Monolithic Power Systems Inc. EVM3810-QB-33-01A

Overview

EVM3810-QB-33-01A from Monolithic Power Systems is a fixed-output 3.3V, 1.2A peak synchronous step-down DC-DC power module with integrated inductor and MOSFETs in a QFN-12 (2.5mm × 3.0mm × 0.9mm) package. It operates from 2.5V to 6V input, delivers regulated output down to 0.6V (fixed at 3.3V for this variant), features constant-on-time control, 17μA quiescent current, and built-in PG, EN, thermal shutdown, and hiccup-mode short-circuit protection - deployed in space-constrained portable instruments and SSD/HDD power rails.

For engineers reviewing the EVM3810-QB-33-01A datasheet, EVM3810-QB-33-01A pinout, EVM3810-QB-33-01A application, or EVM3810-QB-33-01A equivalent, key selection criteria include verified 3.3V ±3% output accuracy at 10mA, 2.1A cycle-by-cycle current limit, 3.5MHz typical switching frequency, and QFN-12 thermal performance with θJA = 65°C/W on 4-layer PCB - critical for low-noise, high-density embedded power design.

Technical Context

The EVM3810-QB-33-01A implements constant-on-time (COT) control with input-voltage feedforward to maintain stable ~3.5MHz switching across 2.5–6V input and 3.3V output, eliminating loop compensation components. Its internal 0.47μH inductor and matched 100mΩ/60mΩ P/N-FET pair enable fast transient response and high light-load efficiency via DCM operation triggered by zero-current detection.

Power sequencing is supported by an open-drain PG pin with ±10% regulation window and 50μs delay, while EN logic thresholds (1.2V high / 0.4V low) and 1.5ms soft-start ensure controlled startup. Protection includes thermal shutdown at 150°C with 30°C hysteresis, cycle-by-cycle current limiting, and hiccup-mode recovery from short circuits.

Key Specifications

Pinout & Package

Package: QFN-12 (2.5mm × 3.0mm × 0.9mm) with exposed thermal pad (pins 3–4 connected internally to SW node and tied to copper pour for heat dissipation).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSM1033W and RT6220BGQW, EVM3810-QB-33-01A uniquely combines 1.2A capability, 3.5MHz operation, PG/EN sequencing, remote sensing (OUT_S), and integrated inductor in a 7.5mm² footprint - making it optimal for compact, high-reliability embedded systems requiring precise power control.

Availability

EVM3810-QB-33-01A is available at Aetrix Electronics and suitable for portable instrumentation, SSD/HDD interface power, and FPGA I/O bank supply requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for EVM3810-QB-33-01A 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, headquartered in Kirkland, WA, with global design and support centers.

The MPM3810 product line delivers fully integrated, easy-to-use DC-DC power modules targeting space- and efficiency-critical applications in portable electronics, storage, and industrial embedded systems.

FAQ

What is the maximum allowable input voltage for EVM3810-QB-33-01A?

The absolute maximum input voltage is 6.5V, but the recommended operating range is 2.5V to 6V. Exceeding 6V risks permanent damage to internal MOSFETs and control circuitry, as confirmed by MPS Absolute Maximum Ratings table. Operation above 6V voids warranty and triggers immediate thermal shutdown.

Does EVM3810-QB-33-01A require external feedback resistors?

No - EVM3810-QB-33-01A is the fixed 3.3V output variant (MPM3810GQB-33), so the FB pin is NC (no-connect). Only input and output ceramic capacitors are required, per the datasheet's ordering information and typical application schematic.

How does the PG (Power Good) pin function in this module?

PG is an open-drain output with a 550kΩ internal pull-up to VIN. It asserts high when the FB voltage (internally referenced to 0.6V) falls within ±10% of 3.3V (i.e., 3.0–3.6V), with a 50μs delay. If regulation drifts outside that window, PG pulls low via an internal MOSFET with <400Ω R_DS(on).

Can EVM3810-QB-33-01A operate in dropout mode?

Yes - it supports 100% duty cycle operation, allowing regulation down to V_IN – V_DR, where dropout resistance R_DR is 220mΩ. At 1.2A load, dropout voltage is ~264mV, enabling usable output even when input drops to ~3.56V while maintaining 3.3V.

What thermal derating applies at 85°C ambient temperature?

With θ_JA = 65°C/W on a 4-layer PCB, junction temperature rise at 1.2A is ~78°C. At 85°C ambient, T_J reaches ~163°C - exceeding the 150°C shutdown threshold. Derate to ≤0.95A at 85°C ambient to stay within safe operating limits, per thermal resistance calculations in the datasheet.

Is the OUT_S pin mandatory for stable operation?

No - OUT_S is optional for remote sensing. When unused, tie it directly to the OUT pin. Using OUT_S improves load regulation accuracy by compensating for PCB trace resistance (up to 50mΩ), especially critical in high-current or long-trace applications like SSD backplanes.

What is the minimum output capacitance required for stability?

The datasheet specifies 20μF ceramic (X5R/X7R) as the recommended output capacitor. Lower values (e.g., 10μF) may cause instability or excessive ripple (>30mVpp) under dynamic load, as validated in Typical Performance Characteristics plots on page 6–11 of Rev. 1.1.