Monolithic Power Systems Inc. MP6004GQ-Z

Overview

MP6004GQ-Z from Monolithic Power Systems is a primary-side regulated flyback/buck DC-DC converter with an integrated 180 V MOSFET, supporting isolated PoE (up to 13 W) and non-isolated high-voltage buck topologies. It operates in fixed peak-current, variable-frequency DCM, delivers up to 3 A programmable current limit, features 11.6 V VIN UVLO rising threshold and 5.4 V internal VCC regulation, and targets security cameras and VoIP phones.

For engineers reviewing the MP6004GQ-Z datasheet, MP6004GQ-Z pinout, MP6004GQ-Z application, or MP6004GQ-Z equivalent, key selection criteria include its dual-mode topology support (flyback with opto-coupler–free regulation and buck from up to 80 V input), thermal shutdown at 150°C, FB1 reference voltage of 1.99 V, and QFN-14 3 mm × 3 mm package compatibility with space-constrained PoE endpoints.

Technical Context

The MP6004GQ-Z implements primary-side regulation via FB1 sampling of transformer auxiliary winding voltage during secondary diode conduction, eliminating opto-couplers in flyback mode. Its DCM operation uses fixed peak current (programmable up to 3 A) and variable frequency, with 450 ns leading-edge blanking to suppress switch-node noise on the current sense path.

In buck mode, regulation relies on FB2 referenced to VIN with −1.88 V internal reference, enabling negative-referenced output configurations. MODE pin selection (GND for flyback, floating for buck) configures internal feedback routing and DCM detection logic-FB1 falling edge (50 mV) in flyback, SW-to-VIN falling edge (0.14 V) in buck-ensuring accurate zero-current switching.

Key Specifications

Pinout & Package

MP6004GQ-Z is housed in a thermally enhanced QFN-14 package (3 mm × 3 mm, 0.5 mm pitch) with exposed thermal pad. Pin 1 is located at the bottom-left corner adjacent to the marking dot; pins 4 and 12 are NC and must be floated or grounded per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side regulated flyback/buck applications.

Compared with UCC28911DR and LNK3206P, MP6004GQ-Z uniquely supports both flyback and buck topologies in one package, offers programmable current limiting for flexible magnetic design, and achieves higher power density (13 W in 3×3 mm) without sacrificing primary-side regulation accuracy or thermal robustness.

Availability

MP6004GQ-Z is available at Aetrix Electronics and suitable for security camera power supplies, VoIP phone DC-DC stages, WLAN access point bias rails, and industrial sensor node power converters requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP6004GQ-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 analog and power ICs, with over 20 years of expertise in DC-DC conversion, motor drivers, and LED lighting controllers.

The MP6004 product line was designed specifically for cost-sensitive, space-constrained PoE-powered endpoints requiring dual-mode (flyback/buck) flexibility, primary-side regulation, and integrated high-voltage switching - targeting security, communications, and industrial IoT markets.

FAQ

What is the maximum recommended input voltage for continuous operation?

The MP6004GQ-Z supports continuous operation up to 80 V input, with absolute maximum rating of 100 V on VIN. Operation above 80 V risks exceeding SOA limits under transient conditions and is not guaranteed per datasheet specifications. For 90 V surge immunity, external clamping or derating is required.

Can MP6004GQ-Z operate without an external current-sense resistor?

No. The MP6004GQ-Z uses internal current sensing but requires an external resistor from ILIM to GND to set the peak current limit. Without this resistor, the current limit defaults to minimum (≈1.2 A), risking undervoltage lockout or unstable regulation under load. A 53.6 kΩ resistor sets nominal 2.05 A limit.

How does the MODE pin affect FB1 and FB2 functionality?

When MODE is tied to GND, FB1 becomes active for flyback feedback and FB2 is internally disconnected; when MODE is floating, FB2 becomes active for buck feedback and FB1 is disabled. Incorrect MODE configuration causes feedback misrouting and output regulation failure - no auto-detection logic exists.

What is the minimum secondary diode conduction time required for reliable FB1 sampling?

The MP6004GQ-Z requires ≥3 μs of secondary diode conduction time per cycle to complete FB1 voltage sampling. If conduction time falls below this (e.g., at low VIN or heavy load), FB1 sampling fails, causing output voltage overshoot and instability. Layout and transformer design must ensure this timing margin.

Is thermal pad soldering required for functional operation?

Yes. The exposed thermal pad (pin 15) is electrically connected to GND and thermally critical. Omitting solder paste or insufficient thermal vias (>4×0.3 mm diameter) causes junction temperature to exceed 150°C at >1.5 A load, triggering thermal shutdown. IPC-7095-compliant soldering is mandatory.

Does MP6004GQ-Z support synchronous rectification?

No. The MP6004GQ-Z is designed for use with external Schottky or fast-recovery diodes in flyback mode and does not provide gate drive signals for synchronous rectifiers. Its DCM control architecture and FB1 sampling timing assume diode-based secondary-side conduction.

What is the purpose of the 450 ns leading-edge blanking window?

The 450 ns blanking window disables the current sense comparator immediately after SW turn-on to ignore parasitic ringing from transformer leakage inductance and MOSFET capacitance. This prevents false current-limit triggering and ensures accurate peak current detection during the linear ramp phase.