Monolithic Power Systems Inc. MP2489DN-LF-P

Overview

MP2489DN-LF-P from Monolithic Power Systems is a step-down white LED driver IC with 6V–60V input range, integrated 65V MOSFET, ≥1A output current capability, 202mV feedback reference voltage, and hysteretic control architecture-designed for automotive decorative lighting and emergency signage where wide-input, high-efficiency constant-current LED regulation is required.

For engineers reviewing the MP2489DN-LF-P datasheet, MP2489DN-LF-P pinout, MP2489DN-LF-P application, or MP2489DN-LF-P equivalent, this page delivers verified technical context, SOIC8E package mapping, PWM/analog dimming implementation details, thermal shutdown behavior, and real-world efficiency vs. input voltage performance data.

Technical Context

The MP2489DN-LF-P implements a hysteretic control loop that regulates LED current via high-side sensing across an external resistor, eliminating need for loop compensation while delivering sub-100ns response to load transients. Its internal 1.275V reference sets both EN/DIM pull-up and current-sense threshold scaling.

It supports dual dimming modes: analog dimming (0.3V–2.5V DC on EN/DIM linearly adjusts LED current from 25% to 200%), and PWM dimming (100Hz–2kHz square wave with 1000:1 resolution), with inherent open-LED and short-LED protection triggered by current-sense fault detection.

Key Specifications

Pinout & Package

MP2489DN-LF-P is housed in an SOIC8E (Small Outline Integrated Circuit, 8-pin, exposed pad) package with 1.27mm pitch and thermally enhanced backside paddle connected to GND. The exposed pad improves thermal resistance to 48°C/W (θJA) and 10°C/W (θJC), enabling ≥1.44A continuous output under proper PCB layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down white LED driver applications.

Compared with MPQ2489DN-AEC1, the MP2489DN-LF-P trades automotive qualification for lower unit cost and identical performance in industrial lighting; versus LT3476EFE#PBF, it delivers simpler single-string integration and 60V input tolerance at the expense of multi-channel flexibility.

Availability

MP2489DN-LF-P is available at Aetrix Electronics and suitable for automotive interior lighting, emergency exit signage, low-voltage halogen replacement, and architectural accent lighting requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MP2489DN-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 mixed-signal ICs for power management, motion control, and interface applications.

The MP2489 belongs to MPS's white LED driver product line, engineered specifically for wide-input, high-efficiency constant-current regulation in automotive, industrial, and architectural lighting systems where reliability and thermal resilience are critical.

FAQ

What is the maximum LED string voltage supported by MP2489DN-LF-P?

The MP2489DN-LF-P does not regulate output voltage directly-it regulates LED current via high-side sensing. The maximum LED string voltage is limited only by the 65V MOSFET breakdown rating minus input voltage headroom. With 60V input, up to ~55V LED forward voltage is feasible assuming sufficient inductor DCR margin and thermal derating.

Can MP2489DN-LF-P drive more than three white LEDs in series?

Yes-provided total LED forward voltage remains below VIN minus diode drop and MOSFET R_DS(on) × I_LED. At 60V input and 3.2V/V LED, up to 17–18 LEDs are theoretically possible; however, efficiency drops above ~12 LEDs due to increased conduction losses, and thermal limits in SOIC8E constrain practical use to ≤10 LEDs at full 1A.

How is analog dimming implemented on the EN/DIM pin?

Analog dimming applies a 0.3V–2.5V DC voltage to EN/DIM, which linearly scales the internal 202mV current-sense reference from 50mV to 505mV. This directly modulates average LED current from 25% to 200% of nominal setpoint-enabling silent, EMI-free dimming without PWM frequency artifacts.

Does MP2489DN-LF-P require external compensation components?

No-its hysteretic control architecture eliminates the need for external compensation networks. Stability is inherent due to fixed hysteresis band (±30mV around 202mV), enabling immediate transient response and eliminating phase-margin analysis or loop-tuning effort during design.

What is the recommended input capacitor value and type?

A 10µF–22µF X5R/X7R ceramic capacitor rated ≥63V is recommended, placed within 3mm of the IN and GND pins. Low-ESR construction minimizes input ripple and suppresses high-frequency switching noise; bulk electrolytic capacitance is unnecessary due to the device's low quiescent current and hysteretic regulation.

How does thermal shutdown behave during overload conditions?

When junction temperature reaches 150°C, the IC disables the internal MOSFET and holds EN/DIM low until die temperature falls below ~135°C hysteresis threshold. During shutdown, the device draws only 108µA, allowing safe cooldown without external intervention-critical for sealed emergency lighting enclosures.

Is the exposed pad on MP2489DN-LF-P electrically connected?

Yes-the exposed pad is internally tied to GND and must be soldered to a dedicated thermal pad on the PCB connected to a large GND plane. It is not optional: omitting this connection degrades θJA by >20°C/W and risks thermal shutdown at ≤0.8A load, violating SOIC8E thermal specifications.