A 76 MHz programmable logic sequencer

Abstract

The authors describe a BiCMOS programmable logic sequencer which provides reduced power, has functional density and flexibility similar to that of CMOS, and maintains speed as high as that of bipolar devices. The device is organized as 16 inputs, 48 product terms, and 8 registered outputs. Both logic AND and OR arrays are designed for user-programmability, enabling any chosen product term to be shared as a common sum-of-products by all of the outputs without resorting to a large number of product terms. A separate BiCMOS programming path test chip, compatible with this device, was manufactured simultaneously and evaluated separately. The equivalent gate count for this device is approximately 1000 gates. A maximum operating frequency of 76 Mhz, with 6-ns clock to output delay and 7-ns input setup time at a power dissipation of 370 mW, has been achieved. The process used to fabricate this device is a merged bipolar and CMOS technology featuring 1.9- mu m L/sub eff/ and 1.2- mu m*3- mu m emitter, three-layer metal and single-layer polycide for interconnections, TiW fuses, PtSi Schottky diodes, and polysilicon resistors.<>