Monolithic Power Systems Inc. MPQ2489DQ-LF-P

Overview

MPQ2489DQ-LF-P from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified step-down white LED driver IC with 6V–55V input range, integrated 60V/1.41A MOSFET, hysteretic control architecture, 202mV feedback reference voltage, and dual PWM/analog dimming support. It regulates LED current via high-side sensing for automotive interior lighting, emergency signage, and low-voltage halogen replacement.

For engineers reviewing the MPQ2489DQ-LF-P datasheet, MPQ2489DQ-LF-P pinout, MPQ2489DQ-LF-P application, or MPQ2489DQ-LF-P equivalent, key selection criteria include input voltage range compatibility, thermal performance in QFN6 package, dimming interface behavior (EN/DIM pin logic), and open/short LED protection implementation.

Technical Context

The MPQ2489DQ-LF-P uses a hysteretic control loop that eliminates need for external compensation while delivering fast transient response and stable regulation of LED current through a high-side sense resistor. Its internal 1.275V reference sets both enable threshold and current-sense comparator reference, enabling direct analog dimming via EN/DIM pin voltage modulation.

Thermal shutdown activates at 150°C junction temperature, and inherent open-LED and short-LED protection operate without auxiliary circuitry. The device supports soft-start via external capacitor on EN/DIM, with startup time programmable to 0.3–0.5ms using 4.7nF.

Key Specifications

Pinout & Package

MPQ2489DQ-LF-P is housed in a thermally enhanced QFN6 (3mm × 3mm, 0.75mm height) package with exposed thermal pad. Pin 2 and Pin 5 are internally connected GND terminals for optimal thermal and electrical grounding.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED current regulation applications.

Compared with LT3476EFE#PBF and TPS92630QPWPRQ1, MPQ2489DQ-LF-P uniquely combines AEC-Q100 qualification, integrated 60V MOSFET, and 1.41A output in a 3×3mm QFN-making it optimal for compact, high-reliability automotive LED modules where board space and thermal management are critical.

Availability

MPQ2489DQ-LF-P is available at Aetrix Electronics and suitable for automotive interior lighting, emergency signage, and low-voltage halogen replacement requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MPQ2489DQ-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 power ICs, with design centers in the US, China, and Taiwan.

The MPQ2489 belongs to MPS's automotive-grade LED driver product line, engineered specifically for robust, high-efficiency constant-current regulation in harsh environments such as vehicle cabins and industrial enclosures.

FAQ

What is the maximum recommended PWM dimming frequency for MPQ2489DQ-LF-P?

The datasheet specifies a recommended PWM dimming frequency range of 100Hz to 2kHz. Operation above 2kHz may cause inconsistent average current regulation due to finite EN/DIM pin response time and internal comparator propagation delay. For flicker-free operation in automotive applications, 1kHz is commonly used to balance resolution and timing margin.

Does MPQ2489DQ-LF-P require external compensation components?

No. The MPQ2489DQ-LF-P uses a hysteretic control architecture that inherently stabilizes the switching loop without requiring external RC compensation networks. This eliminates tuning effort and reduces bill-of-materials cost compared to voltage-mode or current-mode controllers.

How does the EN/DIM pin function in analog dimming mode?

In analog dimming mode, a DC voltage from 0.3V to 2.5V applied to EN/DIM linearly scales the internal current-sense reference from 25% to 200% of nominal LED current. At 0.3V, output current is ~25% of full scale; at 2.5V, it reaches 200%, enabling overdrive for pulse-brightening effects.

What is the purpose of the RS pin and how is LED current set?

The RS pin is the high-side current-sense input. LED current is set by a resistor (R_SET) placed between IN and RS: R_SET = 202mV / I_LED. For example, a 0.36Ω resistor sets 550mA. Accuracy depends on resistor tolerance and layout symmetry to minimize parasitic voltage drop.

Is the thermal pad on the QFN6 package electrically connected?

Yes. The exposed thermal pad on the MPQ2489DQ-LF-P QFN6 package is internally connected to GND. It must be soldered to a dedicated PCB thermal pad tied to multiple vias and internal ground planes to achieve specified θ_JA = 50°C/W and prevent thermal shutdown under full load.

Can MPQ2489DQ-LF-P drive LEDs with forward voltage higher than input voltage?

No. As a step-down (buck) converter, MPQ2489DQ-LF-P requires the total LED string forward voltage to be less than the input voltage minus diode drop and MOSFET saturation voltage. For example, with 36V input and 3×3.2V LEDs (9.6V), headroom is sufficient; it cannot boost or invert voltage.

What failure modes does the built-in open-LED protection detect?

Open-LED protection triggers when no current flows through the RS sense resistor for >100ms, causing the IC to disable the SW pin and enter latched-off state. It detects broken LED bonds, disconnected traces, or failed solder joints - but does not distinguish between open and high-resistance faults.