Table of Contents

## What is KN and KP in CMOS?

For the same dimensions of NMOS and PMOS transistors (complementary MOS transistors) propagation delay time in the CMOS inverter are asymmetrical tPLH > tPHL (because kn>kp). While, for symmetrical (matching) conditions (kn= kp), the propagation delay times in the CMOS inverter are equal (tPHL = tPLH).

## What is KR in CMOS inverter?

Influence of MOS transistor transconductance parameters ratio (kr) on output voltage value Vo, when the input terminal of CMOS inverter is biased by voltage Vin = VIL, for several parametric values of complementary MOS transistor threshold voltage.

## What is the value of current when a CMOS inverter is idling in any of the logic state?

� no current while idling in any logic state. Since usually Lp � Ln ⇒ Wp � 2Wn.

## How can I speed up my CMOS inverter?

It is possible to speed-up the inverter by reducing the width of the PMOS device (at the expense of symmetry and noise margins)! by causing a larger parasitic capacitance. This implies that there is an optimal ratio that balances the two contradictory effects. Consider two identically sized CMOS inverters.

## How is inverter threshold voltage calculated?

Vth is the inverter threshold voltage, which is Vdd /2, where Vdd is the output voltage. The output is switched from 0 to Vdd when input is less than Vth. So, for 0

## What is the delay of an inverter?

The propagation delay of a logic gate e.g. inverter is the difference in time (calculated at 50% of input-output transition), when output switches, after application of input.

## What is a CMOS inverter?

CMOS inverters (Complementary NOSFET Inverters) are some of the most widely used and adaptable MOSFET inverters used in chip design. They operate with very little power loss and at relatively high speed. Furthermore, the CMOS inverter has good logic buffer characteristics, in that, its noise margins in both low and high states are large.

## What is the maximum current dissipation for CMOS inverter?

the maximum current dissipation for our CMOS inverter is less than 130uA. Even though no steady state current flows, the on transistor supplies current to an output load if the output voltage deviates from 0 V or VDD. This makes CMOS technology useable in low power and high-density applications.

## Does inverter analysis apply to the NAND gate?

The same is true for the NAND gate. The same transfer characteristic method is used for these two gates. With the appropriate changes to k n and k p in the MOSFET drain current equations, the inverter analysis still applies.

## What does the output voltage curve of a CMOS circuit represent?

The curve represents the output voltage taken from node 3. You can easily see that the CMOS circuit functions as an inverter by noting that when VIN is five volts, VOUT is zero, and vice versa. Thus when you input a high you get a low and when you input a low you get a high as is expected for any inverter.