ESS Technologies Introduces Smart Power-Amplifier with Voltage-Tripling Boost and Multi-Level Class-D

< Newsroom | Posted: Tuesday November 5, 2019

ESS Smart Power-Amplifier with revolutionary new amplifier design provides boosted audio power with speaker protection in the smallest solution available

Milpitas, California – ESS Technology, the industry leader in audio converters and analog design, announces the ES8018 SABRE® Smart Power-Amplifier (SPA).  Designed to boost the audio quality and efficiency of phones, tablet, wireless speakers, and watches. The ES8018 combines major advances in amplifier design with advanced speaker-protection algorithms.  It is based on patented 7-level Class-D amplifier technology offering improved efficiency and lower EMI than standard amplifiers.  The product uses a voltage-tripling capacitive boost that generates up to three times the battery supply without the use of a bulky and expensive inductor.  These advances are coupled with the legendary sound quality of SABRE DACs, and advanced audio processing algorithms from the audio experts at ESS.  As a result of this combination system makers can get amazing audio quality from micro speakers while having a small and cost-effective solution.

The ES8018 is a self-contained Smart-Amplifier with integrated DSP that runs a cutting-edge speaker-protection and signal-boost algorithm.  The ES8018 has fully proven temperature and excursion protection that adapts to the changes in real time. It is capable of safely delivering 4.5 watts into an 8ohm speaker, and can be used to drive both micro speakers and receivers in a dedicated low-noise mode.

Inductorless, voltage-tripling, capacitive boost

The ES8018 uses a unique voltage-tripling boost, the solution is based on using the combination of a voltage-doubler and voltage-mirror circuit.  This voltage-tripling results in an effective boost-voltage of 13V from a typical phone battery, and can reach 15V from a 5V supply.   Both the high and low-side boost are accomplished using captive techniques, eliminating the need for a large and expensive inductor, replacing it with two low-cost and small capacitors, resulting in a solution that requires 40% less board space and has a significantly lower profile.  The advanced analog-control loop in the amplifier automatically corrects for any loss of power due to battery discharge preventing impacts to audio quality while simultaneously preventing brown-out due to large currents.

Seven-Point Multi-Level Class-D amplifier topology

The Patented Multi-Level Class-D(MLCD) amplifier in the ES8018 tracks the amplitude of the audio signal and seamlessly switches between seven different switching-patterns on the output.  The output effectively floats along with the signal. The result is an amplifier that can deliver peak-output swings of 15V while only ever switching 5V.  This gives improvements in efficiency and lowers EMI radiation.  Unlike competing amplifiers that rely on a fixed boost circuit, the ES8018 never switch the full 15 volts, avoiding significant EMI and efficiency-loss.  This is critical for real-world audio signals with large crest factors.  The digital control loop, used in the competitors inductive-boosts, requires a look-ahead approach to charge the converter and wastes power when idle or turned-off, the ES8018’s analog control loop has none of these penalties, providing peak-power instantaneously.

Switching Patterns for an increasing sign wave showing 7 levels at full scale.

According to Shawn Scarlett, Marketing Director for ESS, “The ES8018 has several distinct advantages over Inductive-boost solutions; By removing the inductor we can make the end systems smaller , while delivering amazing sound quality”  he continued “We have effectively created a new amplifier class that offers incredible sound and efficiency, opening the way for whole new  level of performance and experience”

The new ES8018 is ideal for smartphones, smart-watches, and any device with tight space constraints on the speaker.  The amplifier is available with a full application suite to enable effective speaker modeling and sound-quality tuning.  The ES8018 is in production now with samples and evaluation boards are available.  For more information contact your local ESS representative.


About ESS Technology
For more than three decades, ESS Technology has been on the cutting edge of audio technology. A privately-held fabless semiconductor company, ESS Technology designs and markets high-performance analog and HiFi audio devices for mobile, consumer, automotive, and professional audiophile systems. The company was founded in 1984, and today ESS Technology is best known for its SABRE series of high-performance audio products. For more information, visit