Monolithic Power Systems Inc. MP4000DS-LF-P

Overview

MP4000DS-LF-P from Monolithic Power Systems is a constant-current LED driver controller for offline high-brightness white LED applications, implementing boundary conduction mode (BCM) with zero-current turn-on, 300 mV current-sense reference voltage, 110 kHz max switching frequency, and hiccup-mode short-circuit protection. It drives an external MOSFET in a floating buck topology for AC/DC LED lighting systems up to 12 W.

For engineers reviewing the MP4000DS-LF-P datasheet, MP4000DS-LF-P pinout, MP4000DS-LF-P application, or MP4000DS-LF-P equivalent, key selection considerations include BCM operation for efficiency and EMI control, external MOSFET drive capability, dual PWM/DC burst dimming interface, thermal shutdown at 150°C, and SOIC8 packaging with 96°C/W θJA.

Technical Context

The MP4000 operates in boundary conduction mode using zero-current detection via drain dv/dt sensing at the DRIVE pin, eliminating freewheeling diode reverse recovery loss and enabling soft MOSFET turn-on. Its peak current regulation relies on a 300 mV ±15 mV CS reference voltage sensed across an external resistor.

Burst dimming is implemented through either a DC voltage (0–2.4 V) applied to DIM or a 100 Hz–2 kHz PWM signal, with BOS pin configuration determining mode-capacitor-to-GND for DC dimming, 300 kΩ resistor-to-GND for PWM. UVLO activates at 7.4 V (rising) with 1 V hysteresis, and thermal shutdown triggers at 150°C with 30°C hysteresis.

Key Specifications

Pinout & Package

MP4000DS-LF-P is housed in an industry-standard SOIC8 package (5.0 mm × 6.2 mm, 1.27 mm pitch), RoHS-compliant, with exposed pad not present and thermal resistance θ_JA = 96°C/W on 4-layer JEDEC PCB.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current offline LED driver controller applications.

Compared with MP4000DS-LF-P, MP4001DS-LF-P reduces component count but sacrifices design flexibility and peak power, while LYT6079C enables isolation compliance at the cost of topology lock-in and loss of BCM control granularity.

Availability

MP4000DS-LF-P is available at Aetrix Electronics and suitable for residential LED downlights, industrial area lighting, and architectural accent lighting requiring stable component supply, long-lifecycle support, and RoHS-compliant manufacturing.

Supply support for MP4000DS-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, founded in 1997 and headquartered in Kirkland, Washington.

The MP4000 belongs to MPS's offline LED driver controller product line, designed specifically for cost-sensitive, non-isolated, high-efficiency AC/DC LED lighting solutions operating in boundary conduction mode.

FAQ

What is the recommended inductor value for MP4000DS-LF-P in a 12 W, 350 mA LED application?

For 90–265 VAC input and 350 mA output at 10–40 V, a 680 µH inductor is validated per the reference design. Inductor value scales inversely with switching frequency and input-output voltage differential; use L = (V_IN – V_OUT) × V_OUT / (2 × f_S × I_LED × V_IN) to recalculate for custom designs.

Can MP4000DS-LF-P operate without a valley-fill PFC circuit?

Yes - MP4000DS-LF-P functions without valley-fill PFC, but power factor will fall below 0.7 in universal AC input applications. The controller itself does not integrate PFC; valley-fill is an external passive network added to meet regulatory PF requirements, not a functional requirement for basic operation.

How is the burst dimming frequency set when using DC voltage control on the DIM pin?

The burst dimming frequency is set by the capacitor connected between BOS and GND: f_DIM ≈ I_BOS / C_BOS, where I_BOS is the BOS pin source current (3–5 µA). A typical 1 nF capacitor yields ~3–5 kHz burst frequency, independent of DIM voltage level, which only controls duty cycle.

Does MP4000DS-LF-P require a minimum load to regulate properly?

No minimum load is required. The controller regulates LED current via peak current sensing and BCM timing; regulation remains stable from 0% to 100% burst dimming duty cycle. However, output short condition triggers hiccup protection, not dropout.

What is the purpose of the TST pin, and how should it be connected?

The TST pin is a factory test terminal with no user-accessible function. Per datasheet guidance, it must be connected directly to GND in all applications to ensure proper internal biasing and avoid undefined behavior or startup failure.

Is MP4000DS-LF-P qualified for automotive lighting applications?

No - MP4000DS-LF-P is specified for -40°C to +85°C ambient operation and lacks AEC-Q100 qualification, automotive-grade screening, or extended temperature range (e.g., -40°C to +125°C junction). It targets residential and industrial lighting, not automotive environments.