Monolithic Power Systems Inc. MP1720DQ-216-LF-Z

Overview

MP1720DQ-216-LF-Z from Monolithic Power Systems is a mono Class-D audio amplifier delivering 2.7W into 4Ω at 5V with 10% THD+N, featuring 21.6dB fixed gain, 90% peak efficiency, and integrated 250mΩ MOSFETs. It operates in QFN10 (3mm × 3mm) package with thermal pad, targets space-constrained portable audio systems requiring low-EMI operation without output LC filters.

For engineers reviewing the MP1720DQ-216-LF-Z datasheet, MP1720DQ-216-LF-Z pinout, MP1720DQ-216-LF-Z application, or MP1720DQ-216-LF-Z equivalent, key selection criteria include fixed 21.6dB gain configuration, 1.0/1.3MHz switchable frequency, differential input support, pop-free 15ms startup, and FCC-radiated emissions compliance with 24-inch unshielded cable.

Technical Context

The MP1720DQ-216-LF-Z implements a fully differential BTL (bridge-tied load) Class-D architecture with internal PWM modulation driven by a sawtooth oscillator and comparator-based signal processing. Its gain is factory-set to 21.6dB (12.0× voltage gain), enabling high-sensitivity single-ended or differential input drive while maintaining ±80mV output offset and 91.3dB A-weighted SNR.

Switching frequency is selectable via CLK pin: grounded for 1.0MHz, floating for 1.3MHz, or externally synchronized between 500kHz–1.4MHz. Internal thermal shutdown triggers at +125°C and recovers at +112°C; short-circuit protection disables both high-side and low-side MOSFETs upon current threshold exceedance.

Key Specifications

Pinout & Package

MP1720DQ-216-LF-Z is housed in a thermally enhanced 10-pin QFN package (3mm × 3mm, 0.5mm pitch) with exposed thermal pad (Pin 10) that must be soldered to PCB ground for thermal management and electrical stability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TAS5706BRTJR and TPA2013D1YZFT, MP1720DQ-216-LF-Z offers superior EMI performance without LC filtering, tighter THD+N (0.13%), and true differential input for noise immunity - making it optimal for space-constrained, battery-powered audio endpoints where layout simplicity and acoustic quality are prioritized over digital configurability.

Availability

MP1720DQ-216-LF-Z is available at Aetrix Electronics and suitable for smartphone audio amplification, wireless headphone transmitters, portable media players, and IoT voice assistant speakers requiring stable component supply and RoHS-compliant packaging.

Supply support for MP1720DQ-216-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 power ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MP1720 product line delivers highly integrated, low-EMI Class-D audio amplifiers targeting portable consumer electronics where efficiency, small footprint, and regulatory compliance are critical design constraints.

FAQ

What is the purpose of the thermal pad (Pin 10) on MP1720DQ-216-LF-Z?

Pin 10 is the exposed thermal pad connected internally to PVIN and must be soldered to a large PCB copper pour tied to ground. This achieves θJA = 50°C/W, enabling safe 2.7W operation at +85°C ambient. Omitting thermal pad connection risks thermal shutdown above 1.2W continuous output.

Can MP1720DQ-216-LF-Z operate with a single-ended input?

Yes - INN can be AC-coupled to mid-supply (e.g., 1.65V) while INP accepts the signal. However, differential input is strongly recommended for noise immunity. With single-ended use, input coupling capacitors are mandatory, and maximum input swing is reduced due to VBIAS limitations (410–530mV for MP1720-216).

How does the 21.6dB gain option affect system-level signal chain design?

The 21.6dB (12×) gain allows direct interfacing with low-output-voltage DACs or codecs (e.g., 210mV RMS full-scale), eliminating need for pre-amplification. It also increases sensitivity to input noise - hence differential input and proper PCB layout (separated analog/digital grounds) are essential to maintain 91.3dB SNR.

Does MP1720DQ-216-LF-Z require an external clock to meet FCC emissions?

No - the device passes FCC radiated emissions with 24-inch unshielded cable using its internal 1.0MHz or 1.3MHz oscillator. External clock synchronization (500kHz–1.4MHz) is optional and used only to shift switching harmonics away from sensitive RF bands (e.g., Bluetooth 2.4GHz or cellular LTE bands).

What happens during thermal shutdown, and how does recovery work?

When junction temperature exceeds +125°C, the amplifier disables all MOSFETs and enters thermal shutdown. Output goes high-impedance, and device remains latched off for ≥50μs. Normal operation resumes only after junction temperature falls below +112°C - hysteresis prevents cycling near trip point.

Is the 2.7W output rating achievable at 3.3V supply?

At 3.3V, MP1720DQ-216-LF-Z delivers 1.18W into 4Ω at 10% THD+N (per datasheet Table on p.4). The 2.7W rating is specified at 5.0V. Lower supply reduces headroom and maximum undistorted output - design margin must account for battery voltage sag during peak load.

Why does MP1720DQ-216-LF-Z specify different input bias voltages across gain variants?

VBIAS is trimmed per gain version to optimize common-mode input range and minimize THD+N. For MP1720-216, VBIAS = 465mV (typ.) sets the input DC operating point to maximize signal swing before clipping, especially critical given its high gain and narrow allowable input voltage window (±0.5V relative to VBIAS).