Monolithic Power Systems Inc. EVQ4313-R-01A

Overview

EVQ4313-R-01A from Monolithic Power Systems is a fully assembled, AEC-Q100 Grade 1 qualified evaluation board for the MPQ4313 synchronous step-down converter. It demonstrates 3A output capability across a 3.3V–45V input range, features frequency spread spectrum (FSS), configurable switching frequency (410 kHz default), and supports automotive cold-crank and load-dump conditions with low 1.7μA shutdown quiescent current.

For engineers reviewing the EVQ4313-R-01A datasheet, EVQ4313-R-01A pinout, EVQ4313-R-01A application, or EVQ4313-R-01A equivalent, this board enables rapid validation of MPQ4313 performance in AEC-Q100-compliant power systems-including start-up behavior under VIN ramping, PG signaling, SYNCIN synchronization (350–1000 kHz), and FCCM/AAM mode selection.

Technical Context

The EVQ4313-R-01A implements the MPQ4313 IC in a QFN-20 (4mm × 4mm) wettable flank package, integrating high-side and low-side MOSFETs, current-mode control, and thermal shutdown. It supports dual operating modes-Forced Continuous Conduction Mode (FCCM) and Auto-Discontinuous Mode (AAM)-with configurable soft-start (1.6 ms via 10 nF CSS) and external frequency synchronization.

Board-level design includes EMI mitigation (CISPR25 Class 5 compliant conducted/radiated emissions), input EMI filtering (L1 + CIN1–CIN4), and precision output voltage setting via R7/R8 resistor divider (e.g., 3.3 V with 100 kΩ/32.4 kΩ). The PG pin provides power-good indication with ±7%/+6% window, and MODE pin selects FCCM (pin 2–3) or AAM (pin 2–1).

Key Specifications

Availability

EVQ4313-R-01A is available at Aetrix Electronics and suitable for automotive ADAS domain controllers, infotainment head units, and body electronics requiring stable component supply, AEC-Q100 validation support, and fast-turn evaluation of high-efficiency buck conversion.

Supply support for EVQ4313-R-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 power management ICs for automotive, industrial, cloud computing, and consumer applications.

The MPQ4313 product line delivers AEC-Q100-qualified DC/DC converters optimized for harsh automotive environments-featuring wide VIN range, low IQ, thermal robustness, and integrated protection for reliable operation in engine control, lighting, and telematics systems.

FAQ

What is the default output voltage and how is it set?

The EVQ4313-R-01A is configured for 3.3 V output using a 100 kΩ (R7) and 32.4 kΩ (R8) resistor divider per the MPQ4313's 0.815 V reference. Output voltage is calculated as VOUT = 0.815 V × (1 + R7/R8); alternative values (e.g., 5 V) are supported by changing R8 to 19.1 kΩ while retaining R7 = 100 kΩ.

How do I enable or disable the MPQ4313 on this board?

Drive the EN pin above 1 V to enable regulation and below 0.85 V to enter shutdown mode. The board exposes EN via a 1 mm golden pin (JP1 pin 2); no external pull-up is required-the IC has an internal 2 MΩ pull-down. EN assertion initiates soft-start and activates PG after regulation is established.

Can I synchronize the switching frequency to an external clock?

Yes-apply a 350 kHz to 1000 kHz square wave to the SYNCIN pin (JP1 pin 3). The MPQ4313 locks its internal oscillator to the rising edge of the external signal. When synchronized, SYNCO (JP1 pin 4) outputs a buffered copy of the internal clock for cascaded timing control.

What protection features are demonstrated on this board?

The board validates overcurrent protection (SCP entry/recovery in <20 ms), thermal shutdown (case temperature rise ≤14 °C at 3 A), input undervoltage lockout (UVLO), and PG fault signaling. Load-dump (12 V → 36 V) and cold-crank (12 V → 3.3 V) transients are tested per ISO 16750-2 with stable VOUT regulation.

Is the board pre-configured for FCCM or AAM mode?

By default, the MODE jumper (JP1 pins 2–1) configures the MPQ4313 for AAM (Auto-Discontinuous Mode) to maximize light-load efficiency. To force FCCM, short JP1 pins 2–3. Mode selection affects efficiency curves, ripple, and audible noise-verified in test reports across 10 mA–3 A loads.

Does the board include EMI filtering components?

Yes-the board integrates a 30 mΩ ferrite bead (L1), ceramic input capacitors (CIN1–CIN4), aluminum bulk capacitor (CIN5), and layout-optimized ground planes to meet CISPR25 Class 5 conducted/radiated emission limits. Damping capacitor installation is recommended for input cables >0.5 m when VIN ≥24 V.

What is the purpose of the "NS" components listed in the BOM?

"NS" (Not Stuffed) components-C2C, C2D, and R2-are unpopulated placeholders for optional functionality: C2C/C2D support additional output capacitance or damping networks; R2 enables optional current-sense resistor placement for IL monitoring. These are omitted in standard configuration but available for custom validation.