Monolithic Power Systems Inc. MP24893DJ-LF-P

Overview

MP24893DJ-LF-P from Monolithic Power Systems is a hysteretic-controlled step-down white LED driver IC with 6V–36V input range, internal 36V/1A MOSFET, 200mV average feedback voltage, and dual PWM/analog dimming via EN/DIM pin-designed for automotive interior lighting, emergency signage, and low-voltage halogen replacement systems.

For engineers reviewing the MP24893DJ-LF-P datasheet, MP24893DJ-LF-P pinout, MP24893DJ-LF-P application, or MP24893DJ-LF-P equivalent, key selection criteria include its high-side current-sense architecture, 1000:1 PWM dimming resolution, thermal shutdown protection, UVLO threshold of 5.9V (rising), and TSOT23-5 package compatibility with space-constrained LED modules.

Technical Context

The MP24893 operates in continuous conduction mode using hysteretic control-eliminating loop compensation while delivering fast transient response and stable LED current regulation via external high-side sense resistor. Its 202mV ±30mV feedback reference (measured as VIN–VRS) directly sets LED current with minimal power loss.

Dimming is implemented through a single EN/DIM pin supporting both analog (0.3V–2.5V DC → 25%–200% current range) and PWM (100Hz–2kHz) modes; internal 1.275V reference and 45kΩ pull-up enable soft-start when capacitor-coupled, and under-voltage lockout triggers at 5.3V (rising) with 700mV hysteresis.

Key Specifications

Pinout & Package

MP24893DJ-LF-P is packaged in TSOT23-5-a 2.9mm × 1.6mm surface-mount package with exposed pad for thermal enhancement. Pin 1 is SW (internal MOSFET drain), Pin 2 is GND, Pin 3 is EN/DIM, Pin 4 is RS (current-sense input), and Pin 5 is IN (input supply). No NC pins; all five terminals are functional and validated per MPS datasheet Rev. 1.02.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP24895DJ-LF-Z, the MP24893DJ-LF-P offers identical pinout and basic functionality but lacks updated thermal specs and lower shutdown current; versus LT3476, it trades channel flexibility for integration, size, and cost savings in single-string applications.

Availability

MP24893DJ-LF-P is available at Aetrix Electronics and suitable for automotive interior lighting, emergency exit signage, and low-voltage halogen replacement requiring stable component supply and long-term obsolescence management.

Supply support for MP24893DJ-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 MP24893 belongs to MPS's white LED driver product line-engineered specifically for cost-sensitive, thermally constrained, single-string LED lighting in automotive, industrial, and architectural applications.

FAQ

What is the recommended current-sense resistor value for 1A LED output?

The MP24893 sets LED current using R_SENSE = 202mV / I_LED. For 1A output, R_SENSE = 0.202Ω. A standard 0.2Ω, 1% tolerance, 1W metal-strip resistor is recommended to ensure accuracy and thermal stability under continuous operation.

Can MP24893DJ-LF-P drive more than three white LEDs in series?

Yes-maximum LED string voltage depends on input voltage minus dropout. With 36V input and typical 0.2V sense loss + 0.4V diode drop, up to 10× white LEDs (3.2V each) can be driven at reduced current. However, efficiency declines above 80% duty cycle; verify thermal margin with θJA = 110°C/W.

Is the EN/DIM pin compatible with microcontroller GPIO without level-shifting?

Yes-the EN/DIM pin accepts 0.3V–2.5V for analog dimming and logic-high ≥1.5V for PWM dimming. Standard 3.3V or 5V MCU GPIO can drive it directly in open-drain PWM mode; for analog control, use a simple resistor divider if MCU DAC output exceeds 2.5V.

Why does the datasheet state "NOT RECOMMENDED FOR NEW DESIGNS"?

MPS issued this notice because MP24895-its pin-compatible successor-offers improved specifications: lower shutdown current (60µA vs. 120µA), better thermal resistance (90°C/W vs. 110°C/W), and extended analog dimming range (0.1V–2.5V). MP24893 remains fully qualified and supported for legacy production.

Does MP24893DJ-LF-P require an output capacitor?

No-output capacitance is optional. The datasheet states it is unnecessary for most applications. Only add a 2.2µF ceramic capacitor across the LED string if peak-to-peak current ripple must be held below 30% of average current, such as in high-precision color-mixing systems.

How is thermal performance affected by PCB copper area in TSOT23-5?

Thermal resistance θJA = 110°C/W assumes JEDEC-standard 4-layer board with 1in² of 2oz copper connected to the exposed pad. Reducing copper area to 0.25in² increases θJA to ~150°C/W-limiting max continuous current to ~700mA at TA = 85°C. Always follow MPS land pattern guidelines.

What failure modes does the internal thermal shutdown protect against?

The thermal shutdown circuit disables the internal MOSFET when junction temperature reaches 150°C, preventing permanent silicon damage due to sustained overload, inadequate heatsinking, or ambient temperature exceeding 125°C. Recovery occurs automatically once TJ falls below 135°C hysteresis threshold.