MCP1812AT-040/LB Equivalent & Substitute Parts

Part Overview

The MCP1812AT-040/LB is a linear voltage regulator IC from Microchip Technology designed for positive fixed 4V output at 300mA in SC-70-3 surface mount packaging. This device is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity. The regulator features enable control and over-current protection, suitable for low-power applications requiring stable 4V regulation from input sources up to 5.5V.

Substiute Parts

MCP1812AT-040/LB

Microchip TechnologyIn Stock: 774MCP1812AT-040/LB Datasheet

Current PartRFQ

MIC5504-3.3YM5-TR

Microchip TechnologyIn Stock: 18322MIC5504-3.3YM5-TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MCP1812AT-040/LB is determined by the following critical parameters:

• Output Voltage: The fixed output voltage of 4V is the primary functional requirement. Substitute parts must deliver the same regulated voltage level.
• Output Current Capability: Minimum 300mA output current is required to maintain load support equivalent to the original design.
• Input Voltage Range: Maximum input voltage of 5.5V establishes the upper operating boundary; substitutes must accept this range.
• Voltage Dropout: Maximum dropout of 0.6V @ 300mA defines the minimum input-to-output differential required for proper regulation.
• Control and Protection Features: Enable functionality and over-current protection are mandatory for system compatibility.
• Mounting and Package Compatibility: Surface mount technology with compatible pinout and thermal characteristics.

The MIC5504-3.3YM5-TR does not meet the primary substitution criterion of matching the 4V fixed output voltage (it provides 3.3V output). Therefore, this part cannot serve as a direct functional equivalent for applications requiring 4V regulation. Substitution would require circuit redesign or voltage level adjustment in dependent circuitry.

Parameter Comparison

Engineering Selection Recommendations

The MIC5504-3.3YM5-TR is not recommended as a direct substitute for the MCP1812AT-040/LB due to the fundamental output voltage mismatch (3.3V vs. 4V). Direct substitution would result in under-voltage delivery to dependent circuitry designed for 4V operation.

However, the MIC5504-3.3YM5-TR offers advantages in active product status, extended operating temperature range (-40°C ~ 125°C vs. -40°C ~ 85°C), enhanced protection features including over-temperature monitoring, and superior voltage dropout performance (0.38V vs. 0.6V). These characteristics make it suitable for new designs or redesigned applications where 3.3V regulation is acceptable.

For applications requiring 4V output equivalent to the MCP1812AT-040/LB, alternative linear regulators with matching output voltage specifications from Microchip Technology or other manufacturers should be evaluated.

Frequently Asked Questions (FAQ)

Q: Can the MIC5504-3.3YM5-TR replace the MCP1812AT-040/LB in existing designs?

A: No. The MIC5504-3.3YM5-TR outputs 3.3V while the MCP1812AT-040/LB outputs 4V. Direct substitution would cause voltage-dependent circuits to malfunction. Circuit redesign is required if this substitute is used.

Q: What is the primary reason these parts are not interchangeable?

A: Output voltage specification is the critical parameter. The MCP1812AT-040/LB provides fixed 4V regulation, while the MIC5504-3.3YM5-TR provides fixed 3.3V regulation. These are distinct voltage classes with different application requirements.

Q: Are the package types compatible?

A: No. The MCP1812AT-040/LB uses SC-70-3 (SOT-323) packaging with 3 pins, while the MIC5504-3.3YM5-TR uses SOT-23-5 packaging with 5 pins. Pinout and footprint differences prevent direct board-level substitution.

Q: Does the MIC5504-3.3YM5-TR offer any performance advantages?

A: Yes. The MIC5504-3.3YM5-TR features lower voltage dropout (0.38V vs. 0.6V), extended operating temperature range (to 125°C), and additional over-temperature protection. However, these advantages are only relevant if the 3.3V output voltage is acceptable for the application.

Q: Why is the MCP1812AT-040/LB classified as obsolete?

A: Microchip Technology has discontinued this product line. The MIC5504 series represents the active product family for similar low-current linear regulation applications, though with different output voltage options.

Q: What should be done if a 4V regulator equivalent is needed?

A: Evaluate alternative linear regulators from Microchip Technology or other manufacturers that specify 4V fixed output with 300mA capability and compatible package options for your application requirements.