Monolithic Power Systems Inc. MP28252EL-LF-Z

Overview

MP28252EL-LF-Z from Monolithic Power Systems is a synchronous step-down DC-DC converter with integrated 190mΩ high-side and 60mΩ low-side MOSFETs, delivering up to 2A continuous output current across a 4.5V–21V input range. It operates at a fixed 500kHz switching frequency (syncable from 300kHz to 2MHz), features internal compensation, 0.805V feedback reference, and power-good monitoring - optimized for compact I/O power in notebook and flat-panel display systems.

For engineers reviewing the MP28252EL-LF-Z datasheet, MP28252EL-LF-Z pinout, MP28252EL-LF-Z application, or MP28252EL-LF-Z equivalent, key selection criteria include its 14-pin QFN package thermal performance (θJA = 48°C/W), 150°C thermal shutdown threshold, OCP trip point of 3–4A, and EN/SYNC dual-function pin behavior under TTL/CMOS logic or external clock synchronization.

Technical Context

The MP28252 employs peak-current-mode control with an internal 500kHz oscillator and proprietary switching loss reduction. Its error amplifier compares FB voltage against a trimmed 0.805V reference and drives an internal compensation network, eliminating external loop components.

It integrates a 5V VCC regulator powered from VIN, bootstrap circuitry for high-side gate drive, and a dedicated open-drain PG pin asserting low when output falls below 0.85×VFB. UVLO activates at 4.0V rising threshold with 880mV hysteresis, and soft-start ramps over 4ms to limit inrush.

Key Specifications

Pinout & Package

The MP28252EL-LF-Z is housed in a thermally enhanced 3mm × 4mm, 14-pin QFN package with an exposed thermal pad on the underside, requiring solder connection to PCB ground plane for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with RT6220AGQW and TPS54202DDCR, the MP28252EL-LF-Z uniquely combines 21V input support, SYNC capability, and PG monitoring in a 3×4mm QFN - making it optimal for space-constrained, multi-rail consumer electronics where thermal management and system-level timing coordination are critical.

Availability

MP28252EL-LF-Z is available at Aetrix Electronics and suitable for notebook I/O power, flat-panel display bias, and distributed networking power requiring stable component supply, RoHS-compliant packaging, and consistent lead-time visibility.

Supply support for MP28252EL-LF-Z 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 global manufacturing partnerships.

The MP28252 belongs to MPS's high-density DC-DC converter product line, engineered specifically for space-constrained consumer and computing applications demanding high efficiency, small footprint, and robust protection features.

FAQ

What is the minimum recommended input capacitance for MP28252EL-LF-Z?

A 22µF X5R/X7R ceramic capacitor is recommended at the IN pin, placed as close as possible to pins 1 and 11–14. This value ensures adequate RMS current handling (≥1A) and limits input ripple voltage to <100mV under 2A load. For high-reliability designs, paralleling with a 0.1µF capacitor improves high-frequency decoupling.

Can MP28252EL-LF-Z operate with an output voltage lower than 0.805V?

No - the internal reference is fixed at 0.805V, and the FB pin is designed to regulate only at or above this voltage. Output voltages below 0.805V cannot be achieved using standard resistor-divider feedback. For sub-0.8V outputs, a different converter with adjustable reference or external reference injection would be required.

How does the EN/SYNC pin behave when used for external clock synchronization?

When an external clock signal (300kHz–2MHz) is applied to EN/SYNC, the MP28252 locks its internal oscillator to the external edge within 2ms. The chip remains enabled only if the external clock is present and stable; loss of clock causes automatic shutdown after timeout. No pull-up/down resistors are needed in sync mode.

Is the exposed thermal pad electrically connected internally?

No - the exposed pad has no internal electrical connection and must be soldered exclusively to the PCB ground plane. It serves only for thermal conduction and mechanical anchoring. Connecting it to any other net risks short circuits or degraded thermal performance due to insufficient solder wetting.

What happens during output short-circuit condition?

Under sustained short-circuit, the MP28252 enters hiccup mode: it cycles between brief startup attempts (~100ms intervals) and shutdown. This limits average short-circuit current to ~500mA, preventing thermal runaway. Recovery is automatic once the fault is removed and FB rises above 0.85×VFB.

Does MP28252EL-LF-Z require an external bootstrap diode?

An external bootstrap diode (e.g., IN4148) is optional and recommended only when duty cycle exceeds 65% (i.e., VOUT > 0.65×VIN). At lower duty cycles, the internal bootstrap circuit provides sufficient gate drive. Adding the diode improves efficiency by ~0.5–1% under heavy load but adds cost and board area.

What is the maximum allowable output capacitor ESR for stable operation?

The MP28252 is optimized for ceramic output capacitors with ESR < 10mΩ. While it tolerates higher ESR (e.g., tantalum up to 50mΩ), doing so increases output ripple and may degrade phase margin. For best stability and transient response, use X5R/X7R ceramics with total ESR ≤ 5mΩ and ≥47µF capacitance.