Monolithic Power Systems Inc. MEZD71202A-B

Overview

MEZD71202A-B from Monolithic Power Systems is a 2A, synchronous step-down DC/DC power supply module with 4.5V–24V input range, fixed 1.2V output, ±2.5% output voltage accuracy, 400kHz switching frequency, and hiccup-mode short-circuit protection. It integrates power MOSFETs, inductor, and compensation circuitry, targeting space-constrained industrial and embedded power rails.

For engineers reviewing the MEZD71202A-B datasheet, MEZD71202A-B pinout, MEZD71202A-B application, or MEZD71202A-B equivalent, key selection criteria include input voltage headroom (VIN > VOUT +1V), thermal derating above 45°C, load regulation (±1% typ.), and compatibility with 0402/0805/1206 passive footprints in DIY layouts.

Technical Context

This module implements a fully integrated buck converter architecture with internal high-side and low-side MOSFETs, fixed-frequency current-mode control, and internal compensation. It supports adjustable soft-start via external capacitor on the EN pin and delivers regulated 1.2V at up to 2A continuous load under -40°C to +85°C ambient conditions.

Protection features include over-temperature shutdown at 150°C, hiccup-mode short-circuit response, and over-/under-voltage lockout. Input-to-output isolation is not provided; it is a non-isolated point-of-load regulator requiring external input capacitance (≥2.2µF) and output capacitance (≥22µF).

Key Specifications

Pinout & Package

FCQFN3x3-16 package with exposed thermal pad (bottom side); 3.0mm × 3.0mm footprint, 0.5mm pitch, 0.8mm max height. Pin 1 marked by dot; pins 1–3 and 14–16 are signal I/O; pins 4–13 are GND/VIN/VOUT power planes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MPM3530, MEZD71202A-B offers identical pinout and layout but lower efficiency and no updated qualification; compared with TSM12202, it provides superior fault resilience via hiccup mode and lower output noise, at the cost of slightly larger solution size.

Availability

MEZD71202A-B is available at Aetrix Electronics and suitable for industrial PLC I/O modules, embedded vision sensor nodes, medical patient monitor front-ends, and automotive body control modules requiring stable component supply despite end-of-life status.

Supply support for MEZD71202A-B 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 power management ICs and modules, headquartered in Kirkland, WA, with global design and support centers.

The mEZD71202A series belongs to MPS's ready-to-use DC/DC module product line, engineered for rapid deployment in space-constrained industrial and embedded systems where layout simplicity and time-to-market are critical.

FAQ

Is MEZD71202A-B still in production?

No - MEZD71202A-B is officially End-of-Life per MPS documentation. Aetrix Electronics maintains limited legacy stock and supports last-time buys with full traceability. New designs should migrate to the pin-compatible MPM3530, which shares the same FCQFN3x3-16 package and 1.2V output option.

What is the minimum input voltage required for 1.2V output regulation?

The datasheet specifies VIN must exceed VOUT by at least 1V for regulation. Therefore, the minimum valid input is 2.2V - however, the absolute minimum rated input is 4.5V. Operation below 4.5V is not guaranteed and may result in dropout or instability.

Can MEZD71202A-B be used without the recommended 22µF output capacitor?

No - the 22µF X7T/X5R ceramic capacitor is required for stability and ripple suppression. Omitting it causes loop instability, excessive output voltage deviation (>±5%), and potential oscillation. Two 22µF 0805 caps in parallel meet the specification and improve thermal distribution.

Does MEZD71202A-B support remote sensing?

No - MEZD71202A-B has no dedicated sense pins and uses single-point feedback. Voltage drop across PCB traces will cause load regulation error; keep VOUT and GND traces short and wide (<50mΩ total resistance) to maintain ±1% load regulation.

What is the purpose of the NC pins (14–16)?

Pins 14–16 are No-Connect terminals - they are not internally bonded and serve only mechanical alignment and thermal dissipation roles. They must remain unconnected in PCB layout; no vias, traces, or solder mask openings are permitted on these pads.

How does hiccup-mode protection behave during sustained short-circuit?

Upon short-circuit detection, MEZD71202A-B disables switching, waits ~100ms, then attempts restart. If the fault persists, it repeats this cycle indefinitely - preventing thermal damage while enabling automatic recovery if the short is transient or intermittent.

Is the thermal pad electrically connected to GND?

Yes - the exposed thermal pad on the bottom of the FCQFN3x3-16 package is internally connected to the power ground (GND) plane. It must be soldered to a solid copper thermal pad tied directly to the main system GND for both thermal performance and electrical integrity.