chiplet

A chiplet is a discrete integrated circuit (die) that functions as one component within a multi-chip module. Rather than fabricating a single monolithic chip, manufacturers divide functionality across two or more smaller chiplets mounted on a common substrate or interposer. Each chiplet handles a specific subsystem, whether that is processing, memory, analog conversion, or power management. Chiplets are bonded to the substrate using solder bumps, wire bonds, or direct chiplet-to-chiplet interconnect technologies.

In power generation and grid management equipment, chiplets enable modular design of control electronics. A single module might contain a processor chiplet, a gate-driver chiplet, an analog sensor interface chiplet, and isolated communication chiplets, all communicating through high-speed interconnects on the interposer. This approach allows engineers to mix chiplets fabricated on different process nodes within one module, using older nodes for analog circuits and newer nodes for digital logic, without redesigning everything together.

The economic advantage lies in yield and cost per unit of functionality. A large monolithic chip risks total loss if a single defect appears during manufacturing. Smaller chiplets have higher yield rates individually, and a defect in one chiplet does not waste the others. For high-volume utility-grade electronics, this translates to lower scrap rates and faster time to volume production. Chiplets also allow manufacturers to use proven designs and reuse them across product families.

Challenges in chiplet integration

The main tradeoff is complexity in interconnect and testing. Chiplets must communicate through the interposer substrate, and signal integrity at these interfaces demands careful impedance control and thermal management. Substrate thickness, routing density, and the type of chiplet-to-substrate connection (micro-bumps, through-silicon vias if used, or standard solder bumps) all affect performance. Testing becomes more involved because each chiplet must be tested in isolation and then again as part of the assembled module.

The term chiplet gained currency as advanced packaging became cost-effective for high-reliability applications. In utility-scale power electronics, inverters and solid-state transformers increasingly use chiplet-based modules because the modular design accommodates thermal stress, simplifies qualification, and allows incremental technology updates. The interposer substrate itself may be organic, ceramic, or silicon, depending on the thermal and electrical requirements of the application and the operating voltage and frequency of the module.