Monolithic Power Systems Inc. MP24892DJ-LF-P

Overview

MP24892DJ-LF-P from Monolithic Power Systems is a high-efficiency, hysteretic-controlled step-down white LED driver IC designed for constant-current LED biasing in wide-input industrial and automotive lighting systems. It operates from 6V to 45V input, delivers up to 1A output current with ±5% LED current accuracy, features 202mV typical feedback reference voltage, and integrates thermal shutdown and open/short LED protection. It is used in emergency signage backlighting where stable current regulation across varying battery voltages is critical.

For engineers reviewing the MP24892DJ-LF-P datasheet, MP24892DJ-LF-P pinout, MP24892DJ-LF-P application, or MP24892DJ-LF-P equivalent, key selection considerations include its 1000:1 PWM dimming resolution, TSOT23-5 package thermal performance (θJA = 100°C/W), dual analog/PWM dimming interface on EN/DIM, and inherent open-LED fault detection without external circuitry.

Technical Context

The MP24892DJ-LF-P implements a fixed-frequency hysteretic control architecture-no loop compensation required-that regulates LED current by comparing the voltage across an external high-side sense resistor against a 202mV ±30mV internal reference. Its 1.275V internal reference sets both enable threshold and current scaling, enabling linear analog dimming from 25% to 200% I_OUT via 0.3V–2.5V DC on EN/DIM.

It integrates a 0.5Ω R_DS(ON) internal MOSFET switch, supports 0.1–2kHz PWM dimming with NPN-level shifting, and provides inherent protection against open-circuit and short-circuit LED faults through sensing and shutdown logic-without requiring additional comparators or timers.

Key Specifications

Pinout & Package

MP24892DJ-LF-P is housed in a thermally enhanced TSOT23-5 package (2.9mm × 1.6mm × 0.9mm), optimized for compact LED driver layouts with exposed pad thermal path (θJC = 55°C/W). The 5-pin configuration supports minimal external components and high-density PCB placement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT3474EDD#TRPBF and TPS61165DRVR, MP24892DJ-LF-P uniquely combines wide 6–45V buck operation, ultra-low 202mV sense voltage, and single-pin dual-dimming-making it optimal for cost-sensitive, thermally constrained, and input-voltage-variable LED lighting where simplicity and efficiency are primary.

Availability

MP24892DJ-LF-P is available at Aetrix Electronics and suitable for emergency signage, automotive interior lighting, and low-voltage halogen replacement requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP24892DJ-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, and global manufacturing partnerships.

The MP24892 belongs to MPS's high-voltage LED driver product line, engineered specifically for robust, efficient, and compact constant-current driving of white LEDs in harsh-input environments such as transportation and industrial lighting.

FAQ

What is the minimum recommended input voltage for reliable startup?

The MP24892DJ-LF-P guarantees operation down to 6V, but startup is ensured at VIN ≥ 6.2V due to internal bandgap and reference stabilization requirements. Below this, EN/DIM may not pull up reliably, causing intermittent enable behavior. For cold-cranking automotive use, verify minimum battery voltage under load meets this threshold.

Can the EN/DIM pin be left floating for default operation?

No-leaving EN/DIM open results in undefined behavior due to internal 2µA pull-up current and noise susceptibility. The datasheet specifies that the pin must be either pulled to GND (disable), biased with 0.3–2.5V (analog dimming), or driven with a clean PWM signal. A 47kΩ pull-up to VIN is acceptable for full-brightness enable-only use.

How does the 202mV feedback voltage affect sense resistor selection?

R_SENSE is calculated as 0.202V ÷ I_LED. For a 550mA target, R_SENSE = 0.367Ω (standard 0.36Ω). This low value reduces power loss to 62mW versus 550mW at 1V, allowing use of smaller, non-inductive 0805 resistors without derating or forced airflow.

Does the MP24892DJ-LF-P support synchronous rectification?

No-it uses an internal N-channel MOSFET switch and requires an external Schottky diode for freewheeling. Synchronous operation is not supported; the SW pin is not designed to drive an external low-side FET gate. Diode selection must prioritize low V_F and fast recovery to maintain >95% efficiency.

What failure modes trigger automatic shutdown?

Thermal shutdown activates at 150°C junction temperature. Open-LED protection triggers when RS pin voltage exceeds VIN (indicating open sense path), and short-LED protection engages when RS voltage falls below ~50mV (indicating shunted or failed LED string). All cause immediate latch-off until power cycle or EN/DIM reset.

Is the TSOT23-5 package lead-free and RoHS compliant?

Yes-MP24892DJ-LF-P is fully lead-free and RoHS compliant per EU Directive 2011/65/EU. The "-LF" suffix explicitly denotes lead-free finish, and MPS confirms green status on its Quality Assurance page with full material declarations available upon request.

Can analog and PWM dimming be used simultaneously?

No-the EN/DIM pin supports only one dimming mode at a time. Applying both a DC bias and PWM signal causes unpredictable current regulation due to competing reference modulation. Designers must select either analog (DC voltage) or PWM (square wave) based on system controller capability and flicker requirements.