Monolithic Power Systems Inc. MP3304CDD-LF-P

Overview

MP3304CDD-LF-P from Monolithic Power Systems is a 36V, 1.3A step-up white LED driver with true PWM dimming up to 50kHz, fixed 2.2MHz switching frequency, and 200mV feedback voltage for high-efficiency current regulation in backlighting applications. It integrates a 1.3A internal MOSFET switch, supports up to 10 parallel LED strings (e.g., 3×10 WLEDs), and features open-load shutdown at 20V OVP.

For engineers reviewing the MP3304CDD-LF-P datasheet, MP3304CDD-LF-P pinout, MP3304CDD-LF-P application, or MP3304CDD-LF-P equivalent, key selection criteria include its 20V over-voltage protection threshold, QFN8 (2×3mm) thermal performance, 250Hz–50kHz PWM dimming range, and compatibility with single-cell Li-ion or 5V input sources in space-constrained portable displays.

Technical Context

The MP3304CDD-LF-P employs constant-frequency peak-current-mode boost control to regulate LED string current via an external sense resistor, with error amplifier feedback referenced to a precise 200mV internal voltage. Its 2.2MHz switching frequency enables compact magnetics and low output ripple.

It implements dual-stage protection: open-circuit detection triggers shutdown when output exceeds 20V (MP3304C variant), while integrated UVLO (2.45V rising threshold), thermal shutdown (150°C), and 1.3A current limiting safeguard operation under fault conditions.

Key Specifications

Pinout & Package

MP3304CDD-LF-P is housed in an 8-pin QFN package (2mm × 3mm, 0.5mm pitch) with exposed thermal pad connected to GND for optimal heat dissipation. The package meets JEDEC MO-229 VCED-2 standards and supports reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP3304BDD-LF-Z, MP3304CDD-LF-P offers tighter OVP margin for lower-V_f LED arrays, reducing risk of nuisance shutdown; versus RT9397BZSP, it delivers integrated safety and lower V_FB for higher accuracy without external parts.

Availability

MP3304CDD-LF-P is available at Aetrix Electronics and suitable for LCD panels, digital picture frames, handheld computers and PDAs, and digital still cameras requiring stable component supply, RoHS-compliant packaging, and guaranteed long-term availability.

Supply support for MP3304CDD-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 mixed-signal ICs for power management, motor drive, and LED lighting applications.

The MP3304 product line delivers highly integrated, thermally robust boost LED drivers optimized for portable and space-constrained backlighting systems with stringent efficiency and reliability requirements.

FAQ

What is the maximum number of white LEDs the MP3304CDD-LF-P can drive?

The MP3304CDD-LF-P supports up to 10 parallel strings of white LEDs. Each string may contain up to 3 series-connected WLEDs (total forward voltage ≤20V) when powered from 5V input. Driving more than 3 in series risks exceeding the 20V OVP threshold and triggering shutdown.

Does MP3304CDD-LF-P require an external Schottky diode?

Yes - the MP3304CDD-LF-P requires an external Schottky diode (e.g., B0530 or B0540) connected between SW and the LED anode. The IC integrates only the high-side MOSFET switch; the diode provides the freewheeling path during switch-off cycles and must handle ≥500mA peak current.

How is LED current set on MP3304CDD-LF-P?

LED current is set by a single external resistor (R_SET) connected between ISET and GND. The IC regulates voltage across R_SET to 200mV (typ.), so I_LED = 0.2V / R_SET. For 200mA output, use R_SET = 1.0Ω (1% tolerance); values are confirmed in Table 1 of the datasheet.

Can MP3304CDD-LF-P operate from a 3.3V input source?

No - the MP3304CDD-LF-P has a minimum input voltage of 3.0V, but its recommended operating range starts at 3V with derated performance. At 3.3V input, output headroom for driving even 3-series WLEDs (≈9.9V) becomes marginal due to 20V OVP and efficiency drop; 5V input is strongly recommended for full functionality.

What thermal design guidance applies to the QFN8 package?

The exposed thermal pad must be soldered to a ≥200mm² solid copper GND plane using ≥4 thermal vias (0.3mm diameter, spaced ≤2mm apart). This achieves the specified θ_JA = 65°C/W. Without proper pad connection, junction temperature may exceed 125°C at 200mA load, triggering thermal shutdown.

Is MP3304CDD-LF-P compatible with I²C or analog dimming interfaces?

No - MP3304CDD-LF-P supports only true PWM dimming via square-wave signals applied to the EN pin (250Hz–50kHz). It does not include I²C registers, analog voltage inputs, or current-source dimming capability. Dimming resolution is controlled solely by PWM duty cycle.

What happens during an open LED string condition?

When an LED string opens, feedback voltage drops to zero, causing the controller to increase duty cycle until output voltage reaches 20V. At that point, the internal OVP circuit triggers shutdown - SW stops switching, and the part remains latched off until input power is cycled. This prevents overvoltage damage to the diode and output capacitor.