NMOS FET Logic
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
The reduction of the power supply voltage and the voltage swing significantly improves the power delay product of a logic circuit by means of an additional converter. This leads to an improvement of the design of high-density NMOS FET chips. One of the major problems in the design of VLSI logic chips is power dissipation. The input up-level VIN(UP) applied to a conventional logic block, for example, inverter T5, T6, should be at least VIN'(UP) / VTmax + VODR where VTmax is the maximum threshold voltage of T6 (N 1.5 V) and VODR is the overdrive voltage VGS - VT depending upon the required logic block delay (N N 1.5 V). Therefore, the inverter must be connected to a power supply voltage VL of not less than 3 ... 5 V for generating an output up-level (at T6), guaranteeing that the next logic stage is reliably turned on.