Standard Digital CMOS Design-1
Standard Cell This project would involve some standard cells of cmos digital circuit. Some basic logic circuit can be made by using these standard cells. 1.1 Inverter Inverter is a very basic stand cell, which output is opposite of input voltage. Fig. 1.1 is the symbol of inverter. In this symbol, the vdd is voltage supply, gnd is ground, vin is input voltage, and vout is the output voltage. Figure 1.1 Symbol of Inverter Fig 1.2 is the cmos digital circuit of inverter, because the transmit speed of Pmos is faster than Nmos, so the width of Pmos should be 2 to 3 times bigger than width of Nmos. In Fig. 2, the width of Pmos is 320 nm, and the Nmos is 160 nm. In this library, there is a “subc” parameter which is essential in every Nmos, which can help the base of Nmos connect to the ground. Figure 1.2 CMOS circuit of Inverter Fig 1.3 is Noise of inverter, the noise is obviously in low frequency, the reason is the size of cmos gate is very small, therefore, the leak voltage ...
