Monolithic Power Systems Inc. MP7722DF-LF-Z

Overview

MP7722DF-LF-Z from Monolithic Power Systems is a stereo Class D audio amplifier IC delivering 2 × 20W into 4Ω loads at 24V, integrating dual 180mΩ MOSFET output stages, analog adaptive modulation (AAM) topology, and on-chip startup/shutdown pop elimination. It operates from a single 9.5–24V supply, achieves 0.06% THD+N at 1W/8Ω, and targets compact high-efficiency audio systems requiring low-noise, thermally robust amplification.

For engineers reviewing the MP7722DF-LF-Z datasheet, MP7722DF-LF-Z pinout, MP7722DF-LF-Z application, or MP7722DF-LF-Z equivalent, key selection criteria include its single-ended 20W/channel output architecture, integrated bootstrap circuitry for high-side drive, thermal shutdown at 150°C, mute/standby control via dual EN pins, and TSSOP20F package with exposed thermal pad.

Technical Context

The MP7722DF-LF-Z implements Monolithic Power Systems' proprietary Analog Adaptive Modulation (AAM) topology-a variable-frequency switching scheme that dynamically adjusts idle frequency (700–800 kHz typical) based on input signal and supply voltage to minimize distortion and EMI while maintaining >90% efficiency. Each channel uses independent feedback resistors and timing capacitors to set gain and quiescent switching frequency.

It employs a fully integrated dual-channel single-ended Class D output stage with internal 180mΩ N-channel MOSFETs per half-bridge, requiring external LC filters (e.g., 10µH + 0.47µF) and bootstrap capacitors (1µF between BSx and SWx). Pop elimination is achieved via controlled pre-charging of output coupling capacitors, eliminating turn-on/turn-off transients without external circuitry.

Key Specifications

Pinout & Package

MP7722DF-LF-Z is housed in a thermally enhanced 20-pin TSSOP package (TSSOP20F) with an exposed pad electrically connected to PGND for optimal heat dissipation (θJC = 6°C/W). The package supports surface-mount reflow and requires PCB land pattern per JEDEC MO-153 variation ACT.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar stereo Class D audio amplifier applications.

Compared with TAS5722LRTVR and TPA3116D2PWPR, MP7722DF-LF-Z offers superior integration for space-constrained single-ended designs-its embedded bootstrap, pop elimination, and 20W/channel capability at 93% efficiency make it optimal for TVs, monitors, and DVD players where layout area and acoustic transient suppression are critical.

Availability

MP7722DF-LF-Z is available at Aetrix Electronics and suitable for flat panel monitors, smart televisions, and multimedia computers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP7722DF-LF-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 mixed-signal ICs for power management and audio applications, with design centers across Asia and North America.

The MP7722 belongs to MPS' second-generation Class D audio amplifier product line, engineered specifically for high-efficiency, low-EMI stereo amplification in space- and thermal-constrained consumer electronics.

FAQ

What is the minimum recommended LC filter inductance for MP7722DF-LF-Z?

The datasheet specifies 10µH as the typical inductor value for the LC filter, optimized for 24V operation and 4Ω loads. Using <8µH increases output ripple and EMI; >15µH raises insertion loss and degrades high-frequency response. Toroidal or shielded gapped ferrite cores are mandatory to contain magnetic flux and meet CISPR-22 Class B emissions limits.

Can MP7722DF-LF-Z operate from a 12V supply while delivering full 20W/channel?

No-maximum output power scales with V²/R. At 12V, theoretical max into 4Ω is ~36W total (18W per channel), but practical continuous output is limited to 10W/channel due to thermal constraints and reduced headroom. The device remains functional, but efficiency drops to ~85% and THD+N rises above 0.1% above 8W/channel.

How should the exposed thermal pad on the TSSOP20F package be connected?

The exposed pad must be soldered directly to a solid copper thermal plane tied exclusively to PGND1 and PGND2. Minimum pad area is 3.2mm × 4.4mm per JEDEC MO-153; thermal vias (≥6×0.3mm diameter) should connect to inner-layer ground planes. Floating or unterminated pads cause junction temperature to exceed 150°C at <15W/channel.

Does MP7722DF-LF-Z support I²S or digital input formats?

No-it is an analog-input Class D amplifier accepting differential or single-ended line-level signals at IN1/IN2. Digital audio interfaces require external DAC (e.g., PCM5102A) with analog output buffering before connecting to MP7722DF-LF-Z inputs.

What causes audible "buzz" at 100Hz–1kHz when MP7722DF-LF-Z is enabled?

This indicates improper grounding: AGND1/AGND2 not tied at a single point to PGND1/PGND2, or SW node traces routed near IN/REF lines. The buzz is beat frequency between switching harmonics and ground-loop currents. Fix requires star-ground topology, guard traces around analog inputs, and separation of power/switching/analog zones per PCB layout guidelines.

Is the 5.0A short-circuit current limit per MOSFET or per channel?

The 5.0A limit applies independently to each MOSFET leg (high-side and low-side) within a channel. During a short, both legs of the affected channel shut down simultaneously. The protection circuit senses current in real time using on-resistance sensing-not external sense resistors-ensuring <1µs response and no false triggering under transient load peaks.

Can EN1 and EN2 be driven by separate logic signals?

No-EN1 and EN2 must be hard-wired together and driven by a single logic source. Driving them independently risks asymmetric channel enablement, causing DC offset at speaker terminals and potential damage. The datasheet explicitly states "EN1 must be connected to EN2" and provides no timing specification for staggered enable.