and 24-hour formats. Applications requiring 12-hour operation cannot use this substitute without firmware modification.

Q: What are the package differences between these parts?

A: The DS17485SN-5+ uses 24-SOIC packaging. BQ4802LYDWR uses 28-SOIC (same body width of 0.295", 7.50mm but increased pin count). M48T08Y-10MH1F uses 28-SOP with SNAPHAT Sockets (wider body of 0.350", 8.89mm). All are surface mount, but PCB footprints differ significantly.

Q: Which substitute has the best environmental rating?

A: Both BQ4802LYDWR and DS17485SN-5+ have MSL rating of 1 (Unlimited). M48T08Y-10MH1F has MSL rating of 3 (168 hours), indicating greater moisture sensitivity and stricter handling requirements during assembly.

Q: Are all three parts RoHS3 compliant?

A: Yes. DS17485SN-5+, BQ4802LYDWR, and M48T08Y-10MH1F are all ROHS3 compliant.