Monolithic Power Systems Inc. MP2483DQ-LF-Z

Overview

MP2483DQ-LF-Z from Monolithic Power Systems is a 55V, 2.5A white LED driver IC supporting buck, inverting buck-boost, and step-up/down topologies with programmable switching frequency (default 1.35 MHz), 0.198 V feedback reference, and integrated 0.28 Ω MOSFET switch - used in LCD backlighting, automotive interior lighting, and portable multimedia devices.

For engineers reviewing the MP2483DQ-LF-Z datasheet, MP2483DQ-LF-Z pinout, MP2483DQ-LF-Z application, or MP2483DQ-LF-Z equivalent, key selection criteria include its dual dimming capability (DC/PWM on single EN/DIM pin), open-string and short-circuit protection, thermal shutdown, and compatibility with low-ESR ceramic output capacitors without minimum LED count requirement.

Technical Context

The MP2483DQ-LF-Z employs current-mode control with slope compensation for stable operation across wide duty cycles (up to 90%) and fast transient response. Its error amplifier integrates FB–VSS voltage error against a precise 0.198 V reference to regulate LED current via external sense resistor.

It implements multi-level fault handling: cycle-by-cycle overcurrent limiting (3.0 A peak), OVP-triggered shutdown (1.2 V threshold), foldback frequency reduction during output short (<0.4 V on OVP), and thermal shutdown at 150 °C - all operating within –40 °C to +125 °C junction range.

Key Specifications

Pinout & Package

MP2483DQ-LF-Z is housed in a thermally enhanced 10-pin 3 mm × 3 mm QFN package with exposed thermal pad connected to VSS. Pin layout supports compact PCB design with dedicated INGND reference for noise-immune dimming control and BST bootstrap node for high-side gate drive.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2483DQ-LF-Z, the MPQ2483DQ-LF-Z adds automotive qualification at minor cost premium but retains identical pinout and electrical behavior, while the LT3466-1EDD#TRPBF sacrifices topology flexibility and protection intelligence for lower BOM count in static designs.

Availability

MP2483DQ-LF-Z is available at Aetrix Electronics and suitable for LCD backlight panels, automotive interior lighting, and portable multimedia players requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.

Supply support for MP2483DQ-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, headquartered in Kirkland, Washington, with global design and support operations.

The MP2483 belongs to MPS's white LED driver product line, engineered specifically for high-efficiency, flexible topology LED illumination in space-constrained and thermally demanding environments - emphasizing integration, protection, and dimming versatility.

FAQ

What is the function of the INGND pin on MP2483DQ-LF-Z?

The INGND pin serves as an isolated reference ground for the EN/DIM control signal, decoupling dimming commands from high-noise power ground paths. It enables clean analog dimming and reliable PWM edge detection by preventing switching transients on VSS from distorting the dimming voltage threshold - critical for flicker-free operation in sensitive displays.

Can MP2483DQ-LF-Z drive LEDs in true boost configuration?

No - MP2483DQ-LF-Z does not support standard non-inverting boost topology. It operates in buck, inverting buck-boost (step-up/down), or inverting boost modes only. True boost requires the LED anode connected to input and cathode to SW, which is unsupported; its architecture relies on VSS-referenced FB and OVP sensing, limiting it to configurations where LED current flows toward VSS.

How is switching frequency set when RSET is left unconnected?

When the RSET pin is left open (no resistor to VSS), MP2483DQ-LF-Z defaults to 1.35 MHz ±15% switching frequency, as specified in the Electrical Characteristics table. This factory-trimmed oscillator eliminates external components for designs prioritizing simplicity and board area savings, though RSET remains available for EMI tuning or efficiency optimization.

What happens during output short-circuit condition?

During output short to VSS, the OVP pin voltage drops below 0.4 V and FB senses near-zero voltage (<0.1 V), triggering foldback mode: switching frequency reduces to 250 kHz to limit power dissipation. The IC remains operational but delivers minimal current until fault clears - distinct from full shutdown, enabling automatic recovery without reset.

Is the exposed thermal pad on MP2483DQ-LF-Z electrically connected?

Yes - the exposed pad is internally bonded to VSS and must be soldered to a PCB copper pour tied to the main VSS net. This connection provides primary thermal conduction path (θ_JC = 12 °C/W) and ensures safe operation at 2.5 A continuous output; omitting this connection risks thermal shutdown or premature failure.

Does MP2483DQ-LF-Z require an external Schottky diode in all configurations?

Yes - an external Schottky diode is mandatory in all topologies to provide freewheeling path for inductor current. In buck mode, it connects cathode to SW and anode to VSS; in buck-boost, cathode to SW and anode to LED+ (or VOUT). MPS recommends low-V_F, low-Q_RR diodes such as MBR0540 or SS14 for optimal efficiency and EMI performance.

What is the minimum recommended output capacitor value?

The minimum recommended output capacitor is 2.2 µF X5R/X7R ceramic, placed close to the FB and VSS pins. This value ensures loop stability and limits output ripple to <100 mV peak-to-peak under full load; smaller values risk oscillation or poor dimming linearity, especially with PWM frequencies above 1 kHz.