NR885K Equivalent & Substitute Parts

Part Overview

The NR885K is a buck switching regulator IC manufactured by Sanken Electric USA Inc., designed for positive adjustable output applications with 3A output current capability. This component operates as a step-down converter with adjustable output voltage ranging from 0.8V to 14V and input voltage range of 4.5V to 18V. The device features a synchronous rectifier and is housed in an 8-SOIC package with exposed pad for enhanced thermal performance.

The NR885K is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain reliability, and support ongoing production requirements for applications utilizing this regulator topology.

Substiute Parts

NR885K

Sanken Electric USA Inc.In Stock: 3864NR885K Datasheet

Current PartRFQ

RT7263AZSP

Richtek USA Inc.In Stock: 3634RT7263AZSP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the NR885K is determined by the following critical parameters:

• Topology & Function: Buck (step-down) converter with positive adjustable output
• Output Current Rating: 3A minimum
• Input Voltage Range: Minimum 4.5V, maximum at least 18V
• Output Voltage Range: Adjustable from minimum 0.8V or lower to maximum 14V or higher
• Number of Outputs: Single output configuration
• Synchronous Rectifier: Required for efficiency equivalence
• Package Compatibility: 8-SOIC with exposed pad, surface mount
• Operating Temperature Range: -40°C to 85°C minimum
• Regulatory Compliance: RoHS compliance required

The RT7263AZSP meets these substitution criteria across all critical electrical and mechanical parameters while maintaining functional equivalence for buck regulator applications.

Parameter Comparison

Engineering Selection Recommendations

The RT7263AZSP qualifies as a functional equivalent for the obsolete NR885K based on the following engineering criteria:

Electrical Equivalence: Both devices operate as adjustable buck regulators with identical 3A output current, matching input minimum of 4.5V, and equivalent minimum output voltage of 0.8V/0.808V. The RT7263AZSP provides extended maximum input voltage (21V vs. 18V) and maximum output voltage (15V vs. 14V), offering broader application flexibility without compromising compatibility with NR885K-based designs.

Thermal & Operating Conditions: Identical operating temperature range (-40°C to 85°C) ensures equivalent thermal performance characteristics across the specified industrial temperature spectrum.

Regulatory Compliance: Both devices maintain RoHS compliance. The RT7263AZSP carries ROHS3 certification, representing current regulatory alignment. The NR885K's RoHS Compliant status and the RT7263AZSP's ROHS3 Compliant status both satisfy modern environmental and hazardous substance restrictions.

Product Status: The RT7263AZSP is classified as Active, ensuring ongoing availability, manufacturing support, and supply chain continuity compared to the NR885K's Obsolete status.

Package Considerations: Both devices utilize 8-SOIC packages with exposed pads. The RT7263AZSP package width is 3.90mm compared to the NR885K's 4.40mm. This dimensional difference is within standard PCB layout tolerance for 8-SOIC footprints and does not preclude direct substitution on existing designs with standard 8-SOIC land patterns.

Frequently Asked Questions (FAQ)

Q: Can the RT7263AZSP directly replace the NR885K without PCB modifications?

A: The RT7263AZSP is electrically and functionally equivalent to the NR885K. Both devices use 8-SOIC packages with exposed pads and identical pin configurations for buck regulator operation. Standard 8-SOIC footprints accommodate both package width variants (3.90mm and 4.40mm). Direct substitution is possible without PCB redesign for applications within the specified electrical parameters.

Q: What is the significance of the higher switching frequency in the RT7263AZSP (500kHz vs. 350kHz)?

A: The RT7263AZSP operates at 500kHz compared to the NR885K's 350kHz. Higher switching frequency typically enables smaller external component values (inductors and capacitors) for equivalent filtering performance. This may reduce board space requirements and component costs. The higher frequency does not compromise compatibility; it represents an engineering improvement in the substitute device.

Q: Are there any compliance or certification differences between these devices?

A: Both devices are RoHS compliant. The NR885K carries RoHS Compliant certification, while the RT7263AZSP carries ROHS3 Compliant certification. ROHS3 represents the current regulatory standard. Both certifications satisfy modern environmental and hazardous substance restrictions. The RT7263AZSP's ROHS3 status provides alignment with current regulatory requirements.

Q: How do the input and output voltage ranges compare?

A: The RT7263AZSP provides extended voltage ranges: maximum input voltage of 21V (vs. 18V) and maximum output voltage of 15V (vs. 14V). Minimum voltages are identical (4.5V input, 0.8V output). The extended ranges in the substitute device do not affect compatibility with NR885K designs; they provide additional design flexibility for applications requiring higher voltage operation.

Q: What is the moisture sensitivity level difference, and does it affect handling?

A: The NR885K has MSL 1 (Unlimited), while the RT7263AZSP has MSL 3 (168 Hours). MSL 3 requires storage in controlled humidity conditions and has a 168-hour floor life after moisture exposure. This represents a more stringent handling requirement for the substitute device. Proper moisture control during storage and assembly is necessary to maintain device reliability.

Q: Is the RT7263AZSP suitable for all applications currently using the NR885K?

A: The RT7263AZSP is suitable for applications within the specified electrical parameters of both devices. The overlapping voltage ranges (4.5V to 18V input, 0.8V to 14V output) and identical 3A output current ensure functional compatibility. Applications requiring input voltages above 18V or output voltages above 14V can leverage the RT7263AZSP's extended ranges. Verify specific application requirements against the datasheet specifications of both devices.