Monolithic Power Systems Inc. EVBL9841-L-00A

Overview

EVBL9841-L-00A from Monolithic Power Systems is a fully assembled and tested evaluation board for the MP9841/MPQ9841 synchronous step-down converter, delivering 3.3V at up to 1A across a 3.3V–36V input range. It integrates the MPL-AL6060-100 power inductor, supports AAM/FCCM mode selection via SYNC pin, and features PG indication, configurable soft-start, and 350kHz–2.5MHz switching frequency tuning via external resistor.

For engineers reviewing the EVBL9841-L-00A datasheet, EVBL9841-L-00A pinout, EVBL9841-L-00A application, or EVBL9841-L-00A equivalent, this board enables rapid validation of high-efficiency, low-I_Q DC/DC conversion in automotive and industrial power systems with real-world cold-crank, load-dump, and transient testing capability.

Technical Context

The EVBL9841-L-00A implements the MPQ9841GL (QFN-16, 3mm×3mm) IC with integrated 125mΩ/115mΩ MOSFETs, current-mode control, and valley-current OCP. It operates in AAM mode by default (SYNC floating), reducing f_SW under light load to achieve 14μA quiescent current, and switches to FCCM when SYNC is driven high for fixed-frequency operation.

Board-level design includes an optimized 2.5cm×2.5cm layout with input/output EMC filtering (CIN1–CIN6, C2A–C2D), 4.7nF soft-start capacitor (C3), and test points for VIN, VOUT, EN, SYNC, and PG. The feedback network (R7/R8 = 1MΩ/316kΩ) sets V_OUT = 3.3V, and RFREQ (R4 = 191kΩ) configures f_SW ≈ 450kHz.

Key Specifications

Availability

EVBL9841-L-00A is available at Aetrix Electronics and suitable for automotive infotainment power rails, industrial PLC I/O modules, and connected sensor node designs requiring stable component supply, fast prototyping cycles, and production-ready reference performance.

Supply support for EVBL9841-L-00A 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, with over two decades of innovation in DC/DC converters, motor drivers, and LED controllers.

The MP9841/MPQ9841 product line targets automotive and industrial applications demanding wide VIN, low I_Q, and robust transient response-designed specifically for 12V/24V battery systems with cold-crank resilience and AEC-Q100 qualification support.

FAQ

What input voltage range does the EVBL9841-L-00A support?

The board accepts 3.3V to 36V DC input, validated for automotive battery scenarios including cold-crank (VIN dropping to 3.3V) and load-dump (VIN spiking to 36V). Input filtering uses CIN1–CIN6 ceramic capacitors to suppress transients and ensure stable operation across this full range.

How do I configure the output voltage to 5V?

Replace R7 (1MΩ) and R8 (316kΩ) with RFB1 = 41.2kΩ and RFB2 = 7.68kΩ (per Table 1), maintaining 1% tolerance. The feedback divider sets V_OUT = 0.8V × (1 + RFB1/RFB2); no PCB modification is needed beyond resistor replacement on the FB net.

Can the EVBL9841-L-00A operate in forced continuous conduction mode (FCCM)?

Yes-drive the SYNC pin high (≥1.8V) to enable FCCM. When SYNC is grounded or left floating, the board defaults to Advanced Asynchronous Modulation (AAM) for ultra-low I_Q. FCCM eliminates switching frequency variation under light load, improving EMI predictability.

What is the purpose of the damping capacitor at the input terminals?

A damping capacitor (e.g., 10µF–22µF ceramic) is required at VIN/GND when using cables longer than 0.5m or operating above 24V. It suppresses LC resonance between cable inductance and input capacitance, preventing instability or hiccup-mode triggering during startup or transients.

Does the board include ESD or overvoltage protection on signal pins?

No discrete TVS or ESD protection is integrated on EN, SYNC, or PG pins. These signals are directly connected to the MPQ9841GL's internal circuitry, which provides ±2kV HBM ESD rating per datasheet. External protection must be added if deployed in high-noise environments.

How is power-good (PG) functionality verified on this board?

PG asserts high when V_OUT reaches 90% of target (≥2.97V for 3.3V output) and remains within ±10% regulation. The PG pin drives an open-drain output; users must add a pull-up resistor (e.g., 10kΩ to 5V) to monitor status with logic-level inputs or LEDs.