Microchip Technology MIC5371-SPYMT-TR

Overview

MIC5371-SPYMT-TR from Micrel is a dual-channel, high-accuracy, low-dropout linear regulator IC delivering independent 150mA outputs at 3.3V and 3.0V. It features ±2% initial output voltage accuracy, 155mV dropout at full load, and ultra-low 32µA quiescent current per LDO - optimized for space-constrained, battery-powered portable electronics such as camera phones and GPS handhelds.

For engineers reviewing the MIC5371-SPYMT-TR datasheet, MIC5371-SPYMT-TR pinout, MIC5371-SPYMT-TR application, or MIC5371-SPYMT-TR equivalent, key selection considerations include its auto-discharge function (30Ω internal NFET), independent active-high enable pins, stable operation with 1µF ceramic capacitors, and operation across –40°C to +125°C junction temperature.

Technical Context

The MIC5371-SPYMT-TR integrates two fully independent CMOS-based LDO regulators sharing only VIN and GND. Each channel includes dedicated EN1/EN2 inputs, enabling selective power sequencing and zero-off-mode shutdown with <1µA total ground current when both regulators are disabled.

Unlike the MIC5370 variant, the MIC5371-SPYMT-TR incorporates an integrated auto-discharge circuit activated upon disable - applying a 30Ω resistive load between VOUT1/VOUT2 and GND to rapidly deplete output capacitance. This eliminates residual voltage hold-up in multi-rail systems requiring strict power-down timing control.

Key Specifications

Pinout & Package

Package: 6-pin 1.6mm × 1.6mm Thin MLF® (MT) with exposed thermal pad (internally connected to GND). RoHS-compliant, halogen-free mold compound, NiPdAu lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MIC5370-SPYMT-TR, the MIC5371-SPYMT-TR adds mandatory auto-discharge for fail-safe power-down, while the Torex XC6216D333MR-G offers lower dropout but sacrifices dual-output integration and thermal performance in the same 1.6mm × 1.6mm footprint.

Availability

MIC5371-SPYMT-TR is available at Aetrix Electronics and suitable for camera phone power management, GPS handheld dual-rail supply, and portable media player core/IO rail applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MIC5371-SPYMT-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 analog, power management, and timing solutions before its acquisition by Microchip Technology in 2015. Its LDO portfolio emphasized miniaturization, low IQ, and robust protection features.

The MIC5371-SPYMT-TR belongs to Micrel's high-performance dual-LDO family designed specifically for space-constrained, battery-powered portable electronics requiring independent rail control, fast transient response, and guaranteed power-down behavior.

FAQ

What is the auto-discharge function of the MIC5371-SPYMT-TR, and how does it operate?

The MIC5371-SPYMT-TR integrates an internal 30Ω NFET between each output and GND, activated automatically when its respective enable pin (EN1 or EN2) is driven low. This discharges external output capacitors rapidly - for example, reducing 3.3V across a 10µF cap to <0.5V in under 200µs. This eliminates residual voltage that could cause latch-up or violate power-down timing in camera modules or GPS receivers, and removes the need for external bleed resistors.

Can the MIC5371-SPYMT-TR operate with input voltages below 2.5V?

No. The MIC5371-SPYMT-TR has a specified operating input voltage range of +2.5V to +5.5V. Below 2.5V, regulation is not guaranteed - dropout voltage increases nonlinearly, and internal reference and bias circuits may cease functioning. For Li-ion batteries nearing end-of-discharge (<2.8V), the 155mV dropout allows continued operation down to ~2.85V on the 3.0V rail, but operation below 2.5V violates absolute maximum ratings and risks functional failure.

What is the thermal performance of the MIC5371-SPYMT-TR in its 1.6mm × 1.6mm Thin MLF® package?

The MIC5371-SPYMT-TR has a junction-to-ambient thermal resistance (θJA) of 90°C/W in the standard 1.6mm × 1.6mm Thin MLF® package. At full 150mA load on both outputs with 3.6V input and 3.3V/3.0V outputs, power dissipation is ~0.39W, limiting maximum ambient temperature to ~90°C. PCB layout with ≥200mm² of 2oz copper connected to the EPAD is required to maintain safe junction temperatures below the 125°C limit.

Does the MIC5371-SPYMT-TR require external compensation components?

No. The MIC5371-SPYMT-TR is internally compensated and stable with only a 1µF ceramic output capacitor per rail - no external resistors, capacitors, or ESR requirements. X5R or X7R dielectric types are recommended; Y5V dielectrics are discouraged due to excessive capacitance loss over temperature. Input also requires a 1µF ceramic capacitor to GND, placed within 2mm of VIN and GND pins.

How does the MIC5371-SPYMT-TR handle enable pin floating conditions?

The MIC5371-SPYMT-TR EN1 and EN2 pins use CMOS input structure and must never be left floating - doing so may result in indeterminate output states or unintended regulator activation. Each enable pin must be actively driven high (≥1.2V) to enable its LDO or pulled low (≤0.2V) to disable it. If controlled by an open-drain MCU GPIO, a pull-down resistor ≤100kΩ is required to ensure reliable disable state during reset or firmware initialization.