Monolithic Power Systems Inc. MP1720DH-3-LF-P

Overview

MP1720DH-3-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 pin-selectable 1MHz/1.3MHz switching frequency, 90% efficiency, and integrated 250mΩ MOSFETs. It operates in fully differential mode, supports pop-free startup/shutdown, and eliminates external LC filters by passing FCC radiated emissions with 24-inch unshielded cable - deployed in portable audio systems requiring compact, low-EMI amplification.

For engineers reviewing the MP1720DH-3-LF-P datasheet, MP1720DH-3-LF-P pinout, MP1720DH-3-LF-P application, or MP1720DH-3-LF-P equivalent, key selection criteria include fixed 3dB gain setting, MSOP-10EP thermal-pad package, differential input bias voltage (950–1035 mV), 15ms startup time, and shutdown current of 0.1μA - all critical for battery-powered handheld audio design.

Technical Context

The MP1720DH-3-LF-P implements a BTL (bridge-tied load) Class-D architecture with fully differential inputs and outputs, using internal sawtooth-based PWM modulation synchronized to either internal 1.0MHz/1.3MHz clocks or an external TTL clock (500kHz–1.4MHz). Its output stage integrates matched high-side/low-side power MOSFETs with 250mΩ R_DS(on) at 3.3V.

It features analog input biasing (950–1035 mV for -3 variant), programmable gain via part number (3dB = 1.4× V/V), and dual protection: thermal shutdown activating at +125°C with hysteresis (resumes at +112°C) and cycle-by-cycle short-circuit detection disabling both MOSFETs for ≥50μs after fault clearance.

Key Specifications

Pinout & Package

MP1720DH-3-LF-P is housed in a thermally enhanced MSOP-10EP (3mm × 4.9mm) package with exposed thermal pad (Pin 10) requiring PCB ground connection for thermal management and EMI control.

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 MAX9718DETE+T, MP1720DH-3-LF-P uniquely combines fixed 3dB gain, differential input, filterless FCC compliance, and MSOP-10EP thermal performance - making it optimal for space-constrained, noise-immune mono audio in battery-powered handhelds.

Availability

MP1720DH-3-LF-P is available at Aetrix Electronics and suitable for smartphone audio subsystems, wireless headset drivers, portable media player output stages, and IoT voice assistant speakers requiring stable component supply, consistent parametric performance, and RoHS-compliant packaging.

Supply support for MP1720DH-3-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 core expertise in DC/DC conversion, LED drivers, motor drivers, and Class-D audio amplifiers.

The MP1720 product line targets portable audio applications demanding high efficiency, low EMI, and minimal external components - specifically engineered for smartphones, wearables, and battery-powered consumer electronics.

FAQ

What is the recommended input configuration for MP1720DH-3-LF-P in noisy environments?

For noisy environments such as smartphone PCBs with co-located RF transceivers, the MP1720DH-3-LF-P must be used with fully differential input - leveraging its 66dB CMRR and internal biasing (950–1035 mV) to reject common-mode noise without coupling capacitors. Single-ended use requires input AC-coupling and sacrifices noise immunity.

Does MP1720DH-3-LF-P require an external LC filter to meet FCC radiated emissions?

No. MP1720DH-3-LF-P passes FCC radiated emissions standards with up to 24 inches of unshielded twisted-pair speaker cable and no external LC filter, due to its integrated EMI-reduction scheme and selectable 1.0/1.3MHz switching frequency - confirmed per MPS Rev. 1.02 datasheet Figure 1 and Application Note AN-107.

How does the thermal pad (Pin 10) affect performance and reliability?

The exposed thermal pad (PVIN) must be soldered to a solid PCB ground plane to achieve θ_JA = 105°C/W and prevent thermal shutdown. Without proper grounding, junction temperature rises rapidly under 2.7W load, triggering thermal protection at +125°C and degrading long-term reliability - per Absolute Maximum Ratings table.

Can MP1720DH-3-LF-P be synchronized to an external clock, and what is the valid frequency range?

Yes. Driving the CLK pin with a TTL-compatible external clock synchronizes switching to that source. Valid frequency range is 500kHz to 1.4MHz - verified in Electrical Characteristics table (FCLK Min/Max = 500/1400 kHz) and Operation section - enabling harmonic placement outside sensitive RF bands like 2.4GHz.

What is the maximum output power into 8Ω, and how does it compare to 4Ω operation?

At 10% THD+N and 5V supply, MP1720DH-3-LF-P delivers 1.56W into 8Ω - 44% less than its 2.78W into 4Ω. This reflects the square-law relationship between load impedance and power in BTL topology; efficiency remains >85% across both loads per Operation Characteristics table.

Is MP1720DH-3-LF-P compatible with single-cell lithium-ion battery operation?

Yes. Its 2.5V to 5.5V input range covers full discharge-to-charge profile of single-cell Li-ion (2.8V–4.2V nominal), and quiescent current of 4mA @ 3.3V plus 0.1μA shutdown current ensures >300-hour standby in always-listening voice devices - validated in Recommended Operating Conditions and Electrical Characteristics tables.