SC189ASKTRT Equivalent & Substitute Parts

Part Overview

The SC189ASKTRT is a buck switching regulator IC manufactured by Semtech Corporation, designed for positive fixed 1V output applications with 1.5A output current capability. This device operates across a 2.9V to 5.5V input voltage range and features a 2.5MHz switching frequency with integrated synchronous rectification in a compact SC-74A (SOT-753) surface mount package.

The SC189ASKTRT carries a "Not For New Designs" product status, indicating that Semtech has discontinued active development and support for this component. This status necessitates identification of functionally equivalent alternatives for new circuit designs and ongoing production requirements where component availability or long-term support is a consideration.

Substiute Parts

SC189ASKTRT

Semtech CorporationIn Stock: 4403SC189ASKTRT Datasheet

Current PartRFQ

RT8010-10GQW

Richtek USA Inc.In Stock: 937RT8010-10GQW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SC189ASKTRT is determined by strict alignment of core electrical and mechanical parameters. The following criteria establish functional equivalence:

Primary Substitution Criteria:

• Function: Step-Down (Buck) topology
• Output Configuration: Positive fixed output
• Output Voltage: 1V fixed
• Input Voltage Range: Minimum 2.9V to 5.5V maximum (substitute must support this range or broader)
• Output Current: Minimum 1A (substitute rated for 1A or higher)
• Synchronous Rectifier: Integrated
• Mounting Type: Surface Mount
• RoHS3 Compliance: Required

Secondary Considerations:

• Switching Frequency: 1.5MHz to 2.5MHz range acceptable
• Operating Temperature: -40°C minimum to 85°C or higher maximum
• Package compatibility: Different packages acceptable if electrical specifications align

Parameter Comparison

Engineering Selection Recommendations

The RT8010-10GQW from Richtek USA Inc. qualifies as a functional substitute for the SC189ASKTRT based on alignment of core electrical specifications and compliance certifications.

Suitability Assessment:

The RT8010-10GQW maintains electrical equivalence in topology, output voltage, input voltage range, and synchronous rectification architecture. Both devices are ROHS3 compliant and operate across the required -40°C to 85°C temperature range, with the substitute supporting the full lower temperature specification.

Design Constraints:

Applications requiring output currents exceeding 1A must retain the SC189ASKTRT or identify alternative parts rated for 1.5A or higher. The RT8010-10GQW is suitable only for designs with maximum output current requirements of 1A.

Applications requiring junction temperatures above 85°C must retain the SC189ASKTRT or identify alternatives with higher temperature ratings.

The RT8010-10GQW uses a 6-WDFN package versus the SC-74A (SOT-753) package of the original part. PCB layout redesign is required to accommodate the different footprint, pinout, and thermal characteristics of the 6-WDFN Exposed Pad package.

Product Status Advantage:

The RT8010-10GQW carries an "Active" product status, indicating ongoing manufacturer support, continued availability, and potential for design improvements or derivative variants. This status provides long-term supply chain stability compared to the "Not For New Designs" status of the SC189ASKTRT.

Frequently Asked Questions (FAQ)

Q: Can the RT8010-10GQW directly replace the SC189ASKTRT without PCB modifications?

A: No. The RT8010-10GQW uses a 6-WDFN Exposed Pad package while the SC189ASKTRT uses SC-74A (SOT-753). Different footprints, pinouts, and thermal pad configurations require PCB layout redesign. Pin-to-pin compatibility does not exist between these packages.

Q: What is the maximum output current for the RT8010-10GQW?

A: The RT8010-10GQW is rated for 1A maximum output current. Applications requiring 1.5A output current cannot use this substitute and must identify alternative parts with higher current ratings.

Q: Are both parts RoHS3 compliant?

A: Yes. Both the SC189ASKTRT and RT8010-10GQW are ROHS3 compliant and REACH unaffected, meeting environmental and regulatory requirements for industrial and commercial applications.

Q: What is the temperature operating range difference?

A: The SC189ASKTRT operates to 125°C junction temperature, while the RT8010-10GQW operates to 85°C ambient temperature. For applications requiring operation above 85°C ambient, the SC189ASKTRT or higher-temperature-rated alternatives must be used.

Q: Why is the SC189ASKTRT marked "Not For New Designs"?

A: This status indicates Semtech has discontinued active development and support for this component. New circuit designs should use actively supported alternatives such as the RT8010-10GQW to ensure long-term availability, technical support, and potential design improvements.

Q: Are the switching frequencies compatible?

A: The SC189ASKTRT operates at 2.5MHz while the RT8010-10GQW operates at 1.5MHz. Both frequencies fall within acceptable ranges for buck regulator applications. The lower switching frequency of the RT8010-10GQW may result in larger output filter components but does not affect functional compatibility for fixed 1V output applications.

Q: What certifications apply to both parts?

A: Both parts are ROHS3 compliant, REACH unaffected, and classified under ECCN EAR99 with HTSUS code 8542.39.0001. Both meet the same regulatory and trade classification requirements.