Current mode digital gates for mixed mode reprogrammable integrated system

This paper presents some aspects of building a reprogrammable system using current mode gates. With this approach it is possible to extend system on a chip solutions into the area of mixed mode applications. CMOS current mode gates consume almost constant current from the power supply and therefore are suitable for mixed mode operations. Contrary to voltage mode digital gates, presented in the paper current mode gates do not produce strong voltage and current fluctuations in the common substrate of the SoC. The paper shows three generations of current mode gates and describes, in which way static noise margins were achieved in this technique, from the basic concept to the advanced design. Results of PSPICE simulations, based on BSIM3v3 models, are presented as well as a report of ASIC chip tests.