Monolithic Power Systems Inc. MP3352DQ-LF-P

Overview

MP3352DQ-LF-P from Monolithic Power Systems is a 60V, 2.5A integrated photo-flash charger IC with built-in IGBT driver and quench control for xenon flash systems. It delivers precision charging via critical conduction mode flyback topology, features a 200mΩ internal power switch, 3% charge voltage accuracy (1.20V FB threshold), and supports 3–6V input. Used in compact camera modules where fast capacitor charging and accurate flash timing are required.

For engineers reviewing the MP3352DQ-LF-P datasheet, MP3352DQ-LF-P pinout, MP3352DQ-LF-P application, or MP3352DQ-LF-P equivalent, key selection criteria include peak current programmability (via ISET resistor), integrated IGBT gate drive capability (5Ω pull-up/pull-down), quench sensing interface (QSNS/QREF), RDYB open-drain ready signal, and QFN16-3mm×3mm thermal performance (θJA = 50°C/W).

Technical Context

The MP3352 operates in critical conduction mode (CRM) with peak current control set by external resistor on ISET pin, enabling precise energy delivery to flash capacitors up to 300V. Its internal 60V/200mΩ MOSFET switch minimizes conduction loss while allowing lower transformer turns ratio to reduce leakage-induced switching loss.

Integrated analog functions include a 1.20V FB comparator with ±24mV tolerance, DCM detection using 25mV offset, thermal shutdown at 150°C (15°C hysteresis), and quench control via QSNS/QREF differential sensing to terminate flash exposure based on phototransistor feedback - all implemented without external op-amps or timers.

Key Specifications

Pinout & Package

MP3352DQ-LF-P is housed in a thermally enhanced 16-pin QFN package (3mm × 3mm, exposed thermal pad), rated for –40°C to +85°C ambient operation. The exposed pad must be soldered to PCB ground plane for optimal thermal performance (θJC = 12°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar xenon flash charger applications.

Compared with MAX8640Y and TPS65120, MP3352DQ-LF-P uniquely integrates CRM control, 60V switch, IGBT driver, and quench sensing - enabling single-chip xenon flash systems with adaptive exposure, whereas alternatives require ≥3 extra components and lack timing-critical quench functionality.

Availability

MP3352DQ-LF-P is available at Aetrix Electronics and suitable for digital still cameras, optical film cameras, mobile phones with camera, and PDAs with camera requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.

Supply support for MP3352DQ-LF-P 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, founded in 1997 and headquartered in Kirkland, Washington.

The MP3352 belongs to MPS's photo-flash power management product line, engineered specifically for compact, battery-powered imaging devices requiring fast, accurate, and intelligent xenon flash charging with exposure control.

FAQ

What is the maximum flash capacitor voltage supported by MP3352DQ-LF-P?

The MP3352DQ-LF-P regulates output voltage via feedback divider to 300V in typical applications, enabled by its 60V SW pin rating and CRM flyback architecture. While the internal switch withstands 60V, the transformer steps this to 300V; exceeding 300V risks overvoltage on FB network resistors and may violate safety margins in certified camera designs.

How is peak charge current set, and what resistor value gives 2.5A?

Peak current is set by resistor R_SET from ISET pin to GND using I_PEAK = 50 kΩ / R_SET(kΩ). For 2.5A, R_SET = 20 kΩ (e.g., 20.0kΩ ±1%). The datasheet confirms 1.36–1.66A with 33.2kΩ and 0.4–0.6A with 100kΩ, validating the linear relationship and tolerance stack-up.

Does MP3352DQ-LF-P support automatic flash exposure control?

Yes - via its dedicated quench function using QREF and QSNS pins. When QSNS voltage (from phototransistor) exceeds QREF, the internal comparator disables IGBTOUT within 2µs, terminating flash exposure. This closed-loop method replaces mechanical shutters or fixed-timing circuits in optical film and DSLR cameras.

What is the purpose of the two PGND pins (pins 7 and 8)?

Pins 7 and 8 are paralleled power ground terminals for the high-current SW node and IGBT driver return path. They must be connected to a low-inductance, wide copper pour tied to the exposed thermal pad. Separating PGND from AGND (pin 2) prevents switching noise from corrupting FB, QSNS, and QREF analog measurements.

Can MP3352DQ-LF-P operate from a single-cell Li-ion battery?

Yes - its 3–6V VIN range covers discharged (3.0V) to fully charged (4.2V) single-cell Li-ion. The 2.7–2.9V UVLO ensures reliable startup above battery cutoff, and 50µA quiescent current during charge-complete state preserves runtime. Typical charge time for 47µF is ~400ms at 3.3V input.

Is RDYB an active-high or open-drain output, and how should it be used?

RDYB is an open-drain output that pulls low when FB ≥ 1.20V (flash capacitor charged). It requires an external pull-up resistor (e.g., 10kΩ to VIN) to generate a logic-high signal. System MCU reads RDYB to synchronize IGBTIN assertion and avoid premature flash firing before full charge.

What transformer specifications are recommended for 2.5A peak current?

MPS recommends transformers with 1:8 turns ratio, 6µH primary inductance, and ≥600V isolation - e.g., TOKYO Coil TTRN-038S or Wurth 750310448. These match the 300ns minimum off-time requirement and handle 2.5A peak without saturation, ensuring stable CRM operation and minimal audible noise.