Monolithic Power Systems Inc. MP1567DK-LF-P

Overview

MP1567DK-LF-P from Monolithic Power Systems is a 1.2A, 800kHz synchronous step-down DC/DC converter in a 10-pin MSOP package, designed for space-constrained low-voltage systems. It operates from 2.6V to 6V input, delivers regulated output down to 0.9V (e.g., 1.8V @ 1.2A), achieves >90% efficiency via integrated 180mΩ high-side and 220mΩ low-side MOSFETs, and includes soft-start, cycle-by-cycle current limiting, UVLO, and thermal shutdown - enabling compact power rails in handheld and portable electronics.

For engineers reviewing the MP1567DK-LF-P datasheet, MP1567DK-LF-P pinout, MP1567DK-LF-P application, or MP1567DK-LF-P equivalent, key selection criteria include its 800kHz fixed-frequency operation, internal power switches, 0.9V feedback reference, zero-current shutdown mode, and compatibility with ceramic output capacitors in SOHO routers, PDAs, and digital video cameras.

Technical Context

The MP1567DK-LF-P implements current-mode control with an internal 0.9V reference and transconductance error amplifier (G_EA = 300 µA/V, A_VEA = 400 V/V), enabling stable regulation under dynamic load conditions. Its 800kHz oscillator sets switching frequency independently of input/output voltage, supporting small external LC filters.

It integrates dual N-channel MOSFETs (180mΩ HS / 220mΩ LS) with bootstrap gate drive (BS pin), requiring only a 10nF capacitor between BS and SW. Protection features include under-voltage lockout (2.2V threshold, 100mV hysteresis), thermal shutdown at 160°C, and source/sink current limiting (2.0A source, 350mA sink).

Key Specifications

Pinout & Package

MP1567DK-LF-P uses a thermally enhanced 10-pin MSOP package (3mm × 4.9mm, 0.5mm pitch) with exposed pad for PGND connection and θ_JA = 150°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP1567DK-LF-P, MP2101DJ-LF-Z trades current capacity for higher frequency and smaller magnetics, while TPS62231DRYR offers greater output current and integration at the cost of layout flexibility and bootstrap-driven gate drive.

Availability

MP1567DK-LF-P is available at Aetrix Electronics and suitable for SOHO routers, handheld computers, and digital video cameras requiring stable component supply, long-term manufacturability, and RoHS-compliant packaging.

Supply support for MP1567DK-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 Kirkland, WA, with design centers worldwide.

The MP1567 belongs to MPS's mainstream DC/DC converter product line targeting portable and space-constrained applications, emphasizing integration, thermal efficiency, and ease of layout for battery-powered consumer electronics.

FAQ

What is the maximum recommended output voltage for MP1567DK-LF-P?

The MP1567DK-LF-P supports output voltages up to 4.5V, as specified in its Recommended Operating Conditions. This is achieved using the external resistive feedback divider with the 0.905V internal reference; for example, a 1.2MΩ top resistor and 240kΩ bottom resistor yields 4.5V output. Exceeding 4.5V risks violating internal voltage limits on the COMP and FB pins.

Can MP1567DK-LF-P operate with a 2.5V input supply?

No - the absolute minimum input voltage is 2.6V per the Absolute Maximum Ratings table, and the undervoltage lockout activates below 2.2V. At 2.5V, the device will not start or may latch off unpredictably. For true 2.5V operation, consider the MP2101 series or MPQ4420A, which specify 2.5V minimum input.

Is an external bootstrap diode required for MP1567DK-LF-P?

An external bootstrap diode (e.g., IN4148) is optional and only recommended when V_OUT ≥ 3.3V and duty cycle exceeds 65% (i.e., V_OUT/V_IN > 0.65). It improves high-duty-cycle efficiency by supplementing the internal bootstrap charge path; it is unnecessary for 1.8V outputs from 5V input.

What is the thermal performance difference between MSOP-10 and QFN-10 packages?

The MSOP-10 package has θ_JA = 150°C/W, while the QFN-10 (3mm × 3mm) achieves θ_JA = 50°C/W due to its exposed thermal pad. Under identical 1.2A load and PCB layout, the QFN version runs ~100°C cooler - making it preferred for thermally dense applications like digital video cameras where ambient temperature exceeds 60°C.

How does the MP1567DK-LF-P handle output short-circuit conditions?

Under output short, the MP1567DK-LF-P enters hiccup mode: it cycles between brief on-pulses (limited by 2.0A source current) and shutdown intervals, drawing <1µA average current. This protects internal MOSFETs and prevents thermal runaway, unlike latch-off or constant-current foldback schemes used in some competitors.

Does MP1567DK-LF-P support adjustable switching frequency?

No - the MP1567DK-LF-P has a fixed 800kHz internal oscillator. Frequency cannot be adjusted via external components or pin strapping. For variable-frequency operation, consider the MP2307 (500kHz–1.5MHz) or MPQ4420A (300kHz–2.2MHz), both of which offer SYNC pin capability.

What is the minimum output capacitor ESR requirement for stability?

The MP1567DK-LF-P is optimized for low-ESR ceramic capacitors and does not require a minimum ESR for loop stability. In fact, high-ESR tantalum or electrolytic capacitors introduce a zero that may destabilize the control loop unless compensated with C4. The datasheet recommends 10µF X5R/X7R ceramics as standard for all output voltages.