AOZ1242DI Equivalent & Substitute Parts

Part Overview

The AOZ1242DI is a buck switching regulator IC from Alpha & Omega Semiconductor Inc., designed for positive adjustable step-down voltage regulation with 3A output current capability. This device operates across a 4.5V to 32V input range and delivers adjustable output voltage from 0.8V to 32V. The part is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity.

Substiute Parts

AOZ1242DI

Alpha & Omega Semiconductor Inc.In Stock: 1253AOZ1242DI Datasheet

Current PartRFQ

L7981TR

STMicroelectronicsIn Stock: 1725L7981TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AOZ1242DI is determined by the following critical electrical and mechanical parameters:

• Output Current Rating: 3A minimum required
• Input Voltage Range: Minimum 4.5V, maximum coverage of 32V or higher
• Output Voltage Adjustability: Adjustable topology with minimum output voltage at or below 0.8V
• Topology: Buck (step-down) switching regulator
• Package Compatibility: Surface mount, 8-pin DFN or equivalent footprint
• Regulatory Compliance: ROHS3 compliance and EAR99 classification

The L7981TR from STMicroelectronics meets these substitution criteria as an active product with equivalent electrical performance across the specified parameter ranges.

Parameter Comparison

Engineering Selection Recommendations

The L7981TR qualifies as a functional substitute for the obsolete AOZ1242DI based on matching core electrical specifications: identical 3A output current, 4.5V minimum input voltage, adjustable positive output topology, and single-output configuration. Both devices maintain ROHS3 compliance and EAR99 classification.

Key considerations for selection:

• Product Status: L7981TR is an active product with ongoing manufacturer support, whereas AOZ1242DI is obsolete. This favors L7981TR for new designs and long-term production.
• Input Voltage Maximum: AOZ1242DI supports 32V maximum input; L7981TR is rated to 28V. Applications requiring input voltages above 28V cannot use L7981TR as a direct substitute.
• Output Voltage Range: L7981TR minimum output voltage is 0.6V compared to AOZ1242DI at 0.8V, providing greater flexibility for lower voltage applications.
• Package Footprint: AOZ1242DI uses 8-WDFN (5x4mm) while L7981TR uses 8-VFDFN (3x3mm). PCB layout modifications are required for physical substitution.
• Operating Temperature: L7981TR junction temperature rating of 150°C exceeds AOZ1242DI ambient rating of 85°C, offering improved thermal performance.

Frequently Asked Questions (FAQ)

Q: Can L7981TR directly replace AOZ1242DI on existing PCBs?

A: No. While electrically compatible for most applications, the package footprints differ: AOZ1242DI is 8-WDFN (5x4mm) and L7981TR is 8-VFDFN (3x3mm). PCB redesign is required for physical substitution.

Q: What is the maximum input voltage for L7981TR?

A: L7981TR is rated for 4.5V to 28V input. Applications requiring 28V to 32V input operation cannot use L7981TR as a substitute for AOZ1242DI.

Q: Are both devices RoHS compliant?

A: Yes. Both AOZ1242DI and L7981TR are ROHS3 compliant and carry EAR99 classification.

Q: Why is AOZ1242DI listed as obsolete?

A: Product status reflects manufacturer discontinuation. L7981TR is an active product with current manufacturing and technical support availability.

Q: What is the switching frequency difference between these devices?

A: AOZ1242DI operates at a fixed 370kHz switching frequency. L7981TR operates across a 250kHz to 1MHz range, which encompasses the AOZ1242DI frequency and provides design flexibility.

Q: Can L7981TR achieve lower output voltages than AOZ1242DI?

A: Yes. L7981TR minimum adjustable output voltage is 0.6V compared to AOZ1242DI at 0.8V, enabling designs requiring lower regulated voltages.