Monolithic Power Systems Inc. MPQ2178GQHE-11-AEC1-P

Overview

MPQ2178GQHE-11-AEC1-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified, synchronous step-down DC/DC converter delivering 2A continuous output at fixed 1.1V with 1.089–1.111V regulation accuracy, 2.4MHz switching frequency, and integrated 70mΩ/40mΩ power MOSFETs. It operates across 2.5V–6V input, supports 100% duty cycle, and integrates power good (PG), soft start (SS), output discharge, and over-voltage protection - deployed in automotive clusters and telematics power rails.

For engineers reviewing the MPQ2178GQHE-11-AEC1-P datasheet, MPQ2178GQHE-11-AEC1-P pinout, MPQ2178GQHE-11-AEC1-P application, or MPQ2178GQHE-11-AEC1-P equivalent, key selection criteria include its wettable-flank QFN-8 package for automated optical inspection, COT control for fast transient response, -40°C to +150°C junction temperature rating, and functional safety documentation under MPSafe™ QM.

Technical Context

The MPQ2178GQHE-11-AEC1-P implements constant-on-time (COT) control with VIN feed-forward to maintain stable 2.4MHz switching across 2.5V–6V input and full load range, eliminating external compensation. Its internal P-channel (70mΩ) and N-channel (40mΩ) MOSFETs enable high-efficiency 2A operation down to 1.1V output with 1% FB reference accuracy (600mV ±6mV).

Fault management includes cycle-by-cycle current limiting (PCH peak: 3.5A typ, NCH valley: 2A typ), thermal shutdown at 170°C, hiccup-mode short-circuit protection, and output over-voltage protection triggered at 115% of VFB with 2µs delay. PG asserts high when VFB exceeds 90% of VREF and sinks ≥1mA at 0.4V when pulled low.

Key Specifications

Pinout & Package

MPQ2178GQHE-11-AEC1-P uses a wettable-flank QFN-8 package (1.5mm × 2mm, 0.5mm pitch) with exposed thermal pad for enhanced thermal dissipation in space-constrained automotive PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with MPQ2178GQHE-11-AEC1-P, the -12 variant offers identical reliability and footprint but mismatched output voltage, while the TPS6286418RTER trades automotive qualification and 1.1V precision for higher current and speed - neither serves as a direct replacement without electrical or qualification revalidation.

Availability

MPQ2178GQHE-11-AEC1-P is available at Aetrix Electronics and suitable for automotive cluster displays, ADAS camera modules, telematics control units, and key fob transceivers requiring stable component supply with AEC-Q100 compliance and long-term production continuity.

Supply support for MPQ2178GQHE-11-AEC1-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 power management ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ2178 belongs to MPS's automotive-grade MPQ series, engineered specifically for demanding automotive subsystems requiring AEC-Q100 qualification, extended temperature operation, and functional safety documentation (MPSafe™ QM).

FAQ

What is the purpose of the SS pin on MPQ2178GQHE-11-AEC1-P?

The SS (soft-start) pin controls the VOUT ramp-up time using an external capacitor. For this fixed-1.1V variant, the internal SS charge current is 3µA; a 1nF minimum capacitor yields ~0.2ms soft-start time, limiting inrush current during power-up and preventing output overshoot in sensitive automotive loads.

Can MPQ2178GQHE-11-AEC1-P operate with input voltage below 2.5V?

No. The absolute minimum input voltage is 2.5V per datasheet specifications. Below this, UVLO activates - the rising threshold is 2.45V with 200mV hysteresis - and the device remains disabled. This ensures reliable startup during automotive cold-crank conditions where battery voltage may dip to ~2.5V.

Does MPQ2178GQHE-11-AEC1-P support pre-biased output startup?

Yes. The device supports pre-biased startup: when EN is asserted, it safely ramps VOUT from any existing pre-charged voltage (e.g., residual charge on output cap) without causing reverse current or latch-up, a critical feature for multi-rail automotive systems with staggered power sequencing.

How is power good (PG) functionality implemented?

PG is an open-drain output that pulls high (via external pull-up) when VFB ≥ 90% of 600mV reference, indicating valid regulation. It pulls low (<0.4V at 1mA sink) when VFB drops below 85% of VREF, signaling undervoltage or fault. PG remains active during 100% duty cycle operation.

What thermal performance can be expected in a typical 4-layer PCB layout?

On a JEDEC-standard 4-layer board (EVQ2178-QH-00A), θJA is 59°C/W. At 2A load and 5V input, typical power loss is ~0.3W, resulting in ~17.7°C rise above ambient - well within the -40°C to +150°C junction limit, even at +85°C ambient.

Is the FB pin used in the fixed-output MPQ2178GQHE-11-AEC1-P variant?

No. In fixed-output versions like MPQ2178GQHE-11-AEC1-P, the feedback divider is internal; the FB pin is internally connected and must be left floating. Connecting external components to FB will disrupt regulation and is not permitted per datasheet guidance.

What protection features are active during short-circuit events?

Upon short-circuit detection (VOUT falling below OV threshold), the device enters hiccup-mode protection: it shuts down for ~10ms, then attempts restart. This limits average power dissipation and prevents thermal runaway while maintaining visibility via PG deassertion and SW node activity.