The semiconductor industry is often described in terms of ‘gaps’ between two or more parametrics. With the rapidly increasing mobile device market, we have a new gap to worry about – the Battery Gap for mobile devices.
A classic example of a semiconductor design gap is the so-called Design Productivity Gap, which describes how many logic transistors can be designed on a chip vs. how many transistors are available for design on that chip at a specific foundry process node. Another example is the Verification Gap – the difference between how many transistors can be designed into an SoC and how many can be adequately verified for that particular design. Both the Design Productivity and Verification Gaps share a common element – both are widening over time as semiconductor technology advances, which means that the effort needed to design complex SoCs increases drastically as process nodes shrink.
As process nodes advance with smaller feature sizes, in general the power dissipated by a transistor decreases. However, this is more than offset by the placement of more transistors on a chip with each node advancement. Various circuit and system design techniques are very effective in bringing down both standby and active SoC power. In addition, there are specialty IP core available that help extend battery life (at the cost of additional silicon area), but the usefulness of a mobile device is still often limited by its battery before recharging or a new battery is needed. This is where the Battery Gap is found – battery technology, as measured by energy storage per unit volume, is not keeping up with semiconductor process and design advancements for increasing battery life.
Bigger batteries are only a stopgap and a limited solution and they add weight and volume to a device. The electronics industry needs to put more emphasis on battery technology to help support the expanding growth of portable communication and other devices, particularly for the consumer market.
I’m interested in hearing how you think this can be accomplished.