DS1511W Equivalent & Substitute Parts

Part Overview

The DS1511W is a Real Time Clock (RTC) IC with Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This 28-DIP through-hole device provides 256 bytes of parallel interface memory with integrated timekeeping, alarm, leap year compensation, non-volatile SRAM, square wave output, watchdog timer, and Y2K compliance. The DS1511W is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing system support.

Substiute Parts

DS1511W

Analog Devices Inc./Maxim IntegratedIn Stock: 1278DS1511W Datasheet

Current PartRFQ

DS1511W+

Analog Devices Inc./Maxim IntegratedIn Stock: 2155DS1511W+ Datasheet

DirectRFQ

BQ4802LYDW

Texas InstrumentsIn Stock: 1993BQ4802LYDW Datasheet

MFR RecommendedRFQ

BQ4802LYPW

Texas InstrumentsIn Stock: 9564BQ4802LYPW Datasheet

MFR RecommendedRFQ

M48T12-150PC1

STMicroelectronicsIn Stock: 2537M48T12-150PC1 Datasheet

MFR RecommendedRFQ

M48T35-70PC1

STMicroelectronicsIn Stock: 7799M48T35-70PC1 Datasheet

MFR RecommendedRFQ

M48T35Y-70MH1F

STMicroelectronicsIn Stock: 1491M48T35Y-70MH1F Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the DS1511W is determined by the following critical parameters:

• Interface Type: Parallel interface requirement
• Time Format: 24-hour HH:MM:SS format support
• Date Format: YY-MM-DD-dd format support
• Operating Temperature Range: 0°C ~ 70°C
• Core Features: Alarm, Leap Year, Watchdog Timer functionality
• Mounting Compatibility: Through-hole or surface-mount alternatives with equivalent pinout functionality

Substitute parts are grouped into two categories:

Category 1 - Direct Pin-Compatible Replacement (Same Package)

• DS1511W+ (Analog Devices Inc./Maxim Integrated): Identical 28-DIP package, active product status, RoHS3 compliant

Category 2 - Functional Equivalents (Different Package/Voltage)

• BQ4802LYDW (Texas Instruments): 28-SOIC surface-mount package, 2.7V ~ 3.6V supply, 12/24-hour format
• BQ4802LYPW (Texas Instruments): 28-TSSOP surface-mount package, 2.7V ~ 3.6V supply, 12/24-hour format
• M48T12-150PC1 (STMicroelectronics): 24-DIP through-hole package, 4.5V ~ 5.5V supply, 24-hour format
• M48T35-70PC1 (STMicroelectronics): 28-DIP through-hole package, 4.75V ~ 5.5V supply, 24-hour format
• M48T35Y-70MH1F (STMicroelectronics): 28-SOP surface-mount package, 4.5V ~ 5.5V supply, 24-hour format

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Recommended for Existing Designs)

DS1511W+ is the primary substitute for the DS1511W. Both devices share identical electrical specifications, 28-DIP package configuration, and functional feature set. DS1511W+ is currently in active production status with RoHS3 compliance, addressing the obsolescence of the original DS1511W while maintaining full pin and functional compatibility.

For New Designs with Supply Voltage Flexibility

Texas Instruments BQ4802LYDW and BQ4802LYPW offer active product status and lower timekeeping current consumption (1.5mA typical versus 4mA maximum). These devices support 12/24-hour time format and operate across 2.7V ~ 3.6V supply range. BQ4802LYDW uses 28-SOIC surface-mount packaging; BQ4802LYPW uses 28-TSSOP surface-mount packaging. Both require PCB redesign for surface-mount implementation.

For Through-Hole Designs with 5V Supply Systems

STMicroelectronics M48T35-70PC1 maintains through-hole 28-DIP packaging with 4.75V ~ 5.5V supply operation and reduced timekeeping current (2mA). This device is suitable for legacy 5V system architectures. M48T12-150PC1 provides 24-DIP through-hole packaging for systems with reduced pin count requirements and 4.5V ~ 5.5V supply operation.

For Surface-Mount Designs with 5V Supply Systems

STMicroelectronics M48T35Y-70MH1F provides 28-SOP surface-mount packaging with 4.5V ~ 5.5V supply operation. This device is suitable for compact surface-mount implementations in 5V system environments.

All substitute parts maintain parallel interface architecture, support 24-hour time format with YY-MM-DD-dd date format, and operate across the 0°C ~ 70°C temperature range. All active substitutes carry RoHS3 compliance and REACH unaffected status.

Frequently Asked Questions (FAQ)

Q: Can DS1511W+ be used as a direct replacement for DS1511W?

A: Yes. DS1511W+ is pin-compatible and functionally equivalent to DS1511W. Both use 28-DIP through-hole packaging, identical supply voltage ranges (3V ~ 3.6V), and support the same time/date formats, features, and operating temperature range. DS1511W+ is currently in active production with RoHS3 compliance.

Q: What are the key differences between the Analog Devices and Texas Instruments substitutes?

A: Analog Devices DS1511W+ maintains the original 3V ~ 3.6V supply voltage and 4mA timekeeping current. Texas Instruments BQ4802 series devices operate at 2.7V ~ 3.6V with lower timekeeping current (1.5mA typical) and support both 12/24-hour time formats. BQ4802LYDW uses 28-SOIC packaging; BQ4802LYPW uses 28-TSSOP packaging. Both require surface-mount PCB implementation.

Q: Can I use STMicroelectronics M48T35 series devices in a 3V system?

A: No. STMicroelectronics M48T35 series devices require 4.75V ~ 5.5V supply voltage and are not compatible with 3V systems. These devices are suitable only for 5V system architectures.

Q: What is the difference between M48T35-70PC1 and M48T35Y-70MH1F?

A: M48T35-70PC1 uses 28-DIP through-hole packaging suitable for through-hole PCB assembly. M48T35Y-70MH1F uses 28-SOP surface-mount packaging with SNAPHAT sockets for surface-mount PCB assembly. Both operate at 4.75V ~ 5.5V supply voltage with 2mA timekeeping current and support identical time/date formats.

Q: Are all substitute parts RoHS compliant?

A: DS1511W is RoHS non-compliant. All active substitute parts (DS1511W+, BQ4802LYDW, BQ4802LYPW, M48T12-150PC1, M48T35-70PC1, M48T35Y-70MH1F) are RoHS3 compliant.

Q: Which substitute should I select for a new design?

A: For 3V systems with through-hole requirements, use DS1511W+. For 3V systems with surface-mount requirements and lower power consumption, use BQ4802LYDW (28-SOIC) or BQ4802LYPW (28-TSSOP). For 5V systems with through-hole requirements, use M48T35-70PC1. For 5V systems with surface-mount requirements, use M48T35Y-70MH1F.

Q: Do all substitute parts support the same parallel interface?

A: Yes. All substitute parts maintain parallel interface architecture compatible with the DS1511W. Pin configuration differences exist between through-hole and surface-mount packages; refer to individual device datasheets for pinout details.