DS1558W Equivalent & Substitute Parts

Part Overview

The DS1558W is a Real Time Clock (RTC) IC with integrated clock/calendar functionality in a 48-LQFP surface mount package, manufactured by Analog Devices Inc./Maxim Integrated. This device provides parallel interface timekeeping with alarm, leap year compensation, watchdog timer, and Y2K features. The DS1558W is classified as obsolete, making identification of compatible substitute parts essential for ongoing system support and new design implementations.

Substiute Parts

DS1558W

Analog Devices Inc./Maxim IntegratedIn Stock: 29056DS1558W Datasheet

Current PartRFQ

DS1558W+

Analog Devices Inc./Maxim IntegratedIn Stock: 1367DS1558W+ Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DS1558W is determined by strict equivalence across the following critical parameters:

• Package / Case: 48-LQFP (7x7) form factor
• Interface Type: Parallel interface architecture
• Voltage Supply Range: 2.97V ~ 3.63V nominal operation
• Battery Supply Range: 2.5V ~ 3.7V backup operation
• Timekeeping Current: 2mA @ 3.3V maximum
• Operating Temperature Range: -40°C ~ 85°C
• Time and Date Format: HH:MM:SS (24 hr) and YY-MM-DD-dd
• Core Features: Alarm, Leap Year, Watchdog Timer, Y2K support

The DS1558W+ meets all electrical and mechanical substitution criteria, maintaining identical functional specifications while offering improved product status and compliance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The DS1558W+ is the direct substitute for the DS1558W based on identical electrical and mechanical specifications. Selection of the DS1558W+ is supported by the following factors:

• Active product status ensures ongoing manufacturer support and availability
• ROHS3 compliance meets current environmental and regulatory requirements
• Moisture Sensitivity Level 1 (Unlimited) provides superior handling and storage characteristics compared to MSL 3 (168 Hours)
• Identical functional parameters guarantee drop-in compatibility in existing circuit designs
• Same 48-LQFP package and parallel interface eliminate redesign requirements

Frequently Asked Questions (FAQ)

Q: Can DS1558W+ be used as a direct replacement for DS1558W in existing designs?

A: Yes. The DS1558W+ maintains identical electrical specifications, package form factor, and functional features. No circuit modifications are required for substitution.

Q: What is the significance of the product status difference between DS1558W and DS1558W+?

A: The DS1558W is classified as obsolete, indicating discontinued manufacturing and limited future availability. The DS1558W+ is active, ensuring continued supply and manufacturer support.

Q: How do the RoHS compliance ratings differ between these parts?

A: The DS1558W is RoHS non-compliant, while the DS1558W+ is ROHS3 compliant. This distinction is relevant for applications subject to environmental regulations and procurement policies requiring RoHS compliance.

Q: What does Moisture Sensitivity Level (MSL) indicate for these components?

A: MSL defines the maximum time a component can be exposed to moisture before soldering. DS1558W has MSL 3 (168 hours maximum), while DS1558W+ has MSL 1 (unlimited). The DS1558W+ offers superior moisture tolerance and reduced handling constraints.

Q: Are the 48-LQFP packages identical between DS1558W and DS1558W+?

A: Yes. Both parts use the same 48-LQFP (7x7) surface mount package with identical pin configuration and mechanical dimensions.

Q: What interface type do these RTC devices use?

A: Both the DS1558W and DS1558W+ use a parallel interface for communication with host systems.