Monolithic Power Systems Inc. MP7770GF-Z

Overview

MP7770GF-Z from Monolithic Power Systems is a dual-channel Class-D audio amplifier IC capable of 2 × 45W stereo single-ended output into 4Ω or 90W mono bridge-tied-load (BTL) output into 8Ω at 36V supply, featuring integrated 100mΩ MOSFETs, programmable UVP, and analog adaptive modulation for high-fidelity audio with >90% efficiency at 10% THD.

For engineers reviewing the MP7770GF-Z datasheet, MP7770GF-Z pinout, MP7770GF-Z application, or MP7770GF-Z equivalent, key selection considerations include its TSSOP28-EP package thermal performance, dual-mode (SE/BTL) configuration flexibility, startup/shutdown pop elimination circuitry, and open-drain OTW/FAULT monitoring outputs for system-level fault handling.

Technical Context

The MP7770GF-Z implements MPS's proprietary Analog Adaptive Modulation™ (AAM™) topology, enabling variable-frequency switching up to 1MHz with fast transient response and excellent linearity without external compensation. It integrates two independent Class-D channels, each with dedicated reference (REF1/REF2), timer (TIMER1/TIMER2), and bootstrap (BST1/BST2) circuits for SE or BTL operation.

Each channel features internal 100mΩ N-channel MOSFET half-bridges, programmable under-voltage protection via UVP pin, and dual-level thermal management: OTW assertion at 125°C (hysteresis 10°C) and hard shutdown at 150°C (hysteresis 20°C). The EN input is active-high with 1.4–2.0V rising threshold and 0.4–1.0V falling threshold.

Key Specifications

Pinout & Package

TSSOP28-EP package with exposed thermal pad on bottom; 28-pin layout optimized for dual-channel Class-D layout, requiring separate AGND/PGND star grounding and localized VDD/PGND bypassing per channel.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TAS5825MRTWR and TPA3136D2PWPR, the MP7770GF-Z uniquely combines analog configurability (UVP, TIMER, REF), dual thermal flags (OTW + FAULT), and hardware-based pop elimination - making it optimal for standalone, high-reliability audio systems without MCU dependency.

Availability

MP7770GF-Z is available at Aetrix Electronics and suitable for home theater receivers, high-power soundbars, DVD/Blu-ray players, and multi-zone audio amplifiers requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP7770GF-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, with core expertise in power management and audio solutions for consumer, industrial, and automotive markets.

The MP7770 belongs to MPS's fully-integrated Class-D audio amplifier product line, designed to replace discrete power stages in space-constrained audio systems while delivering high-fidelity performance, thermal resilience, and system-level fault visibility.

FAQ

What is the minimum recommended input coupling capacitor value for MP7770GF-Z in stereo SE mode?

The minimum CIN value depends on the lowest target frequency and source impedance. For a 20Hz –3dB point with 10kΩ source impedance, CIN ≥ 0.8µF (calculated via f = 1/(2πRC)). MPS recommends ≥1µF X7R ceramic or low-ESR electrolytic capacitors placed within 5mm of IN1/IN2 pins to maintain signal integrity and minimize noise pickup.

Can MP7770GF-Z operate reliably at 36V supply with continuous 90W BTL output?

Yes, but thermal design is critical: at 36V and 90W into 8Ω, junction temperature must be maintained below 125°C to avoid OTW assertion. With θJA = 32°C/W on a 4-layer PCB, maximum ambient must be ≤65°C. Use the exposed pad soldered to ≥2cm² copper pour and add forced airflow for sustained operation.

How does the programmable UVP function prevent power-off pop?

UVP disables the amplifier when VDD falls below a user-set threshold (e.g., 8.6V for 12V systems), causing controlled shutdown before VDD droops into the unstable region where output stage bias collapses. This avoids uncontrolled DC offset transients that charge COUT and cause loud "thump" - confirmed in Figure 3 and Table 1 of the datasheet.

Is the TSSOP28-EP package lead-free and RoHS compliant?

Yes, MP7770GF-Z is fully lead-free and complies with the EU RoHS Directive 2011/65/EU. All die attach, wire bond, and finish materials meet RoHS Annex II substance restrictions, and MPS publishes full material declarations on its Quality Assurance portal.

What LC filter values are recommended for 4Ω BTL operation at 34V?

For 34V/90W BTL into 4Ω, MPS recommends 4.7µH inductors (soft-saturation ferrite core) and 2×220µF film capacitors per channel (CY1/CY2), yielding f₀ ≈ 25kHz and Q ≈ 0.85. This meets the 20kHz bandwidth requirement while suppressing >500kHz switching artifacts - validated in Figure 7 and Table 3.

Does MP7770GF-Z support I²S or other digital audio interfaces?

No, MP7770GF-Z is an analog-input Class-D amplifier only. It accepts differential analog signals at IN1/IN2 with internal VDD/2 references (REF1/REF2). Digital audio sources require external DAC + analog buffer stage; it does not decode I²S, SPDIF, or TDM signals.

How is the switching frequency adjusted for stereo SE operation to avoid beat interference?

Use different TIMER1/TIMER2 capacitor values: e.g., CINT1 = 4.7nF (700kHz) for left channel and CINT2 = 5.6nF (680kHz) for right channel at 24V. This 20kHz separation places intermodulation products outside the audio band - specified in Table 2 and verified in typical performance curves on page 10.