Monolithic Power Systems Inc. MP2365DN-LF-P

Overview

MP2365DN-LF-P from Monolithic Power Systems is a 3A, 28V input, 1.4MHz synchronous step-down DC/DC converter with integrated 100mΩ high-side MOSFET and 10Ω low-side switch, delivering adjustable output from 0.92V to 21V in an SOIC-8EP package. It supports distributed power systems and battery chargers with cycle-by-cycle over-current protection, thermal shutdown, and 20μA shutdown current.

For engineers reviewing the MP2365DN-LF-P datasheet, MP2365DN-LF-P pinout, MP2365DN-LF-P application, or MP2365DN-LF-P equivalent, key selection criteria include its 4.75–28V input range, 3A continuous output capability, fixed 1.4MHz switching frequency, programmable soft-start via external capacitor, and compatibility with low-ESR ceramic output capacitors.

Technical Context

The MP2365DN-LF-P employs current-mode control architecture with internal transconductance error amplifier (G_EA = 330–730 µA/V) and slope-compensated current sensing (G_CS = 6.0 A/V), enabling fast transient response and stable loop compensation via the COMP pin. Its bootstrap gate drive (BS pin) powers the high-side N-MOSFET using a SW-to-BS capacitor, supported by an internal 10Ω low-side switch for reliable boot capacitor charging.

It integrates fault protection including cycle-by-cycle current limiting (6.5A typical), thermal shutdown at 160°C, and under-voltage lockout with 210mV hysteresis. The EN pin provides digital enable/disable control with 0.9–1.5V turn-on threshold and 2.3–2.9V lockout, while SS pin sets soft-start duration (e.g., 5ms with 0.1µF).

Key Specifications

Pinout & Package

The MP2365DN-LF-P is housed in an 8-pin SOIC package with exposed thermal pad (SOIC-8EP), JEDEC MS-012 BA compliant, requiring connection of the exposed pad to Pin 4 (GND) for optimal thermal performance and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down converter applications.

Compared with MP2365DN-LF-P, MP2365DN-LF-Z offers identical performance in tape-and-reel format for volume manufacturing, while MP2367DJ-LF-Z delivers 6A capability in a smaller QFN package-requiring PCB rework but enabling higher power density where thermal headroom is limited.

Availability

MP2365DN-LF-P is available at Aetrix Electronics and suitable for industrial distributed power, battery charging systems, pre-regulator for LDOs, and automotive aftermarket electronics requiring stable component supply and long-term sourcing continuity.

Supply support for MP2365DN-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, headquartered in California and serving global industrial, automotive, and computing markets since 1997.

The MP2365 belongs to MPS's high-efficiency DC/DC converter product line, designed specifically for compact, high-current step-down applications where wide input range, low quiescent current, and robust protection are critical in space-constrained environments.

FAQ

What is the maximum recommended output current for MP2365DN-LF-P at +85°C ambient?

The MP2365DN-LF-P delivers 3A continuous output current over –40°C to +85°C ambient, provided the PCB uses adequate copper area on the exposed pad and ground plane per MPS layout guidelines. At +85°C, derating may apply if thermal resistance exceeds 50°C/W; actual current depends on VIN, VOUT, and airflow.

Can MP2365DN-LF-P operate with a 3.3V input supply?

No - the MP2365DN-LF-P has a minimum input voltage of 4.75V per its Absolute Maximum Ratings and Recommended Operating Conditions. Attempting operation below 4.75V will cause UVLO activation and prevent regulation; it is not suitable for 3.3V input-to-lower-VOUT applications.

Is an external bootstrap diode required for standard operation?

An external bootstrap diode (e.g., IN4148) is optional and recommended only when VOUT ≥ 3.3V and duty cycle exceeds 65% (i.e., VOUT/VIN > 0.65). For typical 12V→3.3V or 12V→5V designs, the internal bootstrap switch suffices; the external diode improves efficiency under high-duty-cycle conditions.

How is output voltage accuracy affected by resistor tolerance in the FB divider?

Output voltage accuracy directly inherits the tolerance of R1 and R2 in the FB divider network. With 0.92V ±2.8% reference, ±1% resistors contribute ±1% error; total VOUT error is root-sum-square of reference, resistor, and temperature drift terms - typically ±2.5% over temperature with 1% resistors.

Does MP2365DN-LF-P support forced PWM or discontinuous conduction mode (DCM)?

No - the MP2365DN-LF-P operates exclusively in current-mode PWM with automatic transition into pulse-skipping mode at light loads. It does not offer user-selectable DCM/PFM modes or forced PWM; light-load efficiency is maintained via reduced switching frequency rather than fixed-frequency operation.

What is the minimum recommended output capacitance for stable operation?

MPS specifies stable operation with ≥47µF ceramic output capacitance (e.g., two 22µF X5R 0805s). Lower values may cause instability or excessive ripple; ESR should be ≤10mΩ for ceramic types. Tantalum or electrolytic alternatives require ≥100µF and careful ESR selection per application note AN-107.

Can the COMP pin be left unconnected for basic operation?

No - the COMP pin must be connected to a compensation network (typically series R3–C3 to GND) to stabilize the control loop. Leaving COMP floating causes oscillation or failure to regulate; Table 3 in the datasheet provides validated R/C values for common VOUT and LC combinations.