Low power spiking AI-Arm edge processing from voltage scaling on ETA TENSAI chip

Read an article in IEEE Spectrum (ETA Compute debuts spiking NN chip for edge AI) about a company producing a new AI IOT chip based on ARM microprocessors with DSPs for dedicated matrix computations.

The new ETA Compute TENSAI chip  technology supports spiking neural networks (NN) as well as more normal, convolutional NN  depending on  edge AI requirements. More  information can be found in an Embedded Computing article (Micropower intelligence for edge devices) and a EE News article (ETA adds spiking NN support to MCU)

We have discussed spiking NN  in prior posts  latest post: IBM using PCM for better AI -round 6). Any spiking NN more closely mimics real biological neurons present in the brains of humans and other life.

ETA also claims that spiking NN perform better unsupervised learning. They included some examples of this in videos. In one video, ETA trains a spiking NN to do the same job as a convolutional NN with 1/10th the pixel data.

In addition, spiking NN only use neural weight values of 0 or 1, whereas normal convolutional NN operations require 8 to 16 bit numbers. So spiking NN arithmetic really only uses addition while convolutional NN need 8-16 bit multiplicative arithmetic to determine resultant weights.

Voltage scaling saves power

The other claim is that the TENSAI chip can perform computations on the order of 10 microwatts of power per megahertz (~10 μW/MHz) using the ARM/DSP combination with voltage scaling

The new TENSAI chip is their 3rd generation with multiple ARM M3 cores and NXP digital signal processors. These cores are implemented in a sub-threshold, asynchronous mode process that allows them to operate at much lower voltage, ~0.2V and at varying clock frequencies. This is called voltage scaling electronics. Doing this took analog design, which ETA considers part of their special IP.

ETA claims the TENSAI chip can operate in listen mode (“Ok Google?”) and only consume 50 microwatts of power and once a key word is discovered, operate in full computational mode with 500 microwatts of power.

I couldn’t find a data sheet for the TENSAI chip, so was unable to see how many TOPS/W it could perform as discussed in prior posts (see: AI processing at the edge post). But it looks to be even more power efficient.

The TENSAI chip was announced at ARM Tech Con(terence) and won the Design Innovation of the Year award at the conference.


Photo Credits: Photo and caption from Figure 12 in  A brain inspired architecture…,  AIP Journal of Applied Physics article

Photo from EE News ETA adds spiking NN support to MCU article

Chart from Embedded Computing  Micropower intelligence for edge devices article

Board photo from IEEE Spectrum ETA Compute debuts spiking NN chip for edge AI article