Monolithic Power Systems Inc. MP7748SGF

Overview

MP7748SGF from Monolithic Power Systems is a dual-channel Class D audio amplifier IC capable of 2 × 30W stereo single-ended output into 4Ω or 60W mono bridge-tied-load (BTL) output into 8Ω, operating from a single 9.5V–36V supply, with integrated 200mΩ MOSFETs, programmable UVP, and pop-elimination circuitry - deployed in flat-panel TVs and home stereo systems.

For engineers reviewing the MP7748SGF datasheet, MP7748SGF pinout, MP7748SGF application, or MP7748SGF equivalent, key selection considerations include BTL vs. SE configuration flexibility, THD+N ≤ 0.02% at 1W/8Ω, thermal shutdown at 150°C, and TSSOP28-EP package thermal performance with exposed pad grounding.

Technical Context

The MP7748SGF implements MPS's proprietary Analog Adaptive Modulation™ (AAMTM) topology for high linearity and fast transient response without external compensation. It integrates dual independent Class D power stages, each with internal 200mΩ N-channel MOSFET half-bridges, bootstrap gate drive, and analog reference (VDD/2) generation at REF1/REF2 pins.

Each channel features dedicated enable (EN1/EN2), timer (TIMER1/TIMER2), and UVP (UVP1/UVP2) inputs enabling independent startup sequencing, programmable undervoltage shutdown thresholds (default 8.4V rising), and adjustable pop-elimination slew rate via external timing capacitors (e.g., 1μF yields ~20mA/350ms).

Key Specifications

Pinout & Package

The MP7748SGF is housed in a thermally enhanced TSSOP28-Exposed Pad package requiring solder connection of the exposed pad to PCB ground plane for θJC = 6°C/W thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TAS5825M and MAX98357A, the MP7748SGF uniquely supports both analog SE/BTL operation up to 60W, programmable UVP, and standalone analog control - making it optimal for cost-sensitive, high-fidelity, high-power consumer audio where DSP is unnecessary.

Availability

MP7748SGF is available at Aetrix Electronics and suitable for flat panel televisions, home stereo systems, and portable docking stations requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MP7748SGF 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 power management ICs, with over 20 years of leadership in DC/DC converters, LED drivers, and Class D audio amplifiers.

The MP7748SGF belongs to MPS's high-efficiency analog power amplifier product line, designed specifically for consumer audio applications demanding high output power, low distortion, and minimal external components in compact form factors.

FAQ

What is the minimum recommended input coupling capacitor value for MP7748SGF in SE configuration?

The input coupling capacitor (CIN) must set a corner frequency below the audio passband. For a 20Hz lower cutoff and typical 10kΩ input impedance, CIN ≥ 0.8μF is required. Use 1μF X7R ceramic or low-ESR film capacitors placed close to IN1/IN2 pins to minimize noise pickup and ensure stable biasing at REF1/REF2.

Can MP7748SGF operate reliably at 36V supply without derating?

Yes - the absolute maximum VDD rating is 40V, and the device is fully characterized up to 36V. At 36V, it delivers 60W into 8Ω BTL with 94% efficiency and meets all electrical specs. However, thermal design must accommodate higher power dissipation: θJA = 32°C/W requires ≥4 cm² exposed copper area and forced airflow for continuous 60W operation.

How does the programmable UVP function prevent power-down pop noise?

By setting the UVP threshold slightly below the system's brown-out voltage (e.g., 19V for a 24V rail), the MP7748SGF shuts down cleanly before VDD collapses into the unstable region where amplifier control loops misbehave. This avoids uncontrolled output transients. The default 8.4V threshold applies only when UVP pins are left open - external resistors override this to match system-level power sequencing.

Is the TSSOP28-EP package compatible with standard reflow profiles?

Yes - the MP7748SGF TSSOP28-EP package is qualified for IPC/JEDEC J-STD-020D moisture sensitivity level 3 and supports standard lead-free reflow profiles (peak 260°C). Critical for reliability: the exposed pad must be soldered to ≥4 thermal vias connected to an internal ground plane; insufficient pad soldering causes θJC degradation and thermal shutdown at <50% rated power.

What LC filter component values are recommended for 60W BTL operation at 30V?

For 60W into 8Ω BTL at 30V, use 1.5μH shielded toroidal inductors (soft saturation, ≥15A DC rating) and 2×220μF low-ESR electrolytic capacitors per channel. The LC corner frequency should be ~30kHz (Q ≈ 0.85) to pass full 20kHz audio while attenuating 600kHz switching noise by >40dB. Place LC filters within 5mm of SW1/SW2 pins with symmetric routing.

Does MP7748SGF support differential input configuration?

No - the MP7748SGF accepts single-ended analog inputs only (IN1/IN2 referenced to REF1/REF2). It does not support true differential inputs or balanced line drivers. For noise rejection in noisy environments, use shielded twisted-pair cables to IN1/IN2 with local RC filtering (e.g., 100Ω + 1nF to AGND) and ensure REF1/REF2 bypass capacitors are placed adjacent to their respective pins.

How is thermal shutdown recovery behavior implemented?

Upon reaching 150°C junction temperature, all MOSFETs disable immediately and the device enters auto-restart mode. Output remains in high-impedance state until die temperature falls below 120°C (30°C hysteresis), then it executes full soft-start sequence - including controlled output current ramp and REF voltage stabilization - to prevent pop noise during recovery.