Boosted 2.2W Class D Amplifier with Automatic Level Control

High-Efficiency Boosted Amplifier Makes Speakers Louder Without Collapsing the Battery


The MAX98500 is a high-efficiency Class D audio amplifier that features an integrated boost converter, to deliver a constant output power over a wide range of battery supply voltages.

The boost converter operates at 2MHz, requiring only a small (2.2µH) external inductor and capacitor.

The automatic level control has a battery tracking function that reduces the output swing as the supply voltage drops, preventing collapse of battery voltage.

The amplifier has differential inputs and an internal fully differential design. The MAX98500 also features three gain settings (6dB, 15.5dB, and 20dB) that are selectable with a logic input.

The MAX98500 is available in a small, 0.5mm pitch 16-bump WLP package (2.1mm x 2.1mm). It is specified over the extended -40°C to +85°C temperature range.
MAX98500: Simplified Block Diagram MAX98500: Simplified Block Diagram Enlarge+

Key Features

  • Boosted Class D Output
  • Integrated Automatic Level Control
  • Output Power
    • 2.2W into 8Ω, 10% THD+N
    • 1.7W into 8Ω, 1% THD+N
  • Wide 2.5V to 5.5V Supply Voltage Range
  • Undervoltage Lockout Protection
  • High Total Efficiency of 87%
  • High Step-Up Switching Frequency (2MHz)
  • Active Emission Limiting for Low EMI


  • Active Speaker Accessories
  • Cell Phones
  • GPS Devices
  • Mobile Internet Devices
  • Smartphones
Part Number Class Spkr. Amp. VCC
Spkr. Amp. VCC
Spkr. Amp. ICC
POUT into 8Ω @ 1% THD+N
POUT into 8Ω @ 10% THD+N
Spkr. Amp. Half Pwr. THD+N
Package/Pins Budgetary
min max typ min min min See Notes
MAX98500  Boosted/D 2.5 5.5 3.05 1.7 2.2 0.05 95
$0.72 @1k
See All Speaker Amplifiers (33)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX98500EVKIT: Evaluation Kit for the MAX98500

Technical Documents

App Note 5792 Multiplex Boosted Class-D without Additional External Circuitry

Quality and Environmental Data

Product Reliability Reports: MAX98500.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Related Resources