Microchip Technology MIC37120-1.8YMT-TR

Overview

MIC37120-1.8YMT-TR from Micrel is a fixed-output 1.8V, 1A low-dropout linear regulator in a 2mm × 2mm Thin MLF-6L package, featuring 230mV typical dropout at full load, ±2% initial output voltage accuracy, and integrated output auto-discharge circuitry-designed for noise-sensitive power rails in portable multimedia devices and embedded systems.

For engineers reviewing the MIC37120-1.8YMT-TR datasheet, MIC37120-1.8YMT-TR pinout, MIC37120-1.8YMT-TR application, or MIC37120-1.8YMT-TR equivalent, key selection considerations include its 2.375V–5.5V input range, 2.2µF ceramic capacitor stability, 60dB+ PSRR up to 1kHz, thermal shutdown protection, and enable-controlled shutdown with sub-5µA quiescent current.

Technical Context

The MIC37120-1.8YMT-TR implements a CMOS-based LDO architecture with internal reference, error amplifier, and pass transistor optimized for low-noise operation. Its output auto-discharge function actively pulls the OUT pin to GND when EN is low, preventing residual voltage hold-up on downstream loads.

It operates across −40°C to +125°C junction temperature, supports stable regulation with only 2.2µF ceramic output capacitance, and maintains 2% output accuracy over line, load, and temperature-enabling reliable use in battery-powered and thermally constrained applications without external compensation.

Key Specifications

Pinout & Package

Package: 2mm × 2mm Thin MLF-6L, exposed thermal pad (pin 2), RoHS-compliant with high-melting solder exemption.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MIC37120-1.8YM, the MIC37120-1.8YMT-TR offers superior thermal dissipation per unit area due to its exposed pad, while compared with XC6210B182MR-G, it provides guaranteed auto-discharge behavior critical for system-level power sequencing and leakage control.

Availability

MIC37120-1.8YMT-TR is available at Aetrix Electronics and suitable for mobile multimedia power, point-of-load regulation, gaming console core rails, and portable GPS receiver supply requiring stable component supply and long-term production continuity.

Supply support for MIC37120-1.8YMT-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 semiconductor company specializing in high-performance analog and mixed-signal ICs, acquired by Microchip Technology in 2015.

The MIC371xx family was designed specifically for low-noise, high-PSRR, 1A LDO applications in consumer electronics-emphasizing compact packaging, minimal external components, and robust protection features for battery-powered and thermally constrained systems.

FAQ

What is the minimum input voltage required for MIC37120-1.8YMT-TR to regulate 1.8V output?

The MIC37120-1.8YMT-TR requires a minimum input voltage of 2.375V to maintain regulation. At 1A load, its typical dropout is 230mV, meaning VIN must be ≥2.03V-but the absolute minimum specified input is 2.375V per datasheet operating ratings. Below this, UVLO disables regulation. The MIC37120-1.8YMT-TR will not operate reliably below 2.375V input regardless of load.

Does MIC37120-1.8YMT-TR require an external resistor network for 1.8V output?

No. The MIC37120-1.8YMT-TR is a fixed-output variant-its 1.8V regulation is achieved internally without external resistors. Unlike the adjustable MIC37122 variants, it uses an internal feedback divider. The SNS pin enables remote sensing but does not alter the nominal output voltage. No external components are needed to set the 1.8V output of the MIC37120-1.8YMT-TR.

How does the output auto-discharge feature work in MIC37120-1.8YMT-TR?

When the EN pin is driven low, the MIC37120-1.8YMT-TR activates an internal ~30Ω NMOS switch between OUT and GND, actively discharging the output capacitor. This eliminates reliance on external bleed resistors and ensures rapid rail collapse-critical for power sequencing and leakage control. The discharge path is only active during shutdown; it is fully disabled during normal operation. This behavior is exclusive to MIC37120/MIC37122 variants, not present in MIC37110/MIC37112.

Can MIC37120-1.8YMT-TR be used with a 10µF output capacitor?

Yes. While the MIC37120-1.8YMT-TR is stable with a minimum 2.2µF ceramic output capacitor, using a 10µF X7R/X5R ceramic capacitor improves transient response and high-frequency noise suppression. Ultra-low ESR types are recommended for ≥10µF values. Larger capacitance does not compromise stability-it enhances performance in dynamic load scenarios such as processor burst mode, and remains fully compatible with the MIC37120-1.8YMT-TR's internal compensation.

What is the thermal resistance (θJA) of MIC37120-1.8YMT-TR, and how does PCB layout affect it?

The MIC37120-1.8YMT-TR has a nominal θJA of 100°C/W under standard JEDEC test conditions-but actual performance depends heavily on PCB layout. The exposed thermal pad (Pin 2) must be soldered to a solid copper ground plane; increasing copper area reduces θJA significantly. For example, 160mm² of 1oz copper can lower effective θJA to ~60°C/W. Without proper thermal pad connection, θJA degrades sharply, risking thermal shutdown at 1A load. Layout directly determines real-world thermal capability of the MIC37120-1.8YMT-TR.