PowerPC 400

The PowerPC 400 family is a line of 32-bit embedded RISC processor cores built using Power Architecture technology. The cores are designed to fit inside specialized applications ranging from system-on-a-chip (SoC) microcontrollers, network appliances, application-specific integrated circuits (ASICs) and field-programmable gate arrays (FPGAs) to set-top boxes, storage devices and supercomputers.

Applied Micro Circuits Corporation (AMCC) bought assets concerning the 400 family cores from IBM in April 2004 for $227 million, and they now market the processors under their own name. IBM continues evolving the cores while supplying design and foundry services around the cores. Several cores are also available for licensing by OEMs from IBM and Synopsys.

Introduced in 1994, the PowerPC 403 was one of the first PowerPC processors. It was the first one targeted strictly to the embedded market. Compared to the other PowerPC processors of the era (PowerPC 601, PowerPC 603 and PowerPC 604), it was at the very low end, lacking a memory management unit (MMU) or floating point unit (FPU), for instance. The core was offered for custom chips and in pre packaged versions, including versions with MMU, speeds ranging from 20 to 80 MHz.

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