Multi-threshold CMOS utilized transistor

Transistor

A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...

s with multiple threshold voltage

Voltage

Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...

s (Vt) to optimize delay or power. Lower voltage devices are used on critical delay paths to minimize clock periods. Higher voltage devices are used on non-critical paths to reduce static leakage power without incurring a delay penalty. Typical high voltage devices reduce static leakage by 10 times compared with low voltage devices. One method of creating devices with multiple threshold voltages is to apply different bias voltages (Vb) to the base or bulk terminal of transistors, the other way can be "gate engineering". In MOSFET

MOSFET

The metal–oxide–semiconductor field-effect transistor is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925...

 devices, lower bias voltages will increase voltages, increase delay, and reduce static leakage.

A common MTCMOS approach for reducing power

Electric power

Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...

 uses sleep transistors. Logic is supplied by a virtual power rail. Low voltage devices are used in the logic for speed. The logic may be turned off by collapsing the virtual power rail. High voltage devices connecting the power rails and virtual power rails are turned off in sleep mode

Sleep mode

Sleep mode refers to a low power mode for electronic devices such as computers, televisions, and remote controlled devices. These modes save significant electrical consumption compared to leaving a device fully on and idle, but allow the user to avoid having to reset programming codes or wait for a...

. High voltage devices are used as sleep transistors to reduce static leakage.

The design of the power switch

Switch

In electronics, a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another....

 which turns on and off the power supply

Power supply

A power supply is a device that supplies electrical energy to one or more electric loads. The term is most commonly applied to devices that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy to electrical energy...

 to the logic gate

Logic gate

A logic gate is an idealized or physical device implementing a Boolean function, that is, it performs a logical operation on one or more logic inputs and produces a single logic output. Depending on the context, the term may refer to an ideal logic gate, one that has for instance zero rise time and...

s is essential to low-voltage high-speed circuit

Electrical network

An electrical network is an interconnection of electrical elements such as resistors, inductors, capacitors, transmission lines, voltage sources, current sources and switches. An electrical circuit is a special type of network, one that has a closed loop giving a return path for the current...

techniques such as multi-threshold voltage CMOS (MTCMOS). This is because this switch influences the speed, area, and power of a low-voltage LSI.