Monolithic Power Systems Inc. MP2492DN-LF

Overview

MP2492DN-LF from Monolithic Power Systems is a monolithic 100kHz step-down DC/DC converter with programmable output current limit, designed for automotive and industrial power supplies requiring wide 4.5V–55V input operation and stable 2A continuous output. It integrates a 0.25Ω internal MOSFET, supports output voltage adjustment from 0.8V to 15V, and implements cycle-by-cycle overcurrent protection and thermal shutdown.

For engineers reviewing the MP2492DN-LF datasheet, MP2492DN-LF pinout, MP2492DN-LF application, or MP2492DN-LF equivalent, this device is selected for high-input-voltage buck regulation where programmable current limiting via ISP/ISN sensing, low-EMI switching, and ceramic-capacitor compatibility are critical design requirements.

Technical Context

The MP2492DN-LF operates in current-mode control with fixed 100kHz frequency and internal slope compensation. Its error amplifier compares FB voltage against a 0.8V reference, while the current sense amplifier monitors VISP–VISN differential (target 100mV) to regulate output current when limit is reached.

It uses bootstrap gate drive (BST–SW) to enable high-side N-channel MOSFET operation, requires external soft-start capacitor on SS, and delivers regulated output via feedback divider while supporting DCR-based or resistor-based current sensing - both validated in typical application schematics.

Key Specifications

Pinout & Package

MP2492DN-LF is packaged in SOIC8E (exposed pad), with pins arranged for high-current path integrity and thermal performance. The exposed pad must be soldered to PCB ground plane for optimal thermal dissipation and noise immunity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2491DN-LF, the MP2492DN-LF delivers 33% higher output current in identical SOIC8E packaging; versus LM5164QDGSRQ1, it provides factory-trimmed 100mV current sense threshold and simplified layout at the expense of AEC-Q100 certification.

Availability

MP2492DN-LF is available at Aetrix Electronics and suitable for USB power supplies, automotive cigarette lighter adapters, and industrial 24V-to-5V conversion requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MP2492DN-LF 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, headquartered in California and serving global industrial, automotive, and consumer markets since 1997.

The MP2492 belongs to MPS's high-voltage buck converter product line, engineered specifically for robust DC/DC regulation in harsh environments-emphasizing wide input range, integrated protection, and ease of implementation in space-constrained designs.

FAQ

What is the maximum duty cycle supported by MP2492DN-LF?

The MP2492DN-LF supports up to ~95% duty cycle, limited by minimum off-time and bootstrap capacitor recharge requirements. At VIN = 50V and VOUT = 15V, the theoretical maximum duty cycle is ~30%; practical maximum occurs at low VIN/VOUT ratios (e.g., 12V→5V yields ~42%). External bootstrap diode is recommended above 65% duty cycle to ensure gate drive stability.

Can MP2492DN-LF operate without an external bootstrap diode?

Yes - the MP2492DN-LF integrates an on-chip bootstrap regulator that charges the BST capacitor from VIN. An external diode (e.g., BAT54) is optional and only recommended for high-duty-cycle operation (>65%), 5V input, or VOUT >12V to improve efficiency and gate drive reliability under sustained high-load conditions.

How is output current limit programmed using DCR sensing?

Using DCR sensing, the current limit is set by the equation I_LIM = 100mV / (DCR × (Ra + Rb)/Rb), where Ra and Rb form a voltage divider between ISP and ISN. Layout must minimize parasitic inductance in the sense path, and DCR tolerance directly impacts limit accuracy - typically ±10% for standard power inductors.

Does MP2492DN-LF support synchronization to an external clock?

No - the MP2492DN-LF features a fixed internal 100kHz oscillator with no external sync input. Frequency variation is ±20% (80–120kHz) over temperature and process; for synchronized multi-rail systems, consider MPS's MPQ4312 or MPQ4361 families which include SYNC pins.

What is the recommended input capacitor value and type?

A 4.7µF X5R or X7R ceramic capacitor placed within 3mm of VIN and GND pins is recommended. For high-transient environments (e.g., automotive), add a 10–22µF bulk capacitor in parallel. Total input capacitance should provide impedance <1Ω at 100kHz to suppress switching noise injection into the source.

Is the exposed pad on MP2492DN-LF electrically connected to GND internally?

Yes - the exposed pad is internally tied to GND and must be soldered to a dedicated PCB ground plane. Thermal resistance θ_JA drops from 50°C/W (no pad connection) to ≤35°C/W with ≥200mm² copper area, directly impacting maximum continuous output current capability at elevated ambient temperatures.

What happens during short-circuit condition at the output?

Under short circuit, the MP2492DN-LF enters hiccup mode: current limit triggers, SS pin is pulled low, converter stops switching, then restarts after thermal recovery delay. This limits average power dissipation and prevents thermal runaway - verified in typical performance curves showing stable 0.5A short-circuit current at 12V input.