Monolithic Power Systems Inc. MP1720DH-216-LF

Overview

MP1720DH-216-LF from Monolithic Power Systems is a mono Class-D audio amplifier in MSOP-10EP package 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, supports pin-selectable 1MHz/1.3MHz switching frequency or external clock sync, and eliminates startup/shutdown pop via 15ms controlled ramp-up.

For engineers reviewing the MP1720DH-216-LF datasheet, MP1720DH-216-LF pinout, MP1720DH-216-LF application, or MP1720DH-216-LF equivalent, key selection criteria include its filterless low-EMI operation (passes FCC radiated emissions with 24-inch unshielded cable), 53μV typical output noise at 3.3V, 0.1μA shutdown current, and thermal/short-circuit protection for portable audio power stages.

Technical Context

The MP1720DH-216-LF 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 without input capacitors when biased within range.

Switching frequency is configurable via CLK pin: grounded for 1.0MHz, floating for 1.3MHz, or driven by external TTL clock (500kHz–1.4MHz). The 21.6dB gain variant (V_BIAS = 465mV typ.) targets high-sensitivity speaker drivers requiring minimal input signal swing while maintaining SNR of 91.3dB A-weighted.

Key Specifications

Pinout & Package

MP1720DH-216-LF uses MSOP-10EP (3mm × 3mm, exposed thermal pad) package. The exposed pad must be soldered to PCB ground for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TAS5086RTJR and MAX9718AETA+, MP1720DH-216-LF uniquely combines filterless FCC compliance, external clock synchronization, and 90% efficiency-making it optimal for ultra-thin portable designs where EMI, thermal, and component count are co-constrained.

Availability

MP1720DH-216-LF is available at Aetrix Electronics and suitable for smartphone audio subsystems, wireless headphone drivers, portable media players, and IoT voice assistant speakers requiring stable component supply and long-term lifecycle support.

Supply support for MP1720DH-216-LF 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.

The MP1720 product line delivers ultra-low-EMI, filterless Class-D audio amplifiers optimized for battery-powered portable electronics where size, efficiency, and regulatory compliance are critical.

FAQ

What is the minimum recommended input coupling capacitor value for MP1720DH-216-LF with single-ended input?

For single-ended input, use ≥1μF X7R ceramic capacitor with 15kΩ input impedance to set corner frequency below 10Hz. Smaller values cause bass attenuation; tantalum or aluminum electrolytics are acceptable if voltage coefficient is low, but ceramics minimize distortion at low frequencies.

Can MP1720DH-216-LF drive an 8Ω speaker, and what output power is achievable?

Yes-it delivers 1.56W into 8Ω at 10% THD+N with 5V supply. Power drops due to lower current demand: 1.19W at 1% THD+N. For 8Ω loads, efficiency remains >85%, but thermal dissipation decreases, allowing longer continuous playback versus 4Ω operation.

How does the CLK pin function when used for external synchronization?

When CLK is driven by a TTL-compatible square wave (0.5–1.4MHz), the MP1720DH-216-LF locks its PWM carrier to that frequency. This shifts harmonic energy away from sensitive bands (e.g., GSM 900MHz receive), improving system-level EMI margin without altering gain or noise performance.

Is the thermal pad on MP1720DH-216-LF electrically connected, and how should it be routed?

Yes-the exposed pad is internally connected to PGND and must be soldered to a solid PCB ground plane. Use ≥6 thermal vias (0.3mm diameter) under the pad tied to inner-layer ground planes to achieve θ_JA = 105°C/W. Floating the pad raises junction temperature by >25°C at full load.

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

At junction temperature ≥125°C, the device disables all MOSFETs and enters latched-off state. Output pins go high-impedance. Recovery occurs automatically only after temperature falls below 112°C, with a minimum 50μs blanking period before PWM resumes-preventing oscillation near trip threshold.

Does MP1720DH-216-LF support single-ended input, and what are the trade-offs?

Yes-drive INP with signal and tie INN to mid-supply (e.g., 1.65V). However, CMRR degrades from –66dB to ~–40dB, increasing susceptibility to power rail noise. Input coupling capacitor is mandatory unless source is DC-biased within 0.2–1.9V range, limiting dynamic range in low-gain configurations.

What is the maximum allowable input signal amplitude for MP1720DH-216-LF with differential input?

With differential input and proper biasing, peak-to-peak input voltage is limited to 3.86V (calculated as 2 × (V_BIAS + 0.5V), where V_BIAS = 465mV typ.). Exceeding this risks clipping or violating absolute max ratings on INP/INN pins (–0.5V to VIN+0.3V).