Level shift circuit

Abstract

In a level shift circuit according to the invention, either an input signal IN or an inverted input signal XIN, which are input into the gate electrodes of n-type transistors 1, 2 for signal input, is also given to the substrate of that n-type transistor via p-type transistors 5, 6 for substrate bias. When the signal IN or XIN rises and changes, the threshold voltages of the n-type transistors 1, 2 for signal input is lowered due to the substrate bias effect. Consequently, even if the signal IN or XIN has a low voltage level, operation is carried out at high speeds. Also, when either an output signal OUT or an inverted output signal XOUT is changed to a high voltage level, the transistors 5, 6 for substrate bias become non-conducting, and thus the input signal IN or the inverted input signal XIN is not supplied to the substrate of the n-type transistors 1, 2 for signal input other than when the signal is changing. Consequently, a constant passing-through current does not flow to the substrate of these transistors.

Description

technical field [0001] The present invention relates to level shifting circuits for interfacing between circuits having different supply voltages. Background technique [0002] With recent refinement of manufacturing, the power supply voltage of the internal circuits of semiconductor integrated circuits tends to be lowered due to the reliability of components. On the other hand, among the components used in systems such as electronic equipment, there are some components that continue to use the conventional power supply voltage. In order to achieve connection between these elements having different power supply voltages and the semiconductor integrated circuit, a level shift circuit is generally built in the semiconductor integrated circuit. [0003] Recently, even in semiconductor integrated circuits, in order to reduce power consumption, measures have been taken to supply optimal power supply voltages to each circuit block, and in order to obtain the connection between th...

AI Technical Summary

Problems solved by technology

As a result, in the process of changing these signals IN and XIN from 0V to a specified voltage level (0.7V), the operation of the N-channel transistors 1 and 2 that switch to the conduction state is slow, resulting in a level shift circuit Overall movement speed deteriorates

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