987 Adafruit: 3.7W x2 @ 3Ω, 2.7 ~ 5.5Vin, Class D

Summary

This incredibly small stereo amplifier is surprisingly powerful - able to deliver 2 x 3.7W channels into 3 ohm impedance speakers. Inside the miniature chip is a class D controller, able to run from 2.7V-5.5VDC. Since the amp is a class D, it’s incredibly efficient (over 90% efficient when driving an 8Ω speaker at over a Watt).

This amplifier is perfect for portable and battery-powered projects. It has built in thermal and over-current protection, but you really have to drive it hard before it even gets warm! This board is a welcome upgrade to basic "LM386" amps.

Specifications

Manufacturer	Adafruit Industries LLC
Category	Audio Amplifiers
Eval Board Part Number	1528-1380-ND
Eval Board Supplier	Adafruit Industries LLC
Eval Board	Normally In Stock
Amplifier Type	Class D
Number of Outputs	Stereo
Output Power (RMS) @ Load	3.7 W x 2 @ 3 Ω
Voltage In	2.7 ~ 5.5 V
THD+N (1kHz) @ Conditions	< 0.05% @ 650 mW (4 Ω, 3.7V)
Features	Click and Pop Suppression Digital Gain Filterless Output Frequency Jitter for EMI Over Current Protection Shutdown, Enable, Standby
Efficiency @ Conditions	>85%, 5V in, 20 ~20 kHz @ 0.25 ~ 1.7 W (8 Ω ) >85%, 3.7V in, 20 ~20 kHz @ 0.2 ~ 0.9 W (8 Ω ) >80%, 5V in, 20 ~20 kHz @ 0.4 ~ 2.9 W (4 Ω ) >80%, 3.7V in, 20 ~20 kHz @ 0.2 ~ 1.55 W (4 Ω ) >75%, 5V in, 20 ~20 kHz @ 0.25 ~ 3.4 W (3 Ω ) >75%, 3.7V in, 20 ~20 kHz @ 0.2 ~ 1.8 W (3 Ω )
Standby Current [Typical]	1 µA
Quiescent Current [Typical]	2 mA
Component Count + Extras	11 + 4
Application / Target Market	Audio: MP3 Players Audio: Powered Speakers Cell Phones Portable Devices Tablets VOIP Phones
Design Author	Adafruit
Main I.C. Base Part	MAX98306
Quiescent Current [Maximum]	2.7 mA
Standby Current [Maximum]	10 µA
Date Created By Author	2013-01
Date Added To Library	2016-04