Power-on reset circuit and under-voltage lockout circuit comprising the same
AssigneeSemiconductor Components Industries, LLC
InventorsKinam Song, Wonhi Oh, Jinkyu Choi, BumSeung Jin, Samuell Shin
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Abstract
An UVLO circuit according to an aspect of the present invention includes: a power-on reset (POR) circuit generating an output based on a first current that flows according to an increase of a power supply voltage and not operating in a normal state of the power supply voltage; and a logic operation unit generating a reset signal according to an output of the POR circuit and an output based on a result of comparison between a sense voltage that corresponds to the power supply voltage and a predetermined reference voltage.
Claims19
A power-on reset (POR) circuit comprising:
- a capacitor in which a first current flows according to an increase of a power supply voltage;
- a current mirror configured to mirror the first current to a second current;
- and
- a transistor configured to be operated by the second current,
- wherein the power supply voltage reaches a normal reference voltage, and the POR circuit blocks mirroring of the current mirror and turns off the transistor.
A method, comprising:
- mirroring a first current to a second current;
- charging a capacitor by the first current;
- coupling a first node with a power supply voltage to supply an output current to the first node in response to the second current;
- and
- decoupling the first node from the power supply voltage to stop supplying the output current in a normal state of the power supply voltage.
A power-on reset (POR) circuit comprising:
- a capacitor into which a first current flows according to an increase of a power supply voltage;
- a current mirror configured to mirror the first current to a second current;
- and
- a transistor configured to supply an output current to a node in response to the second current,
- wherein the POR circuit stops supplying the output current in a normal state of the power supply voltage.
Dependencies are inferred from the claim text.