L4938ED Linear Voltage Regulator IC Equivalent & Substitute Parts

Part Overview

The L4938ED is a linear voltage regulator IC manufactured by STMicroelectronics, classified as a Power Management (PMIC) component. This device functions as a positive adjustable (fixed) output regulator with dual output capability, delivering 100mA and 400mA outputs respectively. The L4938ED is currently listed as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. The availability of substitute parts ensures design continuity and supply chain reliability for applications requiring this specific regulator topology and electrical performance.

Substiute Parts

L4938ED

STMicroelectronicsIn Stock: 7489L4938ED Datasheet

Current PartRFQ

L4938EDTR-E

STMicroelectronicsIn Stock: 1170L4938EDTR-E Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the L4938ED is determined by strict equivalence across all critical electrical and mechanical parameters. The substitute part must maintain identical specifications in the following categories:

Electrical Parameters:

• Output configuration (positive)
• Output type (adjustable/fixed)
• Number of regulators (dual output)
• Input voltage maximum (28V)
• Output voltage range (4.9V to 5.1V)
• Dropout voltage specifications (0.4V @ 100mA, 0.6V @ 400mA)
• Output current ratings (100mA, 400mA)
• Control features (Enable, Reset)
• Protection features (Over Temperature)
• Operating temperature range (-40°C ~ 150°C)

Mechanical Parameters:

• Mounting type (Surface Mount)
• Package type (20-SOIC, 0.295", 7.50mm Width)

Compliance Parameters:

• RoHS3 compliance
• REACH unaffected status
• Moisture sensitivity level (MSL 3)

The L4938EDTR-E meets all substitution criteria as a direct equivalent part, with the primary distinction being active product status versus the obsolete status of the L4938ED.

Parameter Comparison

Engineering Selection Recommendations

The L4938EDTR-E is a direct functional equivalent to the L4938ED with complete electrical and mechanical parameter alignment. The primary distinction is product lifecycle status: the L4938ED is obsolete while the L4938EDTR-E maintains active status with STMicroelectronics.

For new designs and production applications, the L4938EDTR-E is the appropriate selection. Both parts maintain identical RoHS3 compliance and REACH unaffected status, ensuring regulatory alignment across applications. The MSL 3 rating (168 Hours) applies uniformly to both parts, requiring equivalent moisture control during storage and handling.

The identical 20-SOIC package footprint (0.295", 7.50mm Width) ensures direct PCB layout compatibility without design modification. Pin configuration and electrical interface characteristics remain unchanged between the two parts.

Frequently Asked Questions (FAQ)

Q: Can the L4938EDTR-E be used as a direct replacement for the L4938ED in existing designs?

A: Yes. The L4938EDTR-E is electrically and mechanically identical to the L4938ED across all specified parameters. The parts share identical package geometry, pin configuration, voltage specifications, current ratings, and control features. Direct substitution is supported without circuit modification.

Q: What is the primary reason for substituting the L4938ED?

A: The L4938ED is classified as obsolete. The L4938EDTR-E maintains active product status with STMicroelectronics, ensuring ongoing availability and supply chain continuity for new production and design implementations.

Q: Are there any compliance differences between the L4938ED and L4938EDTR-E?

A: No. Both parts maintain identical RoHS3 compliance, REACH unaffected status, and MSL 3 moisture sensitivity rating. Regulatory and environmental compliance requirements are equivalent across both parts.

Q: Do the parts require different PCB footprints?

A: No. Both the L4938ED and L4938EDTR-E use the identical 20-SOIC package with 0.295" (7.50mm) width. PCB layout and assembly processes remain unchanged during substitution.

Q: What are the key electrical parameters that define substitution compatibility?

A: Substitution compatibility is determined by: positive output configuration, dual regulator topology, 28V maximum input voltage, 4.9V to 5.1V output voltage range, 0.4V dropout at 100mA and 0.6V dropout at 400mA, Enable and Reset control features, and -40°C to 150°C operating temperature range.

Q: Is the L4938EDTR-E suitable for applications requiring the same current output specifications?

A: Yes. The L4938EDTR-E delivers identical current output ratings of 100mA and 400mA across its dual outputs, matching the L4938ED specifications exactly.