Monolithic Power Systems Inc. MPQ7235GQBE-AEC1-Z

Overview

MPQ7235GQBE-AEC1-Z from Monolithic Power Systems is an AEC-Q100 Grade 1 qualified synchronous buck LED driver optimized for infrared (IR) illumination in automotive vision systems. It delivers up to 1.5A continuous and 3A peak LED current across a 4V–36V input range, operates at 2.2MHz switching frequency, supports 10Hz–2kHz PWM dimming, and integrates 85mΩ/50mΩ HS/LS MOSFETs in a wettable-flank QFN-13 (2.5mm×3mm) package for DMS and camera IR lighting.

For engineers reviewing the MPQ7235GQBE-AEC1-Z datasheet, MPQ7235GQBE-AEC1-Z pinout, MPQ7235GQBE-AEC1-Z application, or MPQ7235GQBE-AEC1-Z equivalent, key selection criteria include its AEC-Q100 qualification, 10Hz low-frequency PWM capability for 30/60/120fps synchronization, CISPR25 Class 5 EMI compliance, integrated fault reporting (/FAULT), and thermal shutdown with 150°C trip point.

Technical Context

The MPQ7235GQBE-AEC1-Z implements fixed-frequency peak-current-mode control with valley-current over-current protection and internal soft-start (2ms). Its architecture integrates high-side and low-side power MOSFETs, a bootstrap regulator for HS-FET gate drive, and a precision 200mV feedback reference for LED current regulation via external sense resistor.

It features dedicated fault detection circuitry that asserts open-drain /FAULT on LED short/open conditions or thermal shutdown, and supports FCCM operation during light-load conditions to maintain regulation without audible noise. The DIM pin accepts external PWM signals down to 10Hz with 0.8V typical threshold and 175mV hysteresis.

Key Specifications

Pinout & Package

MPQ7235GQBE-AEC1-Z is housed in a wettable-flank QFN-13 package (2.5mm × 3mm, 0.5mm pitch), enabling automated optical inspection (AOI) of solder joints and enhanced thermal performance via exposed PGND pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar IR LED driver applications.

Compared with MPQ7235GQ-AEC1-Z, the wettable flank variant adds AOI capability without electrical change; versus TPS92692QPWPRQ1, MPQ7235GQBE-AEC1-Z reduces solution size by 40% and eliminates external power stage design effort.

Availability

MPQ7235GQBE-AEC1-Z is available at Aetrix Electronics and suitable for automotive driver monitoring systems, cabin camera illumination, and front-facing ADAS night vision requiring stable component supply with AEC-Q100 traceability and long-term lifecycle support.

Supply support for MPQ7235GQBE-AEC1-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 power management ICs for automotive, industrial, and consumer applications.

The MPQ7235 product line is designed specifically for AEC-Q100-compliant infrared LED driving in automotive vision systems, emphasizing low EMI, frame-synchronized dimming, and robust fault handling in harsh environments.

FAQ

What is the minimum PWM dimming frequency supported by MPQ7235GQBE-AEC1-Z?

The MPQ7235GQBE-AEC1-Z supports PWM dimming frequencies as low as 10Hz, enabling precise synchronization with camera frame rates including 30fps, 60fps, and 120fps. This is achieved through dedicated DIM pin circuitry with 175mV hysteresis and fast turn-on/turn-off response, ensuring clean current transitions even at ultra-low duty cycles.

How does the /FAULT pin indicate LED open-circuit conditions?

The /FAULT pin is an open-drain output pulled low during LED open, short-to-GND, short-to-LED-, or thermal shutdown events. It remains high-impedance otherwise. External pull-up to VCC or logic rail is required; assertion duration matches fault persistence, and recovery occurs after fault removal plus internal debounce delay (~10μs).

Can MPQ7235GQBE-AEC1-Z drive multiple IR LEDs in series?

Yes - the device regulates LED current, not voltage, and supports output voltages up to V_IN − V_SW drop. With 36V max input and typical 0.4V SW saturation, it can drive series strings requiring ≤35.6V forward voltage (e.g., 11× 3.2V IR LEDs at 1.5A), provided thermal design accommodates total power dissipation.

What is the purpose of the BST pin and required external components?

The BST pin supplies the floating gate drive voltage for the internal high-side MOSFET. A ceramic capacitor (typically 0.1μF) must be placed between BST and SW pins. A 20Ω resistor in series with the BST capacitor is strongly recommended to dampen ringing and reduce SW node voltage spikes during switching transitions.

Is the MPQ7235GQBE-AEC1-Z compatible with standard reflow profiles?

Yes - the QFN-13 wettable flank package is rated for JEDEC J-STD-020 moisture sensitivity level (MSL) 1 and supports standard lead-free reflow profiles (peak 260°C). The exposed thermal pad must be soldered to a solid copper pour with ≥4 thermal vias for optimal thermal performance and reliability.

Does the device require an external current-sense resistor?

Yes - the FB pin senses voltage across an external precision current-sense resistor to regulate LED current. For 1.5A output, a 133mΩ, 1% tolerance, 0805-size resistor yields 200mV drop at regulation point. Resistor power rating must exceed I²R losses (e.g., ≥0.5W for 1.5A).

How is thermal performance affected by PCB layout?

Thermal resistance θ_JA drops from 60°C/W (JESD51-7 4-layer board) to 42°C/W on MPS's EVB with optimized layout: 2-oz copper, 83mm×83mm board, and 9 thermal vias under the exposed PGND pad. Poor layout (e.g., isolated pad, no vias) can increase junction temperature by >40°C at 1.5A continuous load.