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

Overview

MP1720DQ-216-LF-P from Monolithic Power Systems is a mono Class-D audio amplifier delivering 2.7W into 4Ω at 10% THD+N with 5V supply, featuring 21.6dB fixed gain, 90% efficiency, and integrated 250mΩ MOSFETs. It operates in BTL mode with fully differential inputs, eliminates startup/shutdown pop via 15ms controlled ramp, and targets portable audio systems requiring low-EMI operation without output LC filters.

For engineers reviewing the MP1720DQ-216-LF-P datasheet, MP1720DQ-216-LF-P pinout, MP1720DQ-216-LF-P application, or MP1720DQ-216-LF-P equivalent, key selection criteria include its 21.6dB gain setting, 1.0/1.3MHz switchable frequency, 53μV typical input-referred noise at 3.3V, thermal/short-circuit protection, and QFN10 package compatibility with high-density PCB layouts.

Technical Context

The MP1720DQ-216-LF-P implements a pulse-width modulation (PWM) Class-D architecture with a full-bridge BTL output stage and internal sawtooth oscillator. Its differential input stage accepts common-mode voltages from 0.2V to 1.9V, enabling direct coupling from biased sources while rejecting noise.

Switching frequency is configurable via the CLK pin: grounded for 1.0MHz, floating for 1.3MHz, or driven by an external TTL clock (500kHz–1.4MHz). This flexibility avoids interference with sensitive RF bands and enables EMI compliance-passing FCC radiated emissions with 24-inch unshielded cable and no output filter.

Key Specifications

Pinout & Package

MP1720DQ-216-LF-P uses a 3mm × 3mm, 10-pin QFN package with exposed thermal pad (Pin 10) requiring solder connection to PCB ground for thermal management and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TAS5342AIDBTR and MAX9718ETA+, MP1720DQ-216-LF-P uniquely combines filterless FCC compliance, 21.6dB gain, and 90% efficiency in a 3×3mm QFN - making it optimal for EMI-sensitive, battery-limited portable audio where gain matching and thermal performance are critical.

Availability

MP1720DQ-216-LF-P is available at Aetrix Electronics and suitable for smartphone audio subsystems, wireless headset drivers, portable media player output stages, and IoT voice interface speaker applications requiring stable component supply and long-term production continuity.

Supply support for MP1720DQ-216-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 power ICs, with expertise in DC/DC conversion, motor drivers, and audio amplifiers for portable and industrial markets.

The MP1720 product line delivers highly integrated, filterless Class-D audio amplifiers targeting space- and power-constrained portable electronics - designed to replace legacy AB amplifiers while achieving >90% efficiency and FCC-compliant EMI performance.

FAQ

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

The exposed thermal pad (Pin 10, labeled PVIN) serves dual functions: it connects internally to the power MOSFET sources for low-impedance current return and acts as the primary thermal path. It must be soldered to a large PCB copper pour tied to system ground to maintain junction temperature below +125°C under 2.7W load and ensure reliable thermal shutdown operation.

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

Yes - MP1720DQ-216-LF-P supports single-ended input via AC coupling using a 15kΩ input resistor and external capacitor. However, differential input is strongly recommended for noise immunity; single-ended use requires careful layout to avoid ground loop noise and limits maximum input swing due to -0.5V absolute minimum pin voltage rating.

How does the 21.6dB gain option differ from other MP1720 variants?

The MP1720DQ-216-LF-P's 21.6dB gain (12.0× voltage gain) is the highest among MP1720 variants, enabling direct interface with low-output-voltage DACs or high-impedance line sources without external pre-amplification. It achieves this via internal resistor network setting VBIAS to 465mV (typical), allowing up to 3.86VPP differential input before clipping at 5V supply.

Does MP1720DQ-216-LF-P require an output LC filter to meet EMI standards?

No - MP1720DQ-216-LF-P passes FCC radiated emissions with 24-inch unshielded twisted-pair speaker cable and no external LC filter, thanks to its spread-spectrum-capable 1.0/1.3MHz switching frequency and integrated EMI-reduction architecture. External filtering is optional only for extreme EMI environments or non-standard cable configurations.

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

When junction temperature exceeds +125°C, MP1720DQ-216-LF-P disables all MOSFETs and enters thermal shutdown. Outputs go to high-impedance, and the device remains disabled for ≥50μs. Normal operation resumes only after junction temperature falls below +112°C - verified by internal thermal sensor - ensuring safe cooldown before re-enabling switching.

Is the SHDN pin active-high or active-low, and what is its leakage behavior?

The SHDN pin is active-high: driving it above 1.6V (min) enables the amplifier; pulling it below 0.45V (max) forces shutdown. Input leakage is ±1μA at 6.3V, allowing direct connection to GPIOs without external pull resistors. In shutdown, total current drops to 0.1μA (typ), making it suitable for battery-backed systems requiring nanowatt standby.

How does the CLK pin affect EMI performance in real-world layouts?

Setting CLK to GND (1.0MHz) or FLOAT (1.3MHz) shifts fundamental switching harmonics away from sensitive bands like GSM 900MHz or Bluetooth 2.4GHz. Using an external clock synchronized to system timing further randomizes spectral energy, reducing peak emissions by up to 10dB - validated in MP1720 evaluation boards with 2-layer PCBs and standard FR4.