Monolithic Power Systems Inc. MPQ2560DN-LF-Z

Overview

MPQ2560DN-LF-Z from Monolithic Power Systems is an industrial-grade, non-synchronous step-down DC/DC converter with integrated 220mΩ high-side MOSFET, delivering up to 2.5A output current across a 4.5V–42V input range and adjustable 0.8V–39V output. It operates at up to 4MHz switching frequency, features programmable frequency via external resistor, and includes internal soft-start, thermal shutdown, and UVLO for automotive and industrial power rails.

For engineers reviewing the MPQ2560DN-LF-Z datasheet, MPQ2560DN-LF-Z pinout, MPQ2560DN-LF-Z application, or MPQ2560DN-LF-Z equivalent, key selection criteria include its 4MHz EMI-suppressing capability, 12μA shutdown quiescent current for battery systems, 2.5A current limit without external sense resistor, and SOIC8E thermally enhanced package with exposed pad.

Technical Context

The MPQ2560DN-LF-Z uses current-mode control with cycle-by-cycle peak current limiting and internal transconductance error amplifier (G_CS = 8 A/V, G_EA = 60 μA/V). Its oscillator frequency is set by an external resistor on the FREQ pin, supporting 1.55–4.85 MHz operation, and it implements frequency foldback at light load to maintain efficiency.

It integrates a bootstrap driver for the high-side MOSFET, requiring external BST–SW capacitor charging during SW low phase; internal UVLO (3.0V rising, 2.6V falling) and thermal shutdown (150°C trip, 135°C hysteresis) ensure fault-tolerant operation in harsh environments.

Key Specifications

Pinout & Package

MPQ2560DN-LF-Z is housed in a thermally enhanced SOIC-8 package (SOIC8E) with exposed thermal pad on underside, rated at θ_JA = 50°C/W and θ_JC = 10°C/W on JEDEC 4-layer board. The exposed pad must be soldered to PCB ground plane for optimal thermal performance and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ2560DN-LF-Z, the QFN variant offers superior thermal resistance and miniaturization but demands advanced assembly; the MP2560DN-LF-Z sacrifices industrial temperature qualification for lower unit cost without altering functionality.

Availability

MPQ2560DN-LF-Z is available at Aetrix Electronics and suitable for industrial PLC power rails, automotive body control modules, and distributed battery-powered sensors requiring stable component supply across extended temperature and voltage ranges.

Supply support for MPQ2560DN-LF-Z 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 motor control solutions.

The MPQ2560 belongs to MPS's industrial-grade buck converter product line, designed specifically for ruggedized power delivery in automotive, factory automation, and infrastructure applications demanding wide VIN, high reliability, and compact footprint.

FAQ

What is the maximum recommended output current for MPQ2560DN-LF-Z in SOIC8E package at 85°C ambient?

The device delivers up to 2.5A output current under typical conditions, but thermal limits constrain continuous operation. With θ_JA = 50°C/W and T_J(MAX) = 125°C, maximum allowable power dissipation at 85°C ambient is 0.8W. At 12V input and 3.3V output, this supports ~1.8A continuous load with proper PCB copper area and airflow. Derating is required above 60°C ambient without forced cooling.

Can MPQ2560DN-LF-Z operate with 100% duty cycle?

No. The MPQ2560DN-LF-Z has a minimum off-time specification of 100ns, preventing true 100% duty cycle operation. This limitation ensures reliable bootstrap capacitor recharge and prevents loss of high-side gate drive. For applications requiring near-100% duty, a synchronous buck or external driver solution is necessary.

Is an external Schottky diode mandatory, and what are key selection criteria?

Yes - the MPQ2560DN-LF-Z is non-synchronous and requires an external Schottky diode. Key criteria: reverse voltage rating >42V (e.g., 80V), forward current rating >2.5A, low forward voltage (<0.5V at 2.5A), and fast recovery (<50ns). Diodes like Diodes Inc. B380-13-F meet these requirements and minimize conduction loss.

How does frequency foldback improve light-load efficiency?

At light loads, the MPQ2560DN-LF-Z reduces switching frequency to lower gate-driving and switching losses. This dynamic scaling maintains >80% efficiency down to 10mA load - critical for always-on industrial sensors. Foldback is automatic and requires no external control; it activates below ~15% of full load.

What is the purpose of the BST capacitor, and what value is recommended?

The BST capacitor (typically 0.1μF X7R ceramic) forms a charge pump that supplies the floating gate driver for the high-side MOSFET. It must be placed directly between BST and SW pins with minimal trace length. Insufficient capacitance causes gate underdrive, increased R_DS(on), and thermal runaway - especially at high duty cycles.

Does MPQ2560DN-LF-Z support output voltages below 0.8V?

No. The internal feedback reference is fixed at 0.8V ±3%, and the FB pin is designed for resistive divider-based scaling only. Output voltages below 0.8V cannot be achieved without external circuitry (e.g., op-amp reference injection), which voids guaranteed specifications and stability.

How is thermal shutdown behavior implemented during overload?

When junction temperature exceeds 150°C, the MPQ2560DN-LF-Z disables the high-side switch and pulls COMP low. After temperature drops to 135°C (15°C hysteresis), it automatically recovers without requiring EN toggle. This hiccup-mode protection prevents latch-up and enables self-recovery after transient overloads.