Level shifter
AssigneeVIA Technologies, Inc.
InventorChao-Sheng Huang
Life of this patent
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Abstract
A level shifter for shifting an input signal to an output signal. The level shifter includes an input buffer biased a first voltage and a ground voltage; an output buffer and a level-processing unit both biased between a second voltage and the ground voltage; and a voltage-drop unit coupled to the level-processing unit and biased between the first voltage and the second voltage. While the first voltage is in an OFF state and the second voltage is switched on, the voltage-drop unit provides an initializing voltage for the level-processing unit according to the second voltage to shift the input signal to provide the output signal.
Claims9
A level shifter for generating an output signal from an input signal comprising:
- an input buffer biased with both a first voltage and a ground voltage and receiving the input signal, wherein the input buffer has a first output end and a second output end;
- an output buffer biased with both a second voltage and the ground voltage and outputting the output signal;
- a level-processing unit coupled between the output buffer and the input buffer via the first output end and the second output end, wherein the level-processing unit is biased with both the second voltage and the ground voltage for shifting the input signal to provide the output signal;
- and
- a voltage-drop unit coupled to the level-processing unit, biased with both the first voltage and the second voltage, and providing an initializing voltage for the level-processing unit according to the second voltage while the first voltage source is in an OFF and the second voltage is switched on;
- wherein the voltage-drop unit comprises:
- a voltage-drop element coupled to the second voltage for providing a voltage drop of the second voltage;
- and
- a switching element coupled to the voltage-drop element in series, wherein the switching element is conducted in response to the OFF state of the first voltage and provides the initializing voltage for the level-processing unit.
Dependencies are inferred from the claim text.