Monolithic Power Systems Inc. MP4689AGN-P

Overview

MP4689AGN-P from Monolithic Power Systems is a 100V-input, 1A constant-current LED driver IC with integrated high-side MOSFET (3.5A current limit), hysteresis current-mode control, ±3% LED current accuracy, and 20kHz PWM dimming capability. It operates in step-down topology for automotive headlamps, industrial high-bay lighting, and battery-powered emergency lighting systems.

For engineers reviewing the MP4689AGN-P datasheet, MP4689AGN-P pinout, MP4689AGN-P application, or MP4689AGN-P equivalent, key selection criteria include its 4.5–100V input range, 200mV FB reference voltage, SOIC-8 EP thermal performance (θJA = 50°C/W), 170µA quiescent current, and dedicated DIM/EN logic-level control inputs.

Technical Context

The MP4689AGN-P implements hysteresis current-mode control with adaptive 185mV/215mV FB thresholds to achieve ±3% LED current regulation without external compensation. Its internal high-side MOSFET (RDS(ON) = 500mΩ) and bootstrap-regulated floating gate driver enable operation up to 1MHz switching frequency.

LED current is set via an external sense resistor referenced to a precise 200mV average FB voltage. Protection includes thermal shutdown (150°C trip), short-circuit detection (<10µs response), and UVLO (4.0V rising / 3.65V falling threshold) - all implemented in a single-die solution.

Key Specifications

Pinout & Package

MP4689AGN-P is housed in a SOIC-8 package with exposed thermal pad (EP), optimized for high-power LED driver thermal management. The exposed pad must be soldered to a PCB ground plane using ≥9 thermal vias (15mil barrel, 40mil pitch) for effective heat conduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT3474EFE#PBF and TPS92692QPWPRQ1, the MP4689AGN-P uniquely combines 100V input tolerance, integrated 3.5A MOSFET, hysteretic control for zero-compensation design, and SOIC-8 EP thermal performance - making it optimal for cost-sensitive, high-reliability industrial and commercial LED drivers where input voltage variation exceeds 65V.

Availability

MP4689AGN-P is available at Aetrix Electronics and suitable for automotive headlamp systems, industrial high-bay lighting fixtures, and battery-powered emergency lighting requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for MP4689AGN-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 over two decades of leadership in DC/DC conversion, LED drivers, and motor control solutions.

The MP4689A belongs to MPS's high-voltage LED driver product line, engineered specifically for ruggedized constant-current regulation in automotive, industrial, and outdoor lighting where wide input range, thermal resilience, and minimal external components are critical.

FAQ

What is the maximum continuous LED current the MP4689AGN-P can deliver?

The MP4689AGN-P delivers up to 1A of continuous constant current to LED strings. This is set by the external sense resistor (R_FB) and the 200mV average FB reference voltage. Peak switch current is limited to 3.5A internally, ensuring safe operation even under transient overloads or startup surges.

Can the MP4689AGN-P operate without an output capacitor?

Yes - the MP4689AGN-P is designed to operate without an output capacitor. Its hysteresis control inherently limits LED current ripple to ≤15% of DC value. An optional output capacitor may be added to further reduce ripple, but it is not required for stability or basic functionality.

How does the DIM pin interface with standard microcontroller PWM outputs?

The DIM pin accepts standard 3.3V or 5V logic-level PWM signals. Its 0.8–1.5V threshold range and 50ns propagation delay ensure compatibility with most MCUs. No level-shifting is needed; direct connection to GPIO pins with 10kΩ pull-down (if inactive-low default required) suffices.

What thermal design practices are mandatory for SOIC-8 EP mounting?

The exposed pad must be soldered to a solid internal or external GND plane using ≥9 thermal vias (15mil barrel, 40mil pitch). Avoid splitting the pad or routing traces underneath. PCB layout must place input capacitor, catch diode, and IC VIN/SW/GND nodes within 5mm to minimize loop inductance and SW node ringing.

Does the MP4689AGN-P support analog dimming in addition to PWM?

No - the MP4689AGN-P supports only PWM dimming via the dedicated DIM pin. Analog dimming (current reduction via FB voltage adjustment) is not supported; the FB pin is strictly for current-sense feedback with fixed 200mV regulation target.

What failure protections are built into the MP4689AGN-P?

It includes thermal shutdown (150°C trip), LED short-circuit protection (10µs detection, auto-retry), input UVLO (4.0V rising / 3.65V falling), and internal MOSFET overcurrent limiting (3.5A peak). All protections are fully integrated - no external components required.

Is the MP4689AGN-P pin-compatible with earlier MP4689A variants?

Yes - MP4689AGN-P is a Pb-free, halogen-free, RoHS-compliant variant of the MP4689AGN, sharing identical pinout, electrical characteristics, and thermal profile. The "-P" suffix denotes green packaging; no design changes or layout modifications are required for migration.