MP9115DQT-LF-Z Equivalent & Substitute Parts

Part Overview

The MP9115DQT-LF-Z is a buck switching regulator IC manufactured by Monolithic Power Systems Inc., designed for positive adjustable output applications. This device delivers 2.5A output current with an adjustable output voltage range from 0.8V to 6V, operating from a 2.7V to 6V input supply. The component is classified as Not For New Designs, indicating it has been superseded in the manufacturer's product roadmap. Finding equivalent or substitute parts is necessary for ongoing production support, legacy system maintenance, and design flexibility when the primary part becomes unavailable.

Substiute Parts

MP9115DQT-LF-Z

Monolithic Power Systems Inc.In Stock: 67231MP9115DQT-LF-Z Datasheet

Current PartRFQ

RT8068AZQW

Richtek USA Inc.In Stock: 35233RT8068AZQW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MP9115DQT-LF-Z is determined by the following critical parameters:

• Package Compatibility: Both main and substitute parts must use the 10-WFDFN Exposed Pad package to ensure PCB layout and thermal management compatibility.
• Topology & Function: Buck switching regulator topology with positive adjustable output configuration.
• Output Voltage Range: Substitute must support the required output voltage window. The MP9115DQT-LF-Z requires 0.8V minimum output; substitutes with lower minimum output voltage (0.6V) are acceptable as they provide extended range capability.
• Output Current: Substitute must meet or exceed the 2.5A output current requirement.
• Input Voltage Range: Substitute input range must encompass or overlap the 2.7V to 6V specification.
• Synchronous Rectification: Both parts include synchronous rectifier functionality for efficiency.
• Regulatory Compliance: RoHS3 compliance is mandatory; REACH unaffected status is required.

The RT8068AZQW qualifies as a substitute based on these criteria.

Parameter Comparison

Engineering Selection Recommendations

The RT8068AZQW is qualified as a substitute for the MP9115DQT-LF-Z based on the following engineering criteria:

Product Status Advantage: The RT8068AZQW carries Active product status, whereas the MP9115DQT-LF-Z is marked Not For New Designs. This makes the RT8068AZQW the preferred choice for long-term availability and supply chain stability.

Regulatory Compliance: Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying environmental and regulatory requirements.

Performance Characteristics: The RT8068AZQW exceeds the output current specification (3A versus 2.5A), providing design margin. The output voltage range differs slightly: the RT8068AZQW minimum is 0.6V (lower than the 0.8V minimum of the MP9115DQT-LF-Z), and the maximum is 5.5V (lower than the 6V maximum). For applications requiring output voltages above 5.5V or below 0.6V, the MP9115DQT-LF-Z remains the only option.

Package Compatibility: Both devices use the 10-WFDFN Exposed Pad package, ensuring direct PCB layout compatibility.

Thermal Considerations: The RT8068AZQW operates to 105°C junction temperature, compared to 85°C ambient for the MP9115DQT-LF-Z. The RT8068AZQW carries MSL-3 rating versus MSL-1 for the MP9115DQT-LF-Z, requiring stricter moisture control during storage and handling.

Frequently Asked Questions (FAQ)

Q: Can the RT8068AZQW directly replace the MP9115DQT-LF-Z without PCB modifications?

A: Yes, both parts use the 10-WFDFN Exposed Pad package with identical pinout compatibility. No PCB layout changes are required for package substitution.

Q: What is the key difference in output voltage capability between these parts?

A: The MP9115DQT-LF-Z supports output voltages from 0.8V to 6V, while the RT8068AZQW supports 0.6V to 5.5V. If your application requires output voltages above 5.5V, the MP9115DQT-LF-Z is required. For applications within the 0.8V to 5.5V range, both parts are compatible.

Q: Why is the RT8068AZQW preferred despite being from a different manufacturer?

A: The RT8068AZQW holds Active product status, ensuring ongoing manufacturing support and long-term availability. The MP9115DQT-LF-Z is marked Not For New Designs, indicating it will eventually be discontinued. For new production runs or long-term supply chain planning, the RT8068AZQW is the recommended choice.

Q: Does the switching frequency difference affect circuit design?

A: The MP9115DQT-LF-Z operates at 1.2MHz while the RT8068AZQW operates at 1MHz. This 200kHz difference may require recalculation of output filter component values (inductor and capacitor) to maintain the same ripple voltage and current characteristics. Verify filter design parameters for your specific application.

Q: What are the moisture sensitivity implications?

A: The MP9115DQT-LF-Z carries MSL-1 (Unlimited shelf life), while the RT8068AZQW carries MSL-3 (168-hour floor life after moisture exposure). The RT8068AZQW requires more stringent moisture control during storage, handling, and assembly. Ensure proper baking procedures are followed if the part has exceeded its floor life.

Q: Are there any temperature range limitations I should consider?

A: The MP9115DQT-LF-Z operates from -40°C to 85°C ambient temperature, while the RT8068AZQW operates from -10°C to 105°C junction temperature. If your application requires operation below -10°C, the MP9115DQT-LF-Z is required. For standard industrial and commercial temperature ranges, both parts are suitable.

Q: Can I use the RT8068AZQW's higher current rating (3A vs 2.5A) to improve thermal performance?

A: The higher current rating provides design margin and may reduce thermal stress under full-load conditions. However, actual thermal performance depends on PCB layout, copper area, thermal vias, and external heat dissipation. Verify thermal performance through simulation or testing for your specific application.