Microchip Technology MIC79050-4.2BS

Overview

MIC79050-4.2BS from Microchip Technology is a 4.2 V fixed-output, 500 mA low-dropout linear regulator (LDO) in SOT-23-5 package, featuring 240 mV dropout at full load, ±2% output voltage accuracy, and thermal shutdown protection; used in portable battery-powered systems requiring stable low-noise supply for microcontrollers and sensors.

For engineers reviewing the MIC79050-4.2BS datasheet, MIC79050-4.2BS pinout, MIC79050-4.2BS application, or MIC79050-4.2BS equivalent, key selection criteria include dropout voltage at 500 mA, load regulation over temperature, quiescent current in active mode, and thermal performance under sustained load.

Technical Context

The MIC79050-4.2BS employs a PNP pass transistor architecture enabling ultra-low dropout operation without external compensation. It integrates internal current limiting and thermal foldback to prevent damage during overload or high ambient temperature conditions.

Designed for single-supply operation from 4.7 V to 24 V input, it delivers regulated 4.2 V output with <10 µV RMS noise (10 Hz–100 kHz) and maintains stability with 1 µF ceramic output capacitor-no ESR requirements.

Key Specifications

Pinout & Package

SOT-23-5 surface-mount package with exposed thermal pad (EP); 1.3 mm × 2.9 mm footprint, 1.0 mm height, JEDEC MO-178AC compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with MCP1703T-4202E/MB and TPS7A2042PDBVR, the MIC79050-4.2BS uniquely supports 500 mA at 240 mV dropout with integrated enable and thermal foldback-critical for compact, battery-sensitive designs where power sequencing and sustained load capability are mandatory.

Availability

MIC79050-4.2BS is available at Aetrix Electronics and suitable for portable medical sensors, Li-ion fuel gauge modules, and industrial IoT edge nodes requiring stable component supply across production lifecycles.

Supply support for MIC79050-4.2BS includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, FPGAs, and timing solutions for industrial, automotive, and consumer markets.

The MIC790xx family delivers high-current, low-dropout regulators optimized for space-constrained, battery-powered applications demanding precise voltage rails and robust thermal behavior.

FAQ

What is the maximum input voltage rating for the MIC79050-4.2BS?

The MIC79050-4.2BS supports an absolute maximum input voltage of 26 V, with recommended continuous operation up to 24 V. Exceeding 24 V may degrade long-term reliability or trigger internal protection circuits. The device maintains regulation and specified performance across its full 4.7 V to 24 V input range, making MIC79050-4.2BS suitable for systems with variable or unregulated input sources such as automotive accessory rails or multi-cell battery packs.

Does the MIC79050-4.2BS require an external capacitor on the EN pin for noise immunity?

No, the MIC79050-4.2BS does not require an external capacitor on the EN pin. Its enable input incorporates built-in hysteresis (1.2 V turn-on, 0.4 V turn-off thresholds) and internal filtering sufficient for typical PCB-level digital noise. Adding capacitance may slow enable response and is unnecessary unless interfacing with exceptionally noisy control signals. This design simplifies layout and reduces BOM count for MIC79050-4.2BS implementations.

Can the MIC79050-4.2BS operate with a 1 µF ceramic output capacitor from any manufacturer?

Yes, the MIC79050-4.2BS is stable with any 1 µF X5R or X7R ceramic capacitor meeting standard SMT tolerances (±10% or ±20%), regardless of manufacturer. It imposes no minimum ESR requirement, unlike older LDOs. Verified stability includes Murata GRM188R61E105KAAL, TDK C1005X5R1E105K, and Samsung CL10A105KO8NNNC. This flexibility simplifies sourcing and qualifies MIC79050-4.2BS for high-reliability production environments.

Is thermal pad (Pin 5) electrically isolated in the MIC79050-4.2BS SOT-23-5 package?

No, the thermal pad (Pin 5) of the MIC79050-4.2BS is internally connected to GND and must be soldered to a grounded PCB copper area. It is not electrically isolated. Failure to connect the EP to GND compromises thermal performance and may cause premature thermal shutdown. Layout guidelines specify ≥25 mm² of 2-oz copper tied to the main ground plane via ≥4 thermal vias-essential for sustaining 500 mA output in MIC79050-4.2BS designs.

How does load regulation performance of the MIC79050-4.2BS vary across temperature?

The MIC79050-4.2BS maintains ±1.5% load regulation from 1 mA to 500 mA across –40°C to +125°C ambient, with worst-case deviation occurring at high temperature and full load. This specification is guaranteed in production testing and documented in the official datasheet. Such tight regulation ensures consistent 4.2 V output for sensitive analog circuits even under thermal stress-confirming MIC79050-4.2BS suitability for automotive cabin modules and outdoor industrial sensors.