Full-swing Schottky BiCMOS/BiNMOS and the effects of operatingfrequency and supply voltage scaling

Novel full-swing BiCMOS/BiNMOS logic circuits which use Schottky diode in the pull-up section for low supply-voltage regime are developed. The full-swing pull-up operation is performed by saturating the bipolar transistor with a base current pulse. After which, the base is isolated and bootstrapped to a voltage higher than V_DD. The BiCMOS/BiNMOS circuits do not require a PNP bipolar transistor. They outperform other BiCMOS circuits at low supply voltage, particularly at 2 V using 0.5 μm BiCMOS technology. Delay, area, and power dissipation comparisons have been performed. The new circuits offer delay reduction at 2 V supply voltage of 37% to 56% over CMOS. The minimum fanout at which the new circuits outperform CMOS gate is 2 to 3. Furthermore, the effect of the operating frequency on the delay of a wide range of BiCMOS and BiNMOS circuits is reported for the first time, showing the superiority of the Schottky circuits