Monolithic Power Systems Inc. MP3202DG-LF-P

Overview

MP3202DG-LF-P from Monolithic Power Systems is a fixed-frequency, current-mode boost LED driver IC designed to drive up to 39 white LEDs (13 strings × 3) from a 2.5V–6V input rail. It integrates a 1.3A MOSFET switch, regulates LED current via a 104mV feedback voltage, and features open-load shutdown triggered at 28V on the OV pin. Used in compact backlighting systems requiring high efficiency (up to 92%) and PWM dimming support.

For engineers reviewing the MP3202DG-LF-P datasheet, MP3202DG-LF-P pinout, MP3202DG-LF-P application, or MP3202DG-LF-P equivalent, key selection criteria include its 1.0–1.5MHz switching frequency, internal current limit (1.33A), thermal shutdown (160°C), soft-start timing (120µs), and dual-package availability (QFN8-2×2mm or TSOT23-6).

Technical Context

The MP3202DG-LF-P implements a constant-frequency peak-current-mode boost architecture with a 1.3MHz oscillator and slope compensation to prevent subharmonic oscillation above 50% duty cycle. Its error amplifier compares FB voltage against a 104mV reference to control PWM comparator threshold.

It supports analog dimming via DC injection into FB and digital dimming via EN-pin PWM (≤1kHz recommended) or filtered PWM (for higher frequencies). Open-circuit protection is implemented by monitoring output voltage at the OV pin, shutting down the converter if >28V is detected.

Key Specifications

Pinout & Package

MP3202DG-LF-P is housed in an RoHS-compliant 8-pin QFN package (2mm × 2mm, 0.4mm pitch) with exposed thermal pad for enhanced heat dissipation (θ_JA = 80°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with RT9397BZSP and AP3012KTR-G1, MP3202DG-LF-P provides integrated OV fault detection and thermal shutdown in a 2×2mm QFN, delivering higher functional safety and reduced external component count for portable backlighting.

Availability

MP3202DG-LF-P is available at Aetrix Electronics and suitable for cell phone backlighting, digital camera LCDs, handheld PDA displays, and small industrial HMI panels requiring stable component supply and long-term production continuity.

Supply support for MP3202DG-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.

The MP3202 belongs to MPS's white LED driver product line, engineered specifically for compact, high-efficiency backlighting in battery-powered portable devices with stringent thermal and reliability requirements.

FAQ

What is the maximum number of white LEDs the MP3202DG-LF-P can drive?

The MP3202DG-LF-P can drive up to 39 white LEDs arranged in 13 parallel strings of 3 series-connected LEDs each, assuming a typical forward voltage of 3.2V per LED and 5V input. Total output voltage reaches up to 25V, limited by the 28V OV threshold.

Does MP3202DG-LF-P support analog dimming, and how is it implemented?

Yes - analog dimming is implemented by injecting a DC voltage (0–2V) into the FB pin through a resistor network. This diverts current away from the LED string, reducing regulated current proportionally while maintaining 104mV at FB. No external op-amp or DAC is required.

What is the purpose of the NC pin (Pin 7) in the QFN8 package?

Pin 7 is designated "No Connect" in the MP3202DG-LF-P QFN8 package and must remain unconnected on the PCB. It has no internal connection and serves only as a mechanical placeholder; routing or soldering to this pin may cause unintended electrical coupling or thermal imbalance.

Can MP3202DG-LF-P operate reliably at 2.5V input, and what is the minimum startup voltage?

Yes - the MP3202DG-LF-P operates down to 2.5V input and starts up reliably at VIN ≥ 2.45V (UVLO rising threshold). At 2.5V, it delivers reduced LED current due to lower duty cycle headroom, but maintains regulation and protection functions across the full –40°C to +85°C range.

How does the soft-start function behave during repeated enable/disable cycles?

The soft-start timer resets on every EN pin high-to-low transition. Each activation ramps the current limit in three 40µs steps (0 → 0.33A → 0.66A → 1.33A), ensuring controlled inrush regardless of prior state - critical for PWM dimming with frequent toggling.

Is the exposed thermal pad on the QFN8 package electrically connected internally?

No - the exposed pad on the MP3202DG-LF-P QFN8 package is not electrically connected to any internal node. It is a thermal-only pad and must be soldered to a dedicated PCB copper pour for heat dissipation, but must remain isolated from signal or power planes.