Monolithic Power Systems Inc. MP3213DH-LF

Overview

MP3213DH-LF from Monolithic Power Systems is a current-mode synchronous boost DC-DC converter with an integrated 3.5A/0.18Ω 25V N-channel MOSFET switch, fixed 700kHz or 1.3MHz switching frequency (pin-selectable), 1.25V feedback reference, and programmable soft-start. It operates from 2.5V–22V input to deliver up to 12V/500mA from a 5V source and includes UVLO, thermal shutdown, and internal current limiting. Used in portable LCD bias supplies.

For engineers reviewing the MP3213DH-LF datasheet, MP3213DH-LF pinout, MP3213DH-LF application, or MP3213DH-LF equivalent, key selection criteria include input voltage range (2.5V–22V), output voltage capability (up to 22V), peak switch current rating (3.5A), thermal performance (θJA = 80°C/W in MSOP8), and FSEL-configurable switching frequency for EMI-sensitive designs.

Technical Context

The MP3213DH-LF implements constant-frequency peak-current-mode control with an internal transconductance error amplifier (GEA = 350 μmho, AVEA = 1000 V/V) and external compensation via COMP pin. Its architecture supports stable regulation across wide duty cycles (up to 95%) while maintaining loop stability with ceramic output capacitors.

It features dual-frequency operation selected by FSEL pin logic level (GND = 700kHz, IN = 1.3MHz), programmable soft-start via SS pin (6μA charge current), and precise 1.25V ±2.5% feedback reference with –200nA to –100nA input bias current - enabling accurate output voltage setting with high-side resistor tolerance independence.

Key Specifications

Pinout & Package

The MP3213DH-LF is housed in an 8-pin MSOP package with exposed thermal pad (JEDEC MO-187, variation AA-T), offering θ_JA = 80°C/W and θ_JC = 12°C/W for effective power dissipation in space-constrained layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar boost converter applications.

Compared with MP3213DQ-LF, the MP3213DH-LF trades thermal margin for smaller MSOP8 footprint and lower assembly cost; versus TPS61088RHLR, it offers frequency selection and soft-start programmability at the expense of slightly narrower input range and higher quiescent current.

Availability

MP3213DH-LF is available at Aetrix Electronics and suitable for LCD display bias supplies, portable medical instrumentation, digital camera auxiliary power, and handheld industrial scanner designs requiring stable component supply with RoHS-compliant packaging and full traceability.

Supply support for MP3213DH-LF 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 mixed-signal ICs for power management, motion control, and automotive applications.

The MP3213 belongs to MPS's high-efficiency boost converter product line, designed specifically for space-constrained portable electronics requiring wide input range, high output voltage, and robust protection features.

FAQ

What is the maximum output voltage achievable with MP3213DH-LF?

The MP3213DH-LF supports output voltages up to 22V, limited by its 25V-rated internal MOSFET and absolute maximum SW pin rating. Practical maximum depends on external components: Schottky diode reverse voltage rating, output capacitor voltage rating, and loop stability at high duty cycles. For 12V output from 5V input, typical efficiency exceeds 85% at 500mA load.

Can MP3213DH-LF operate with input voltage below 2.5V?

No - the absolute minimum recommended operating input voltage is 2.5V per datasheet specifications. Below this, undervoltage lockout activates (UVLO rising threshold = 2.45V), disabling the regulator. Attempting operation below 2.5V risks unstable switching, reduced efficiency, or failure to regulate. For sub-2.5V inputs, consider ultra-low-V_IN boost converters like the MP3221.

How does FSEL pin configuration affect efficiency and thermal performance?

FSEL selection changes switching frequency but not intrinsic efficiency ceiling. At 1.3MHz, smaller inductors/capacitors reduce board area but increase core losses and AC resistance losses - potentially lowering peak efficiency by 1–2% versus 700kHz at medium loads. Thermally, higher frequency increases switching losses, raising junction temperature under identical conditions; however, the MSOP8 package's θ_JA dominates overall thermal rise.

Is an external Schottky diode mandatory for MP3213DH-LF operation?

Yes - the MP3213DH-LF uses asynchronous boost topology and requires an external Schottky diode (e.g., RB055LAM-40) connected between SW and VOUT. The diode provides the freewheeling path when the internal MOSFET is off. Using a slow-recovery or high-V_F diode degrades efficiency and may cause thermal overstress; Schottky selection must meet ≥VOUT reverse voltage rating and ≥3.5A peak current capability.

What is the purpose of the COMP pin, and how is it used in compensation design?

The COMP pin is the output of the internal transconductance error amplifier and serves as the control node for loop compensation. A series RC network (R3–C3) from COMP to GND sets dominant pole and zero locations to stabilize the control loop. Ceramic output capacitors require only this single network; Table 1 in the datasheet provides recommended R3/C3 values based on V_IN, V_OUT, and C_OUT to achieve >45° phase margin and minimal output overshoot during load transients.

Does MP3213DH-LF support automatic restart after thermal shutdown?

Yes - the device features auto-recovery thermal shutdown. When junction temperature exceeds 160°C, the IC disables switching and enters thermal shutdown. Once the die cools below the hysteresis threshold (~140°C), normal operation resumes automatically without requiring EN pin toggling or power cycle. This behavior protects against permanent damage during transient overloads or inadequate heatsinking.

How is output voltage accuracy affected by FB pin bias current?

The FB pin draws –200nA to –100nA (sinking) bias current, which introduces a small offset error in the feedback divider. For a standard 10kΩ bottom resistor (R2), this creates ~0.2–0.4mV error at the FB node - negligible relative to the 1.25V reference (0.03% effect). To minimize impact, keep total divider impedance ≤200kΩ; higher values increase sensitivity to bias current and noise coupling.