Monolithic Power Systems Inc. MP4603ES-LF-P

Overview

MP4603ES-LF-P from Monolithic Power Systems is a current-mode buck-boost white LED driver IC designed for large LCD TV backlight systems (60-inch and larger), supporting LED string voltages up to 350V with dual-input architecture (12V low-side + high-voltage bias). It integrates a 0.5Ω internal MOSFET, delivers regulated output voltage from VINH to VINH+68V, achieves ≥99.5% efficiency, and supports >1:1000 dimming ratio via combined PWM and analog control.

For engineers reviewing the MP4603ES-LF-P datasheet, MP4603ES-LF-P pinout, MP4603ES-LF-P application, or MP4603ES-LF-P equivalent, key selection criteria include its novel power-leverage-control topology, SOIC16 package thermal performance (θJA = 80°C/W), ±5% 200mV FB reference accuracy, 10μA shutdown current, and fault signaling via open-drain FAULT pin tied to INGND.

Technical Context

The MP4603ES-LF-P implements peak-current-mode buck-boost regulation with programmable slope compensation (0.12–0.235 V/μs) to maintain stability at duty cycles >50%. Its dual-input architecture separates low-voltage control (VINL = 5–80V) from high-voltage bias (VINH), enabling efficient high-string-voltage drive without high-side gate drivers.

It features integrated protection logic: LED open detection via OVP latch-off at 1.2V, LED short detection with dual-threshold response (600mV immediate latch-off; 300mV for 450μs delay), cycle-by-cycle current limiting (2.5A), and thermal shutdown at 150°C with 20°C hysteresis - all signaled through the FAULT pin.

Key Specifications

Pinout & Package

MP4603ES-LF-P is housed in a 16-pin SOIC package (body width 3.90 mm, lead pitch 1.27 mm) with exposed pad not present; thermal resistance θJA = 80°C/W on JEDEC-standard 4-layer PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP4602ES-LF-P, the MP4603ES-LF-P enables larger-panel scalability via 350V string support and higher efficiency; versus LM3409HVMM/NOPB, it reduces component count and layout complexity by integrating the power switch and dual-input bias architecture.

Availability

MP4603ES-LF-P is available at Aetrix Electronics and suitable for large-screen LCD TV backlighting, commercial digital signage, high-power LED street lighting, and industrial control panel displays requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP4603ES-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 manufacturing partners across Asia.

The MP4603 belongs to MPS's high-voltage LED driver product line, engineered specifically for energy-efficient, high-reliability backlight solutions in premium consumer displays and industrial lighting where compact size, thermal resilience, and deep dimming are critical.

FAQ

What is the maximum LED string voltage supported by MP4603ES-LF-P?

The MP4603ES-LF-P supports LED string voltages up to 350V when configured with appropriate VINH bias and output regulation range (VINH to VINH+68V). This is validated in the datasheet's typical application circuits and design examples for 60-inch+ LCD TVs, where VINH is set to ~145V and output reaches ~180V under load.

How does the power-leverage-control technology improve efficiency?

Power-leverage-control reduces voltage stress on the internal MOSFET by regulating only a small portion of the total LED string voltage using the low-voltage input (e.g., 12V), while leveraging a fixed high-voltage bias (VINH) for the majority. This enables higher switching frequencies, smaller passive components, and reduced conduction losses - resulting in ≥99.5% peak efficiency.

Can MP4603ES-LF-P operate without an external high-voltage bias source?

No. The MP4603ES-LF-P requires two independent supplies: a low-voltage input (VIN, 5–80V) for control circuitry and gate drive, and a high-voltage bias (VINH) applied to the LED anode side. Without VINH, the device cannot generate the required output voltage swing to drive high-string-voltage LEDs - the architecture fundamentally depends on this dual-rail configuration.

What happens during LED open-circuit fault condition?

During LED open, FB voltage drops near 0V, causing the controller to increase duty cycle until OVP pin voltage reaches 1.2V. At that point, the internal switch latches off, DGD goes low, and FAULT pin pulls to INGND. Recovery requires cycling the EN pin - no automatic restart - ensuring safe fault containment before system reset.

Is the SOIC16 package thermally adequate for 1.6W dissipation?

Yes. The SOIC16 package has a specified continuous power dissipation of 1.6W at TA = +25°C (θJA = 80°C/W). Under real-world conditions with proper PCB copper area and airflow, it sustains full-load operation within its 150°C junction limit. Thermal shutdown activates at 150°C with 20°C hysteresis, providing robust protection during transient overloads.

How is analog dimming implemented on the ADIM pin?

Analog dimming is implemented by applying 0–1.2V to the ADIM pin, which linearly scales the FB reference voltage from 0mV to 200mV - directly modulating LED current from 0% to 100%. Voltages above 1.2V or an open ADIM pin default to full-scale current. This analog path operates independently of PWM, enabling hybrid dimming with no timing interdependence.

Does MP4603ES-LF-P support spread-spectrum frequency modulation?

No. The MP4603ES-LF-P supports fixed-frequency or synchronized operation via the SYN pin, but does not include built-in spread-spectrum modulation. EMI reduction is achieved instead through programmable switching frequency (180–390kHz), tight layout guidelines, and the ability to phase-align multiple channels to cancel magnetic fields.