Monolithic Power Systems Inc. MPQ2483DQ-LF-Z

Overview

MPQ2483DQ-LF-Z from Monolithic Power Systems is a 55V, 2.5A peak-current industrial/automotive-grade LED driver IC supporting buck and inverting buck-boost topologies, featuring programmable switching frequency (250 kHz to 1.35 MHz), 0.198 V feedback reference, and integrated 0.28 Ω MOSFET - deployed in automotive headlamp modules and LCD backlight systems requiring AEC-Q100 compliance.

For engineers reviewing the MPQ2483DQ-LF-Z datasheet, MPQ2483DQ-LF-Z pinout, MPQ2483DQ-LF-Z application, or MPQ2483DQ-LF-Z equivalent, key selection criteria include input voltage range (4.5–55 V), dual dimming capability (DC/PWM on EN/DIM), open-string and short-circuit protection, thermal shutdown, and QFN-10 (3 mm × 3 mm) package compatibility with high-power density PCB layouts.

Technical Context

The MPQ2483DQ-LF-Z implements current-mode control with slope compensation for stable operation across wide duty cycles and load transients. Its error amplifier integrates FB-to-reference error and drives the PWM comparator, while cycle-by-cycle current limiting ensures precise 2.5 A peak switch current regulation independent of input voltage.

It supports three operating modes via external component configuration: step-down (buck), inverting step-up/down (buck-boost), and non-inverting boost. The RSET pin sets oscillator frequency using an external resistor, and the OVP pin enables programmable overvoltage shutdown at 1.2 V threshold with 60 mV hysteresis.

Key Specifications

Pinout & Package

MPQ2483DQ-LF-Z is housed in a thermally enhanced 10-pin QFN package (3 mm × 3 mm, 0.75 mm height) with exposed thermal pad connected to VSS. Pin 1 is marked by a dot; the exposed pad must be soldered to a dedicated VSS copper pour for thermal performance and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPQ2483DQ-LF-Z, MPQ2489DQ-LF-Z offers higher current headroom but identical feature set and footprint, while LM3409QMYX/NOPB lacks integrated fault protections and automotive qualification - making MPQ2483DQ-LF-Z optimal for safety-critical, compact, and thermally constrained designs.

Availability

MPQ2483DQ-LF-Z is available at Aetrix Electronics and suitable for automotive lighting, LCD backlighting, and industrial status indication requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.

Supply support for MPQ2483DQ-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 design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MPQ2483 belongs to MPS's automotive-grade LED driver product line, engineered specifically for robust, high-efficiency constant-current regulation in harsh environments - targeting headlamps, interior lighting, and display backlights where reliability and thermal resilience are critical.

FAQ

What is the maximum recommended LED string voltage for MPQ2483DQ-LF-Z in buck-boost mode?

In inverting buck-boost configuration, the maximum output voltage is limited by the 55 V absolute maximum VDD–VSS rating and the 1.2 V OVP threshold. With proper OVP divider design, sustained output voltages up to 50 V are achievable - verified in Figure 5 of the datasheet with seven 3 W LEDs (≈42 V total forward drop) at 0.7 A.

Can MPQ2483DQ-LF-Z operate without the RSET resistor?

Yes - leaving RSET open configures the default switching frequency at 1.35 MHz (typical), as specified in the Electrical Characteristics table. This mode is production-tested and supported; however, adding a 200 kΩ resistor lowers frequency to 250 kHz for reduced EMI in noise-sensitive applications.

How does the INGND pin improve dimming accuracy in automotive systems?

INGND provides a dedicated, low-noise reference for the EN/DIM pin, isolating dimming control signals from high-current VSS return paths. This prevents coupling of switching noise into analog dimming - critical for achieving <±2% LED current linearity across 0–100% dimming range in 12 V vehicle electrical systems.

Is the exposed thermal pad on the QFN-10 package electrically connected?

Yes - the exposed pad is internally bonded to VSS and must be soldered to a solid VSS copper pour. Thermal resistance drops from θ_JA = 50°C/W to ≤35°C/W when using ≥4 thermal vias (0.3 mm diameter) to inner-layer ground planes, directly impacting maximum continuous current capability.

Does MPQ2483DQ-LF-Z support daisy-chained PWM dimming across multiple ICs?

No - each MPQ2483DQ-LF-Z requires its own PWM signal on the EN/DIM pin. Synchronization across multiple devices is not supported; however, identical PWM waveforms applied in parallel achieve consistent dimming behavior, as confirmed in Typical Performance Characteristic "DIMMING DUTY vs LED CURRENT" on page 6.

What failure modes trigger foldback frequency operation?

Foldback occurs exclusively during output short-circuit conditions: when OVP pin voltage falls below 0.4 V *and* FB pin voltage drops below 0.1 V simultaneously - indicating zero LED current flow and direct short to INGND. Frequency reduces to 250 kHz to limit power dissipation and thermal stress.

How is open-LED protection implemented without a dedicated sense line?

Open-LED detection uses the OVP pin: with no LED current, FB voltage collapses, causing the controller to increase duty cycle until OVP voltage (set by external resistor divider) reaches 1.2 V. At that point, the switch disables and recovers only after OVP voltage falls by 60 mV hysteresis - eliminating need for auxiliary sensing circuitry.