Question

(i) Consider a CMOS inverter supplied at V_DD= 5V with transistor parameters of K_N=K_P=50µA/V² and V_TN=-V_TP=1V. Then consider another CMOS inverter supplied at V_DD= 10V with the same transistor parameters. Draw the VTC of both inverters showing all regions of operation and the middle voltage VM. Verify your results using PSpice.

            (ii) Draw the square root of the CMOS inverter current versus the input voltage for the two CMOS inverters in given in part (i) biased at either V_DD=5 V or V_DD=10 V. Determine the peak current of the CMOS inverter at V_DD=5 V & V_DD=10 V. Verify your results using PSpice.

part(ii) required

PSpice for both parts

Answer 1

Part i)

5V SUPPLY:

VOL:

eq1

In eq1

VIL:

eq 2

In eq2

VM, transistors have the same mobility, thus:

10V SUPPLY:

VIH

eq1

VIL

eq 2

VM:

	VDD=5V	VDD=10V
VOL	0V	0V
VOH	5V	10V
VIH	2.54V	6V
VIL	1.45V	3.44V
VM	2.5V	5V