Microchip Technology MIC5239-3.0BM

Overview

MIC5239-3.0BM from Microchip Technology is a 3.0 V fixed-output, high-accuracy low-dropout (LDO) linear regulator with 500 mA output current capability, 340 mV dropout voltage at full load, and ±2% output voltage tolerance. It operates from 4.5 V to 26 V input and delivers stable power to microcontrollers, sensors, and analog circuitry in industrial control modules.

For engineers reviewing the MIC5239-3.0BM datasheet, MIC5239-3.0BM pinout, MIC5239-3.0BM application, or MIC5239-3.0BM equivalent, key selection criteria include dropout voltage under load, thermal shutdown behavior, reverse-current protection, and SOIC-8 package compatibility with PCB layout constraints for thermally demanding environments.

Technical Context

The MIC5239-3.0BM integrates a PNP pass transistor with internal current limiting and thermal foldback, enabling robust operation without external components. Its quiescent current remains stable at 130 µA across input voltages and load conditions, supporting battery-powered systems requiring low standby power.

It features active-low enable control, built-in short-circuit protection with automatic recovery, and no external capacitor required for stability-compatible with ceramic output capacitors as low as 1.0 µF. The device is not current-limited in dropout mode, maintaining regulation until VIN drops below VOUT + VDO.

Key Specifications

Pinout & Package

Supplied in an 8-pin SOIC package with exposed thermal pad (SOIC-8 EP), the MIC5239-3.0BM uses standard SOIC footprint but requires soldering the thermal pad to a PCB copper pour for rated 500 mA operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-3002E/MB and TPS7A4701RGWR, the MIC5239-3.0BM offers optimal balance of 500 mA capability, 340 mV dropout, SOIC-8 thermal performance, and fixed 3.0 V output-making it ideal for industrial and automotive modules where layout simplicity and thermal reliability are prioritized over adjustability or ultra-small size.

Availability

MIC5239-3.0BM is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and medical sensor interfaces requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for MIC5239-3.0BM 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 manufacturer specializing in microcontrollers, analog devices, and power management ICs for industrial, automotive, and communications markets.

The MIC5239 series was designed as a family of high-current, low-dropout regulators targeting thermally demanding embedded systems where reliability under sustained load and input voltage variation is critical.

FAQ

What is the minimum input voltage required for MIC5239-3.0BM to maintain regulation?

The MIC5239-3.0BM maintains regulation as long as the input voltage remains above the sum of its 3.0 V output and its specified dropout voltage. At 500 mA load, dropout is 340 mV, so minimum VIN is 3.34 V. However, the device's absolute minimum input rating is 4.5 V per datasheet-operation below that risks internal circuit malfunction regardless of dropout margin. Always respect the 4.5 V minimum.

Does MIC5239-3.0BM require an external output capacitor, and what type is recommended?

Yes, MIC5239-3.0BM requires an external output capacitor for stability. The datasheet specifies a minimum of 1.0 µF ceramic capacitor with ESR less than 100 mΩ. Tantalum or aluminum electrolytic capacitors are not recommended due to higher ESR and potential instability. X5R or X7R dielectrics are preferred for temperature stability across –40°C to +125°C operation.

Can MIC5239-3.0BM be used in parallel to increase output current?

No, MIC5239-3.0BM is not designed for parallel operation. Its internal PNP pass transistor lacks current-sharing circuitry, and mismatched dropout voltages between units would cause uneven load distribution and possible thermal runaway. For higher current needs, select a single higher-rated LDO such as MIC5239-3.0BM's 1 A counterparts or use a discrete MOSFET-based current-sharing design.

Is the exposed thermal pad (EP) on MIC5239-3.0BM electrically connected, and how should it be handled on the PCB?

Yes, the exposed thermal pad on MIC5239-3.0BM is internally connected to GND. It must be soldered to a dedicated GND copper pour on the PCB, with at least four thermal vias (0.3 mm diameter) connecting to inner or bottom-layer GND planes. Leaving the pad unconnected degrades thermal resistance by >50%, risking premature thermal shutdown at loads above 250 mA.

What protection features does MIC5239-3.0BM include, and how do they behave during fault conditions?

MIC5239-3.0BM includes thermal shutdown with 20°C hysteresis, current limiting with foldback, reverse-current protection, and short-circuit protection with automatic recovery. During overload, current limit activates first (~650 mA); if sustained, junction temperature rises and thermal shutdown engages at 160°C. After cooling to 140°C, the device resumes normal operation without manual reset.