Microchip Adds FPGA Logic to PIC16
Author: Bryon Moyer
Microchip’s new PIC16F13145 8bit microcontroller family adds FPGA-like logic capabilities to expand the range of functions that developers can create internally. The new block may eliminate the need for an accompanying small programmable logic chip for a simpler and less expensive bill of materials.
Although the company has long employed what it calls configurable logic cells (CLCs) for building limited glue logic inside the processor, it sees increasing use of external programmable logic devices (PLDs) and small field-programmable gate arrays (FPGAs) for implementing logic beyond what the CLCs can handle. The new configurable logic block (CLB) has an FPGA structure but logic capacity like that available in a PLD, adding 32 lookup-table-based cells to the four CLCs already in place. Although the company acquired FPGA technology through its acquisition of Microsemi (and thereby Actel), the CLB technology is unrelated to those FPGAs.
If developers must employ an external PLD, the market today offers only complex versions that cost at least a couple of dollars for a similarly sized model—more than a small microcontroller costs. They also have larger packages since all 32 I/Os must have outputs in addition to pins for inputs, power, and other support signals such as clocks. Microchip’s smallest package for this MCU family has only eight pins; the largest has 20—fewer than an accompanying PLD. Placing the logic inside the MCU thus has a meaningful impact both on total cost and board size.
Available now, the 13145 sells for $0.47 in 10,000-unit quantities. The company typically withholds the process nodes it employs for its chips; it builds this unit on one of its newer nodes but declined to specify further.