Monolithic Power Systems Inc. MP8046DF-LF-P

Overview

MP8046DF-LF-P from Monolithic Power Systems is a 28V, 5A dual-channel power half-bridge IC configurable as full-bridge or stereo half-bridge for Class-D audio amplifiers. It integrates protected 165mΩ power switches, supports up to 600kHz switching, features 30ns dead time, and delivers 20W/channel into 4Ω at 24V in SE mode or 40W into 8Ω in BTL mode.

For engineers reviewing the MP8046DF-LF-P datasheet, MP8046DF-LF-P pinout, MP8046DF-LF-P application, or MP8046DF-LF-P equivalent, key selection considerations include channel independence, bootstrap gate drive architecture, fault flag signaling, thermal shutdown at 150°C, and compatibility with standard logic-level PWM inputs.

Technical Context

The MP8046 operates two independent high-voltage half-bridge stages, each with integrated high-side and low-side MOSFETs rated for ±5A peak current and 28V VDD. Its internal gate drivers use bootstrap supplies (BST1/BST2) with regulated VDR1/VDR2 rails, enabling efficient high-side switching without external high-side drivers.

Protection is implemented via per-channel current limiting (5A threshold), dual UVLO circuits (for VDD and gate drive rails), and die-temperature monitoring with 150°C shutdown and 130°C hysteresis. The open-drain FAULT pin asserts low on overcurrent or thermal events, with channel-specific high-impedance response.

Key Specifications

Pinout & Package

The MP8046DF-LF-P is housed in a thermally enhanced 20-pin TSSOP package with exposed pad (TSSOP20F), optimized for PCB heat dissipation and high-current routing. Pin 1 is marked by a dot; the exposed pad must be soldered to a solid ground plane for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel half-bridge driver applications.

Compared with TB6612FNG and L99H02, the MP8046DF-LF-P uniquely combines 28V operation, 5A peak current, integrated bootstrap regulation, and 600kHz capability in a single TSSOP package - making it optimal for space-constrained, high-fidelity audio and medium-power industrial motor applications where efficiency and simplicity are prioritized.

Availability

MP8046DF-LF-P is available at Aetrix Electronics and suitable for high-fidelity audio amplification, industrial motor control, DC-DC synchronous rectification, and ultrasonic transducer driving requiring stable component supply across production volumes.

Supply support for MP8046DF-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 mixed-signal ICs for power management, motion control, and audio applications.

The MP8046 belongs to MPS's high-voltage power driver product line, engineered specifically for Class-D audio amplifiers and medium-power motor control systems requiring robust protection, high efficiency, and minimal external components.

FAQ

What is the maximum recommended PCB copper area for the exposed pad of MP8046DF-LF-P?

The exposed pad must be connected to a solid ground plane covering ≥1"² of 1 oz copper to achieve the specified θJA of 40°C/W. Smaller pads increase junction temperature and risk premature thermal shutdown under sustained 5A load. Thermal vias (≥6×0.3mm diameter) should be placed directly under the pad and connected to inner-layer ground planes.

Can MP8046DF-LF-P operate with a single 24V supply for both channels?

Yes - VDD1 and VDD2 can be tied together to a common 24V rail. Each channel retains independent PWM, STBY, and fault reporting. However, separate VDD bypassing (0.1µF ceramic + 10µF tantalum per VDD pin) is mandatory to prevent coupling noise between channels during high dI/dt switching.

How does the auto-refresh bootstrap circuit affect minimum PWM duty cycle?

The internal refresh occurs every 300µs regardless of PWM duty cycle, allowing true 0%–100% modulation without external circuitry. This eliminates the minimum on-time limitation found in discrete bootstrap designs, enabling precise low-frequency and DC-coupled audio output.

Is the FAULT pin compatible with 3.3V microcontrollers?

Yes - the open-drain FAULT pin sinks current when asserted and requires only an external pull-up to 3.3V. With typical I_OL > 4mA, it reliably drives standard GPIO inputs. No level-shifter is needed, and the 1V logic threshold ensures noise margin even with long PCB traces.

What is the purpose of the dual AGND1/AGND2 pins?

AGND1 and AGND2 provide separate analog reference returns for each channel's internal logic and sensing circuitry. They must be connected to the same low-noise analog ground net - not power ground - to prevent digital switching noise from corrupting PWM threshold detection and fault flag accuracy.

Does MP8046DF-LF-P support parallel operation of both channels for higher current?

No - the device does not support paralleling OUT1 and OUT2 for single-load drive. Channels are electrically isolated with separate power grounds and gate drivers. For >5A loads, use a dedicated high-current driver or external MOSFETs with this IC as a gate controller.

What is the startup delay before OUT1/OUT2 become active after VDD application?

Each output becomes valid approximately 100µs after its respective VDD pin rises above UVLO threshold. This internal power-on reset ensures stable gate drive initialization and prevents spurious switching during supply ramp-up - critical for avoiding speaker pop or motor jerk at power-on.