Monolithic Power Systems Inc. MP24183DQ-LF-P

Overview

MP24183DQ-LF-P from Monolithic Power Systems is a 55V, 1A white LED driver IC supporting buck, boost, and buck-boost topologies with programmable switching frequency (250 kHz to 1.65 MHz), 0.198 V feedback reference, and integrated 0.28 Ω MOSFET. It delivers precise constant-current regulation for LED strings in automotive interior lighting and portable display backlighting.

For engineers reviewing the MP24183DQ-LF-P datasheet, MP24183DQ-LF-P pinout, MP24183DQ-LF-P application, or MP24183DQ-LF-P equivalent, key selection criteria include its dual dimming capability (analog/PWM on EN/DIM), open-string and short-circuit protection, thermal shutdown, and compatibility with low-ESR ceramic output capacitors.

Technical Context

The MP24183DQ-LF-P implements current-mode control with slope compensation for stable loop response across wide duty cycles. Its architecture supports three operating modes-step-down (buck), step-up (boost), and inverting buck-boost-enabled by external component configuration and internal switch topology.

It integrates cycle-by-cycle overcurrent limiting, input overvoltage protection (OVP pin threshold 1.2 V), and fold-back frequency reduction during output short circuit (triggered when OVP < 0.4 V and FB < 0.1 V). Dimming is implemented via a single EN/DIM pin accepting 0.7–1.4 V analog control or 100 Hz–2 kHz PWM signals ≥1.4 V amplitude.

Key Specifications

Pinout & Package

The MP24183DQ-LF-P is housed in a thermally enhanced 10-pin 3 mm × 3 mm QFN package with exposed thermal pad connected to VSS. The package supports high-power dissipation (θ_JA = 50 °C/W) and requires solder reflow per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP24183DQ-LF-P, MP2483DJ-LF-Z offers identical functionality with enhanced thermal and EMI robustness, while LM3409HVMM/NOPB trades integration for flexibility in high-current or custom-switching designs-but requires additional components and lacks built-in fault protections.

Availability

MP24183DQ-LF-P is available at Aetrix Electronics and suitable for automotive interior lighting, LCD backlight panels, handheld computers, and portable GPS devices requiring stable component supply during legacy design support and end-of-life transition phases.

Supply support for MP24183DQ-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, LED lighting, and motor control applications.

The MP24183 belongs to MPS's white LED driver product line, designed specifically for high-voltage, high-current constant-current regulation in automotive, industrial, and portable display systems with stringent reliability and protection requirements.

FAQ

What is the recommended RSET resistor value to achieve 1 MHz switching frequency?

The MP24183DQ-LF-P datasheet specifies that a 100 kΩ resistor from RSET to VSS sets the switching frequency to approximately 1 MHz. This value is derived from the RSET–frequency curve in the application section; deviation beyond ±5% may shift frequency outside target range due to process variation.

Can the MP24183DQ-LF-P drive LEDs in series-only configuration, or does it require parallel strings?

The MP24183DQ-LF-P regulates current through a single external sense resistor, making it compatible with both series and parallel LED configurations-as long as total forward voltage stays within the selected topology's output capability (e.g., ≤55 V in buck mode). Series strings are preferred for current uniformity.

How does the open-string protection mechanism respond during startup?

During startup, if no LED string is connected, FB remains near 0 V. The controller increases duty cycle until either the OVP pin reaches 1.2 V (causing shutdown) or VDD–VSS hits 55 V. Recovery occurs automatically once OVP voltage drops below hysteresis threshold (1.14 V) after fault removal.

Is the INGND pin required to be tied directly to system ground in all configurations?

No-INGND serves as the reference for EN/DIM and must be connected to the same potential as the dimming signal source. In buck-boost applications where EN/DIM is referenced to a floating node, INGND is isolated from VSS and tied to that local reference to prevent ground-loop interference.

What is the maximum allowable inductor DCR for stable 1 A operation in buck mode?

For stable 1 A operation, the inductor DCR should be ≤200 mΩ per the datasheet recommendation. Higher DCR increases conduction loss and thermal stress on the IC, potentially triggering thermal shutdown before reaching rated current-especially at high ambient temperatures.

Does the MP24183DQ-LF-P support synchronous rectification?

No-the MP24183DQ-LF-P uses an internal N-channel MOSFET switch and requires an external Schottky diode (e.g., B360A) for flyback path conduction. It does not integrate or support synchronous rectifier control signals, limiting peak efficiency to ~92% in typical buck implementations.

What happens to dimming linearity when using PWM frequencies above 2 kHz?

PWM frequencies above 2 kHz degrade dimming linearity due to insufficient on-time resolution at the internal comparator level; the datasheet explicitly recommends 100 Hz–2 kHz for optimal 0–100% current control. Frequencies >5 kHz may cause visible flicker or inconsistent brightness steps.