A normally-off process for analogue/digital GaAs ASICs

An enhancement mode process developed by Philips Research Labs is available through foundry service at Philips Microwave Limeil. This process is meant to address not only purely digital circuits, but also low-cost, ultra low power analogue and analogue-digital mixed functions with high integration density. In this article, an integrated GPS front-end, designed and fabricated by PNL/LEP, is described. This 3-chip receiver includes an integrated VCO, amplifiers, a mixer, a phase frequency comparator, a 2-bit ADC, registers and several prescalers. The outstanding performance measured on this system is believed to lead to a drastic price reduction of the RF receiver, compared with an hybrid implementation.