Monolithic Power Systems Inc. MP62181DH-LF-P

Overview

MP62181DH-LF-P from Monolithic Power Systems is a single-channel, active-high enable power distribution switch with 2A continuous current capability, 2.8A typical current limit, and integrated thermal shutdown and under-voltage lockout. It uses an internal 75mΩ MOSFET, operates from 2.7V to 5.5V input, and delivers fault-protected USB VBUS power distribution in portable electronics.

For engineers reviewing the MP62181DH-LF-P datasheet, MP62181DH-LF-P pinout, MP62181DH-LF-P application, or MP62181DH-LF-P equivalent, key selection criteria include enable polarity (active high), FLAG deglitch timing (8ms), reverse current blocking, and MSOP8E package thermal performance (θJA = 55°C/W).

Technical Context

The MP62181DH-LF-P implements a precision current-limiting architecture using internal sense-amplifier feedback to enforce a 2.8A trip threshold with ±0.7A tolerance across temperature. Its constant-current mode activates within microseconds of overload onset, limiting energy dissipation during short-circuit events.

Thermal protection engages at 140°C junction temperature with 20°C hysteresis, and UVLO disables operation below 1.95V rising-edge threshold. The open-drain FLAG pin reports over-current or thermal faults after 8ms deglitch filtering-excluding UVLO and over-temperature events from deglitching.

Key Specifications

Pinout & Package

MP62181DH-LF-P is housed in an MSOP8E (3mm × 3mm, 0.65mm pitch) thermally enhanced package with exposed pad soldered to PCB ground for θJA = 55°C/W. Pin 1 is marked by half-circle indentation per JEDEC MO-187 AA-T.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current-limited power distribution switch applications.

Compared with MP62181DH-LF-P, the TPS22965 offers lower conduction loss but adds design complexity for reverse blocking, while the NIS5132 requires signal conditioning for active-high enable-making MP62181DH-LF-P optimal for USB-C and portable systems needing integrated protection and polarity flexibility.

Availability

MP62181DH-LF-P is available at Aetrix Electronics and suitable for smartphone USB switching, notebook ExpressCard protection, and industrial USB hub power management requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle support.

Supply support for MP62181DH-LF-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with core expertise in DC/DC conversion, LED drivers, and load switches.

The MP6218x series targets portable and USB-powered systems requiring robust, integrated power distribution with minimal external components and guaranteed fault response timing.

FAQ

What is the exact enable logic polarity for MP62181DH-LF-P?

The MP62181DH-LF-P features active-high enable: the switch turns on when EN voltage exceeds 2V (min) and turns off when EN falls below 0.8V (max). This differs from the MP62180 variant, which uses active-low enable-confirmed by ordering code suffix "1" and datasheet Figure 2 block diagram.

Does MP62181DH-LF-P support reverse current blocking during disable?

Yes-reverse current leakage is specified at 0.2μA maximum when OUT = 5.5V and IN = GND. This is achieved via internal MOSFET body diode blocking and gate control, eliminating need for external reverse-protection diodes in USB VBUS applications.

How does the FLAG pin behave during UVLO or thermal shutdown?

The FLAG pin is not deglitched during UVLO or thermal events: it asserts immediately upon detection (no 8ms delay). Only over-current faults undergo 8ms deglitch filtering. This allows rapid system-level response to supply or thermal failures while rejecting transient current spikes.

What is the recommended minimum input capacitance for stable operation?

A minimum 10μF ceramic capacitor between IN and GND is required per datasheet Section 9. This suppresses input transients, improves immunity to short-circuit ringing, and ensures reliable UVLO release-verified in typical application circuit on page 1.

Can MP62181DH-LF-P be used in 3.3V-only systems without 5V input capability?

Yes-the device operates across 2.7V to 5.5V, so it functions reliably at 3.3V nominal input. At 3.3V, R_DS(on) increases to ~85mΩ (per Figure 5), yielding ~170mV drop at 2A-still within USB 2.0 VBUS tolerance (4.75–5.25V) when used as a downstream switch.

Is the exposed thermal pad on MSOP8E package electrically connected?

Yes-the exposed pad is internally connected to GND and must be soldered to a PCB ground plane. Datasheet Package Information (page 10) specifies "Exposed Pad on Backside Connect to GND", and thermal resistance values (θJC = 12°C/W) assume this connection for valid junction-to-case cooling.

What is the turn-off time specification under heavy capacitive load?

Turn-off time (T_off) is 10ms maximum when CL = 100μF and RL = 5Ω (Electrical Characteristics table, page 3). This value reflects controlled discharge through internal circuitry-not passive RC decay-and ensures predictable power-down sequencing in USB hot-swap applications.