SC189LSKTRT Equivalent & Substitute Parts

Part Overview

The SC189LSKTRT is a buck switching regulator IC manufactured by Semtech Corporation, designed for positive fixed 1.8V output applications with 1.5A output current capability. The device is packaged in SC-74A (SOT-753) surface mount configuration and operates across an input voltage range of 2.9V to 5.5V with a switching frequency of 2.5MHz. This part carries a "Not For New Designs" status, making identification of active equivalent alternatives essential for ongoing production and new design initiatives.

Substiute Parts

SC189LSKTRT

Semtech CorporationIn Stock: 4892SC189LSKTRT Datasheet

Current PartRFQ

RT8010-18GQW

Richtek USA Inc.In Stock: 5585RT8010-18GQW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SC189LSKTRT is determined by the following critical parameters:

• Output voltage specification (1.8V fixed)
• Buck topology with positive output configuration
• Single output configuration
• Input voltage compatibility (minimum 2.9V, maximum 5.5V)
• Output current capability (minimum 1.5A required)
• Surface mount technology
• Synchronous rectifier implementation
• RoHS compliance status

The RT8010-18GQW qualifies as a functional equivalent based on matching output voltage, topology, output configuration, and synchronous rectifier implementation. Differences in output current rating, switching frequency, operating temperature range, and package form factor must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The RT8010-18GQW represents an active alternative to the SC189LSKTRT for applications requiring 1.8V fixed output buck regulation. Key considerations for selection include:

Output current capacity: The RT8010-18GQW provides 1A maximum output current compared to the SC189LSKTRT's 1.5A rating. Applications requiring sustained output currents above 1A must verify that the RT8010-18GQW meets load requirements.

Operating temperature range: The SC189LSKTRT operates to 125°C junction temperature, while the RT8010-18GQW operates to 85°C ambient temperature. Thermal environment assessment is necessary for high-temperature applications.

Package transition: The SC189LSKTRT uses SOT-23-5 packaging while the RT8010-18GQW uses 6-WDFN with exposed pad. PCB layout modifications are required for package conversion.

Input voltage floor: The RT8010-18GQW accepts input voltages as low as 2.5V, providing broader input range compatibility compared to the SC189LSKTRT's 2.9V minimum.

Switching frequency: The RT8010-18GQW operates at 1.5MHz versus the SC189LSKTRT's 2.5MHz. Lower switching frequency may affect output ripple characteristics and component selection for filtering networks.

Product status: The RT8010-18GQW carries Active status, ensuring continued availability and support for new designs, whereas the SC189LSKTRT is designated Not For New Designs.

Frequently Asked Questions (FAQ)

Q: Can the RT8010-18GQW directly replace the SC189LSKTRT without PCB modifications?

A: No. The RT8010-18GQW uses 6-WDFN packaging while the SC189LSKTRT uses SOT-23-5 packaging. Different pinout configurations and footprints require PCB layout redesign. Pin-to-pin compatibility does not exist between these packages.

Q: What is the impact of the 0.5A output current difference between these parts?

A: The RT8010-18GQW's 1A maximum output current is 0.5A lower than the SC189LSKTRT's 1.5A rating. Applications with load currents between 1A and 1.5A cannot use the RT8010-18GQW. Load current analysis is mandatory before substitution.

Q: How does the switching frequency difference affect circuit design?

A: The RT8010-18GQW operates at 1.5MHz compared to the SC189LSKTRT's 2.5MHz. Lower switching frequency typically results in larger output filter components and potentially higher output voltage ripple. Input and output filter designs must be recalculated for the lower frequency.

Q: Are there compliance differences between these parts?

A: Both parts are RoHS compliant. The SC189LSKTRT is RoHS Compliant while the RT8010-18GQW is ROHS3 Compliant. Both meet environmental compliance requirements for their respective manufacturing periods.

Q: What is the significance of the input voltage range difference?

A: The RT8010-18GQW accepts input voltages starting at 2.5V, while the SC189LSKTRT requires minimum 2.5V input. The RT8010-18GQW provides 0.4V lower minimum input threshold, enabling operation in lower voltage supply scenarios.

Q: Does the operating temperature range difference affect reliability?

A: The SC189LSKTRT operates to 125°C junction temperature while the RT8010-18GQW operates to 85°C ambient temperature. Applications in high-temperature environments may exceed the RT8010-18GQW's thermal limits. Thermal analysis of the specific application environment is required.

Q: Are both parts suitable for new design implementations?

A: The SC189LSKTRT carries "Not For New Designs" status, indicating Semtech has discontinued active support for new applications. The RT8010-18GQW carries Active status, making it the appropriate choice for new design initiatives requiring 1.8V buck regulation.