DS1501W Equivalent & Substitute Parts

Part Overview

The DS1501W is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Analog Devices Inc./Maxim Integrated. This 28-DIP through-hole component provides 256 bytes of parallel interface memory with features including alarm capability, leap year compensation, non-volatile SRAM, square wave output, watchdog timer, and Y2K compliance. The DS1501W is classified as obsolete, making equivalent and substitute parts necessary for legacy system maintenance, repair, and redesign applications where continued component availability is required.

Substiute Parts

DS1501W

Analog Devices Inc./Maxim IntegratedIn Stock: 776DS1501W Datasheet

Current PartRFQ

DS1501W+

Analog Devices Inc./Maxim IntegratedIn Stock: 1172DS1501W+ Datasheet

DirectRFQ

BQ4802YPW

Texas InstrumentsIn Stock: 1928BQ4802YPW Datasheet

MFR RecommendedRFQ

DP8573AV/NOPB

Texas InstrumentsIn Stock: 4247DP8573AV/NOPB Datasheet

MFR RecommendedRFQ

M48T08-100PC1

STMicroelectronicsIn Stock: 1683M48T08-100PC1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DS1501W is determined by the following critical parameters:

Primary Substitution Criteria:

• Interface type: Parallel
• Time format capability: 24-hour format minimum
• Date format: YY-MM-DD-dd support
• Package compatibility: Through-hole or surface-mount variants acceptable based on application redesign tolerance
• Voltage supply range: Must support low-voltage operation (3V minimum for direct replacement)
• Features: Alarm and watchdog timer functionality
• Compliance: ROHS3 and REACH compliance maintained

Substitution Categories:

Category 1 - Direct Equivalent (Same Package, Same Manufacturer): DS1501W+ maintains identical electrical specifications, packaging (28-DIP), and feature set as the main part. This represents a direct pin-for-pin replacement with no design modification required.

Category 2 - Functional Equivalent (Different Package, Different Manufacturer): BQ4802YPW (Texas Instruments, 28-TSSOP surface-mount) and DP8573AV/NOPB (Texas Instruments, 28-LCC surface-mount) provide equivalent RTC functionality with parallel interface and required features. These require PCB redesign due to package change from through-hole to surface-mount.

Category 3 - Compatible Equivalent (Same Package, Different Manufacturer): M48T08-100PC1 (STMicroelectronics, 28-DIP through-hole) maintains the same package footprint as DS1501W, enabling direct board-level substitution without layout modification.

Parameter Comparison

Engineering Selection Recommendations

DS1501W+ (Direct Equivalent): Select this part for immediate replacement in existing designs. Maintains identical electrical specifications, packaging, and feature set. Product status is obsolete, matching the original part. Suitable for legacy system repairs and maintenance where no design modification is acceptable. ROHS3 and REACH compliance maintained.

M48T08-100PC1 (Through-Hole Compatible): Select this part for through-hole PCB designs requiring component substitution without layout redesign. Maintains 28-DIP package footprint compatible with DS1501W board positions. Product status is active, ensuring long-term availability. Operating temperature range matches original specification (0°C ~ 70°C). ROHS3 and REACH compliance maintained. Voltage supply range (4.75V ~ 5.5V) differs from original; verify power supply compatibility in target application.

BQ4802YPW (Surface-Mount Alternative): Select this part for applications permitting PCB redesign to surface-mount technology. Product status is active with superior long-term availability. Voltage supply range (4.5V ~ 5.5V) requires power supply modification from original 3V ~ 3.6V specification. Timekeeping current is lower (1.5mA typical) compared to original (4mA maximum). Requires PCB layout modification due to 28-TSSOP package. ROHS3 and REACH compliance maintained.

DP8573AV/NOPB (Extended Temperature Range): Select this part for applications requiring extended operating temperature range (-40°C ~ 85°C) beyond original specification (0°C ~ 70°C). Product status is active. Voltage supply range (4.5V ~ 5.5V) requires power supply modification. Timekeeping current is significantly lower (1µA @ 5V) enabling reduced power consumption. Requires PCB layout modification due to 28-LCC surface-mount package. MSL rating is 2A (4 weeks) versus original 1 (unlimited). ROHS3 and REACH compliance maintained.

Frequently Asked Questions (FAQ)

Q: Can DS1501W+ be used as a direct replacement for DS1501W? A: Yes. DS1501W+ is a direct equivalent with identical electrical specifications, 28-DIP package, and feature set. No design modification is required.

Q: What is the primary difference between DS1501W and M48T08-100PC1? A: Both use 28-DIP through-hole packaging and maintain compatible parallel interfaces. M48T08-100PC1 requires higher supply voltage (4.75V ~ 5.5V versus 3V ~ 3.6V). Verify power supply compatibility before substitution.

Q: Why do BQ4802YPW and DP8573AV/NOPB require higher supply voltages? A: These Texas Instruments parts are designed for standard 5V logic systems. DS1501W operates at lower voltage (3V ~ 3.6V). Applications using 5V power supplies can accommodate these substitutes; 3V systems require voltage regulation modification.

Q: Can surface-mount parts (BQ4802YPW, DP8573AV/NOPB) replace through-hole DS1501W without PCB modification? A: No. Surface-mount packages require PCB redesign. Through-hole boards cannot directly accommodate surface-mount components. PCB layout modification is mandatory.

Q: Which substitute part has the lowest timekeeping current consumption? A: DP8573AV/NOPB operates at 1µA @ 5V, significantly lower than DS1501W (4mA @ 3V ~ 3.6V). This part is suitable for battery-powered applications prioritizing low power consumption.

Q: Are all substitute parts ROHS3 compliant? A: Yes. DS1501W+, BQ4802YPW, DP8573AV/NOPB, and M48T08-100PC1 are all ROHS3 compliant and REACH unaffected.

Q: What is the MSL (Moisture Sensitivity Level) difference between parts? A: DS1501W, DS1501W+, BQ4802YPW, and M48T08-100PC1 have MSL 1 (unlimited shelf life). DP8573AV/NOPB has MSL 2A (4-week shelf life), requiring controlled storage conditions.

Q: Which substitute part maintains the same operating temperature range as DS1501W? A: DS1501W+, BQ4802YPW, and M48T08-100PC1 all operate within 0°C ~ 70°C. DP8573AV/NOPB extends to -40°C ~ 85°C.

Q: Can DS1501W be substituted in new designs? A: No. DS1501W is obsolete. New designs should use active-status alternatives: M48T08-100PC1 (through-hole), BQ4802YPW, or DP8573AV/NOPB (surface-mount).