MAX9788ETI[2]

Updated: 2026-09-16

Overview

The MAX9788ETI is a stereo Class D audio amplifier developed by Maxim Integrated (now part of Analog Devices). It is designed for portable audio applications, offering high efficiency and low power consumption. The amplifier operates in Class D mode, which significantly reduces heat generation compared to traditional Class AB amplifiers, making it suitable for compact, battery-powered devices. The MAX9788ETI features a small footprint and minimal external components, simplifying integration into space-constrained designs. It supports a wide supply voltage range and includes built-in protection features such as thermal shutdown and short-circuit protection, enhancing reliability in real-world applications.

Structure and Working Principle

The MAX9788ETI integrates two Class D amplifier channels, each capable of delivering high-quality audio output with low distortion. The amplifier uses pulse-width modulation (PWM) to convert analog audio signals into digital pulses, which are then filtered to reconstruct the audio signal at the output. This method ensures high efficiency, typically above 90%, reducing power consumption and extending battery life. The device includes an internal oscillator and requires only a few external components, such as inductors and capacitors, to form a complete audio amplifier circuit. Its differential inputs help reject common-mode noise, improving audio fidelity in noisy environments.

Key Features

The MAX9788ETI stands out for its ultra-low power consumption, making it ideal for battery-operated devices. It offers a signal-to-noise ratio (SNR) of over 90 dB, ensuring clear and crisp audio playback. The amplifier also features a shutdown mode that reduces current draw to less than 1 µA when not in use. Other notable features include a wide supply voltage range (2.5V to 5.5V), which accommodates various power sources, and a compact 28-pin TQFN package that saves board space. The device is also RoHS compliant, meeting environmental regulations for lead-free manufacturing.

Application Areas

The MAX9788ETI is widely used in portable audio devices, including smartphones, tablets, Bluetooth speakers, and handheld gaming consoles. Its high efficiency and small size make it a preferred choice for designers looking to optimize both performance and space. Beyond consumer electronics, the amplifier is also employed in medical devices, such as portable ultrasound machines, where reliable and efficient audio output is critical. Its low power consumption and robust performance under varying conditions make it suitable for industrial applications as well.

Maintenance and Precautions

To ensure optimal performance, the MAX9788ETI should be used with a properly designed PCB layout that minimizes parasitic inductance and capacitance. Thermal vias and adequate copper area are recommended to dissipate heat effectively. Avoid exceeding the maximum supply voltage (5.5V) to prevent damage to the device. Follow the manufacturer's guidelines for input signal levels and output load conditions. Regular testing under real-world operating conditions is advised to validate long-term reliability.

B2B Procurement Guide

When sourcing the MAX9788ETI, prioritize authorized distributors to ensure genuine components and reliable supply chains. Bulk purchases typically offer cost savings, but verify minimum order quantities (MOQs) and lead times. Evaluate suppliers based on technical support, including access to datasheets, application notes, and design tools. Consider alternative part numbers or equivalent solutions if availability is constrained. Negotiate pricing based on volume commitments and long-term partnerships.