EC464 Low Power VLSI

The threshold voltage

• Increases on increasing temperature

• Decreases on increasing temperature

• Does not depend on temperature

• May increases or decrease with increasing temperature depending upon other factors

Weak inversion occurs when gate voltage is

• Less than 0

• Greater than 0 but less than threshold voltage

• Equal to 0

• Greater than threshold

The SI unit of body effect parameter is

• V

• V²

• √V

• No unit

When channel width decreases, the threshold voltage

• Decreases

• Increases

• Remains the same

• changes the polarity

The situation in which gate voltage has no control over the drain current occurs in

• Narrow width effect

• Velocity saturation

• DIBL

• GIDL

At ------------------- the drain current is no longer related to the Vgs by square law relationship

• high temperature

• low temperature

• Velocity saturation

• None of these

An NMOS transistor has Vt0= 0.8V, 2ФF= 0.7V, γ=0.4√V , V_SB= 3V. Find Vt

• 1.55V

• 1.89V

• 1.12V

• 1.23V

Strong inversion occurs when

• Surface potential is equal to Fermi level

• Surface potential is equal to 0

• Surface potential is negative

• Surface potential is positive and equal to twice the Fermi level

The condition when the depletion region of drain and source merge occurs in

• Velocity saturation

• Hot electron effect

• Narrow width effect

• Punch through

The threshold voltage will be decreased when

• Channel length is decreased

• Channel width is decreased

• channel width is increased

• Both a and b

• Both a and c