Microchip Technology MIC24085BYML TR

Overview

MIC24085BYML TR from Micrel is a fixed 1.5V, 3A, 1MHz synchronous buck regulator with integrated high- and low-side MOSFETs in a 16-pin 3mm × 3mm QFN package. It operates from 4.5V to 18V input, delivers ±1.5% output voltage accuracy, and features power-good monitoring, thermal shutdown, and cycle-by-cycle current limiting - used in networking gateways and set-top box power rails.

For engineers reviewing the MIC24085BYML TR datasheet, MIC24085BYML TR pinout, MIC24085BYML TR application, or MIC24085BYML TR equivalent, key selection considerations include its fixed 1.5V output, 10µA shutdown current, internal soft-start timing, PFM light-load mode, and compatibility with ceramic output capacitors without external compensation.

Technical Context

The MIC24085BYML TR uses peak current-mode PWM control with internal slope compensation and fully integrated loop compensation, enabling stable operation with low-ESR ceramic output capacitors. Its fixed 1MHz switching frequency supports compact magnetics and predictable EMI filtering.

It implements frequency foldback during overload (dropping to 250kHz when FB < 0.54V), dual overcurrent protection (cycle-by-cycle limit + foldback), and precise power-good signaling with 93–95% VOUT threshold and 11ms recovery hold time - all operating across –40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

Package: 16-pin 3mm × 3mm QFN (ML) with exposed thermal pad (ePAD), rated for –40°C to +125°C junction temperature. The ePAD must be soldered to PGND for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2315DJ-LF-Z and TPS54332DDAR, the MIC24085BYML TR provides fixed 1.5V regulation with integrated PG, lower shutdown current, and smaller footprint - making it optimal for cost- and space-sensitive applications where output voltage is invariant and system-level fault reporting is essential.

Availability

MIC24085BYML TR is available at Aetrix Electronics and suitable for networking gateways, set-top box SoC rails, and industrial camera modules requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for MIC24085BYML TR 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

Micrel Inc. was a U.S.-based analog and power management semiconductor company acquired by Microchip Technology in 2015; its legacy power products remain widely deployed in industrial and communications infrastructure.

The MIC24085 family was designed as a highly integrated, cost-optimized buck regulator platform targeting space-constrained, high-volume applications such as broadband access equipment and consumer digital video devices.

FAQ

What is the output voltage tolerance of the MIC24085BYML TR under full temperature and load range?

The MIC24085BYML TR delivers a fixed 1.5V output with ±1.5% accuracy over –40°C to +125°C junction temperature and full 0–3A load range. This specification is guaranteed by the internal 0.9V reference (±1.5%) and resistor divider ratio precision inherent to the fixed-output variant - no external calibration is required.

Does the MIC24085BYML TR require external compensation components?

No, the MIC24085BYML TR features fully internal loop compensation optimized for stability with ceramic output capacitors. Unlike adjustable buck regulators, it does not require external RC networks on the COMP or SS pins - simplifying layout and reducing BOM count while maintaining phase margin >45° across operating conditions.

How does the power-good (PG) function behave during startup and fault conditions for the MIC24085BYML TR?

The MIC24085BYML TR asserts PG high after 4ms soft-start when VOUT reaches 93–103% of 1.5V. If VOUT drops below 93%, PG pulls low and remains low for 11ms after recovery - providing clean reset signaling to downstream logic. PG is an open-drain output requiring a pull-up resistor to VOUT.

Can the MIC24085BYML TR operate reliably at its maximum 3A output current in a 65°C ambient environment?

Yes, the MIC24085BYML TR sustains 3A continuous output at 65°C ambient when mounted on a standard 4-layer PCB with the ePAD fully soldered to a 1-in² thermal pad. Its θ_JA = 68°C/W and 170°C thermal shutdown threshold ensure safe operation without derating under these conditions.

What is the purpose of the BST pin on the MIC24085BYML TR, and what capacitor value is required?

The BST pin on the MIC24085BYML TR supplies the bootstrap voltage for the high-side N-channel MOSFET gate driver. A 0.1µF ceramic capacitor must be placed between BST and SW to maintain sufficient gate drive voltage during high-duty-cycle operation - failure to install this capacitor will cause high-side FET failure and loss of regulation.