Output circuit having multi-level output and comparator circuit therof
AssigneeSigmastar Technology Ltd.
InventorsHao Wang, Zhen-Yang Pang
Life of this patent
Estimating the term…
Abstract
An output circuit includes a comparator circuit, a voltage conversion circuit and a signal output circuit. The comparator circuit detects an operating mode based on a first supply voltage and a second supply voltage and generates a first control signal. The voltage conversion circuit adjusts a level of an output voltage from a low-dropout regulator according to the first control signal to generate a first voltage, and generates a second voltage according to the first control signal and the first voltage. The signal output circuit adjusts a level of a digital signal according to the first voltage, the second voltage and the first supply voltage to generate a digital output signal corresponding to the operating mode.
Claims15
An output circuit, comprising:
- a comparator circuit, detecting an operating mode based on a first supply voltage and a second supply voltage and generating a first control signal;
- a voltage conversion circuit, adjusting a level of an output voltage from a low-dropout regulator according to the first control signal to generate a first voltage, and generating a second voltage according to the first control signal and the first voltage;
- and
- a signal output circuit, adjusting a level of a digital signal according to the first voltage, the second voltage and the first supply voltage to generate a digital output signal corresponding to the operating mode.
A comparator circuit, detecting an operating mode according to a first supply voltage and a second supply voltage, the comparator circuit comprising:
- a filter circuit;
- a second transistor, receiving the second supply voltage through the filter circuit, and selectively turned on according to a level of a control node so as to transmit the second supply voltage to a first node;
- a comparator, comparing a level of the first node with a predetermined voltage to generate a first signal, wherein the predetermined voltage is generated by dividing the first supply voltage;
- a first transistor, selectively turned on according to the first signal so as to output the first supply voltage as a first control signal;
- and
- a pull-down resistor, coupled between the first transistor and a ground.
An output circuit, comprising:
- a voltage conversion circuit, adjusting a level of an output voltage from a low-dropout regulator according to a first control signal to generate a first voltage, and generates a second voltage according to the first control signal and the first voltage;
- a level adjustment circuit, adjusting a level of a digital signal according to the first voltage, the second voltage, a first bias voltage, a second bias voltage and the first supply voltage so as to generate a digital output signal;
- and
- a plurality of control circuits, outputting, between the digital output signal and the second voltage, the one having a lower level as the second bias voltage, and outputting, between the digital output signal and the first voltage, the one having a higher level as the first bias voltage.
Dependencies are inferred from the claim text.