Gate Array - History

History

Sinclair Research ported an enhanced ZX80 design to a ULA chip for the ZX81, and later used a ULA in the ZX Spectrum. A compatible chip was made in Russia as T34VG1. Acorn Computers used several ULA chips in the BBC Micro, and later managed to compress almost all of that machine's logic into a single ULA for the Acorn Electron. Many other manufacturers from the time of the home computer boom period used ULAs in their machines. Ferranti in the UK pioneered ULA technology, then later abandoned this lead in semi-custom chips. The IBM PC took over much of the personal computer market, and the sales volumes made full-custom chips more economical.

Designers still wished for a way to create their own complex chips without the expense of full-custom design, and eventually this wish was granted with the arrival of the field-programmable gate array (FPGA), complex programmable logic device (CPLD), and Structured ASIC. Whereas a ULA required a semiconductor wafer foundry to deposit and etch the interconnections, the FPGA and CPLD had programmable interconnections.