Monolithic Power Systems Inc. MP2488DN-LF-Z

Overview

MP2488DN-LF-Z from Monolithic Power Systems is a fixed-frequency, peak-current-mode step-down LED driver IC integrating a 220mΩ high-side 55V MOSFET and delivering up to 2A constant current to high-power LED strings. It operates from 4.5V to 55V input, features 200mV FB reference for precise current regulation, programmable switching frequency up to 200kHz via external resistor, and 130µA quiescent current in active operation. Used in automotive headlamp modules requiring stable thermal performance and EMI control.

For engineers reviewing the MP2488DN-LF-Z datasheet, MP2488DN-LF-Z pinout, MP2488DN-LF-Z application, or MP2488DN-LF-Z equivalent, key selection criteria include its 2A output capability with internal MOSFET, SOIC8E package with exposed pad for thermal management, 200mV feedback threshold enabling low-loss current sensing, and programmable frequency for EMI-sensitive lighting systems.

Technical Context

The MP2488DN-LF-Z implements peak-current-mode control with a 200mV internal reference voltage applied to the FB pin, enabling accurate LED current regulation using a single external sense resistor. Its error amplifier delivers 400V/V gain and 350µA/V transconductance, with COMP pin clamped between 0.9V and 2.0V during normal operation.

Switching frequency is set by an external resistor (RFREQ) from FREQ to GND, supporting 150–250kHz range; at 495kΩ, it achieves 200kHz. The integrated high-side MOSFET has 220mΩ RDS(ON), 3.2A current limit, and bootstrap-driven gate control with dedicated BST pin and internal 4V bootstrap regulator.

Key Specifications

Pinout & Package

The MP2488DN-LF-Z is housed in an SOIC-8 with exposed thermal pad (SOIC8E), optimized for PCB heat dissipation in high-current LED drivers.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with LT3474EMS#PBF and TPS92630QPWPRQ1, the MP2488DN-LF-Z offers programmable frequency for EMI tailoring, SOIC8E thermal performance at 2A, and analog-only control-making it optimal for cost-sensitive, thermally demanding, non-safety-critical LED lighting where design simplicity and layout flexibility are prioritized.

Availability

MP2488DN-LF-Z is available at Aetrix Electronics and suitable for automotive headlamps, industrial high-bay fixtures, outdoor streetlights, and UV-C disinfection systems requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for MP2488DN-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.

The MP2488 product line targets high-efficiency, high-reliability LED lighting applications in automotive, industrial, and infrastructure markets, emphasizing integration, thermal robustness, and EMI resilience in compact packages.

FAQ

What is the maximum continuous LED current supported by MP2488DN-LF-Z?

The MP2488DN-LF-Z supports up to 2A continuous LED current under proper thermal conditions. This is limited by the internal MOSFET's 3.2A current limit and the SOIC8E package's 2.5W power dissipation rating at +25°C ambient. At 2A output with 12V input, typical efficiency exceeds 95%, keeping junction temperature within safe limits when the exposed pad is properly soldered to a ≥2 cm² copper area.

Can MP2488DN-LF-Z drive LEDs with a total forward voltage exceeding 40V?

Yes. With a 55V maximum input rating and typical 2V dropout across the internal MOSFET and Schottky diode, the MP2488DN-LF-Z can drive LED strings with total forward voltage up to approximately 50V. For example, driving 15× 3.3V white LEDs (49.5V VF) is feasible from a 52V input rail, provided inductor saturation current and diode reverse voltage ratings are appropriately selected.

How is switching frequency programmed, and what resistor value sets 200kHz?

Switching frequency is set by connecting a resistor (RFREQ) from the FREQ pin to GND. Per the datasheet equation RFREQ(kΩ) = 100000/fS(kHz) − 5, a 495kΩ resistor yields 200kHz. A 1nF ceramic capacitor (CFREQ) must be placed in parallel with RFREQ to suppress noise coupling into the oscillator node and ensure stable frequency operation.

Does MP2488DN-LF-Z support PWM dimming, and how is it implemented?

Yes, PWM dimming is supported via the EN pin. Applying a logic-level PWM signal (0–5V) directly to EN enables direct on/off control of the LED current with no color shift. The device features fast turn-on (<50µs) and turn-off (<10µs) times, and internal soft-start ensures no current overshoot at each PWM edge. No external circuitry is required beyond standard level-shifting if the PWM source is not 5V-tolerant.

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

The BST pin supplies gate drive voltage to the internal high-side MOSFET via a bootstrap capacitor connected between BST and SW. A 100nF ceramic capacitor is recommended, placed as close as possible to the BST and SW pins. This capacitor charges during the low-side conduction phase (when SW ≈ GND) and provides ~4V to drive the MOSFET gate above VIN during high-side conduction, enabling efficient synchronous-like operation without a second switch.

Is thermal derating required when operating above 85°C ambient?

Yes. The MP2488DN-LF-Z is rated for operation from –40°C to +85°C ambient, but junction temperature must remain ≤125°C. Using the SOIC8E package's θJA = 50°C/W, power dissipation must be reduced linearly above +25°C ambient. At +85°C ambient, maximum allowable power is (125 − 85)/50 = 0.8W, limiting practical LED current to ~1.1A at 12V input unless additional heatsinking is applied to the exposed pad.

What failure protections are built into MP2488DN-LF-Z?

The MP2488DN-LF-Z integrates thermal shutdown (150°C trip, 130°C release), input UVLO (3.0V rising, 2.6V falling), cycle-by-cycle current limiting (3.2A), and bootstrap UVLO (2.2V). It also features internal soft-start to prevent startup current surges and COMP pin clamping to avoid control loop saturation. These protections operate autonomously without external components, ensuring robust fault recovery in unattended lighting systems.