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CN-115955103-B - Voltage selection circuit

CN115955103BCN 115955103 BCN115955103 BCN 115955103BCN-115955103-B

Abstract

Embodiments of the present disclosure provide a voltage selection circuit. The voltage selection circuit includes an input comparison circuit, first and second hysteresis comparators, first and second output control circuits. The input comparison circuit compares magnitudes of the first and second input voltages to generate first and second indication signals. The first hysteresis comparator generates third and fourth indication signals according to the first indication signal. The power supply voltage of the first hysteresis comparator is equal to the first input voltage. The second hysteresis comparator generates fifth and sixth indication signals according to the second indication signal. The power supply voltage of the second hysteresis comparator is equal to the second input voltage. The first output control circuit generates an output voltage according to the first input voltage when the voltages of the third and sixth indication signals are both smaller than the first input voltage. The second output control circuit generates an output voltage according to the second input voltage when the voltages of the fourth and fifth indication signals are both smaller than the second input voltage.

Inventors

  • XUAN ANG

Assignees

  • 圣邦微电子（北京）股份有限公司

Dates

Publication Date
20260512
Application Date
20230117

Claims (10)

  1. 1. A voltage selection circuit comprises an input comparison circuit, a first hysteresis comparator, a second hysteresis comparator, a first output control circuit and a second output control circuit, The input comparison circuit is configured to compare magnitudes of a first input voltage from a first input end and a second input voltage from a second input end to generate a first indication signal and a second indication signal, and provide the first indication signal and the second indication signal to the first hysteresis comparator and the second hysteresis comparator respectively, wherein the first indication signal and the second indication signal are mutually opposite signals; The first hysteresis comparator is configured to generate a third indication signal and a fourth indication signal according to the first indication signal, output the third indication signal from an inverting output terminal of the first hysteresis comparator and output the fourth indication signal from an in-phase output terminal of the first hysteresis comparator, wherein a power supply voltage of the first hysteresis comparator is equal to the first input voltage; Generating a fifth indication signal and a sixth indication signal according to the second indication signal, outputting the fifth indication signal from an inverting output terminal of the second hysteresis comparator and outputting the sixth indication signal from an in-phase output terminal of the second hysteresis comparator, wherein a power supply voltage of the second hysteresis comparator is equal to the second input voltage; The first output control circuit is configured to generate an output voltage from the first input voltage and output the output voltage from a first output terminal of the voltage selection circuit in a case where voltages of the third indication signal and the sixth indication signal are both smaller than the first input voltage; The second output control circuit is configured to generate the output voltage from the second input voltage and output the output voltage from the first output terminal in a case where voltages of the fourth instruction signal and the fifth instruction signal are both smaller than the second input voltage.
  2. 2. The voltage selection circuit of claim 1 wherein the first output control circuit comprises a first transistor and a second transistor, The control electrode of the first transistor is coupled with the inverting output end of the first hysteresis comparator, the first electrode of the first transistor is coupled with the first input end, and the second electrode of the first transistor is coupled with the first electrode of the second transistor; the control electrode of the second transistor is coupled to the non-inverting output end of the second hysteresis comparator, and the second electrode of the second transistor is coupled to the first output end.
  3. 3. The voltage selection circuit of claim 1 wherein the first output control circuit comprises a first transistor and a second transistor, The control electrode of the first transistor is coupled with the in-phase output end of the second hysteresis comparator, the first electrode of the first transistor is coupled with the first input end, and the second electrode of the first transistor is coupled with the first electrode of the second transistor; the control electrode of the second transistor is coupled to the inverting output end of the first hysteresis comparator, and the second electrode of the second transistor is coupled to the first output end.
  4. 4. The voltage selection circuit according to claim 2 or 3, wherein the first output control circuit further comprises a third transistor, and a fourth transistor, Wherein a control electrode of the third transistor is coupled to the control electrode of the first transistor, a first electrode of the third transistor is coupled to the first input terminal, and a second electrode of the third transistor is coupled to a first electrode of the fourth transistor; the control electrode of the fourth transistor is coupled to the control electrode of the second transistor, and the second electrode of the fourth transistor is coupled to the second output end of the voltage selection circuit.
  5. 5. The voltage selection circuit of claim 1 wherein the second output control circuit comprises a fifth transistor and a sixth transistor, The control electrode of the fifth transistor is coupled to the inverting output end of the second hysteresis comparator, the first electrode of the fifth transistor is coupled to the second input end, and the second electrode of the fifth transistor is coupled to the first electrode of the sixth transistor; the control electrode of the sixth transistor is coupled to the non-inverting output terminal of the first hysteresis comparator, and the second electrode of the sixth transistor is coupled to the first output terminal.
  6. 6. The voltage selection circuit of claim 1 wherein the second output control circuit comprises a fifth transistor and a sixth transistor, The control electrode of the fifth transistor is coupled to the non-inverting output end of the first hysteresis comparator, the first electrode of the fifth transistor is coupled to the second input end, and the second electrode of the fifth transistor is coupled to the first electrode of the sixth transistor; The control electrode of the sixth transistor is coupled to the inverting output terminal of the second hysteresis comparator, and the second electrode of the sixth transistor is coupled to the first output terminal.
  7. 7. The voltage selection circuit according to claim 5 or 6, wherein the second output control circuit further comprises a seventh transistor, and an eighth transistor, Wherein a control electrode of the seventh transistor is coupled to the control electrode of the fifth transistor, a first electrode of the seventh transistor is coupled to the second input terminal, and a second electrode of the seventh transistor is coupled to the first electrode of the eighth transistor; the control electrode of the eighth transistor is coupled to the control electrode of the sixth transistor, and the second electrode of the eighth transistor is coupled to the second output terminal of the voltage selection circuit.
  8. 8. A voltage selection circuit includes an input comparison circuit, a first hysteresis comparator, a second hysteresis comparator, a first transistor, a second transistor, a fifth transistor, and a sixth transistor, The input comparison circuit is configured to compare magnitudes of a first input voltage from a first input end and a second input voltage from a second input end to generate a first indication signal and a second indication signal, and provide the first indication signal and the second indication signal to the first hysteresis comparator and the second hysteresis comparator respectively, wherein the first indication signal and the second indication signal are mutually opposite signals; The first hysteresis comparator is configured to generate a third indication signal and a fourth indication signal according to the first indication signal, output the third indication signal from an inverting output terminal of the first hysteresis comparator and output the fourth indication signal from an in-phase output terminal of the first hysteresis comparator, wherein a power supply voltage of the first hysteresis comparator is equal to the first input voltage; Generating a fifth indication signal and a sixth indication signal according to the second indication signal, outputting the fifth indication signal from an inverting output terminal of the second hysteresis comparator and outputting the sixth indication signal from an in-phase output terminal of the second hysteresis comparator, wherein a power supply voltage of the second hysteresis comparator is equal to the second input voltage; The control electrode of the first transistor is coupled with the inverting output end of the first hysteresis comparator, the first electrode of the first transistor is coupled with the first input end, and the second electrode of the first transistor is coupled with the first electrode of the second transistor; The control electrode of the second transistor is coupled with the in-phase output end of the second hysteresis comparator, and the second electrode of the second transistor is coupled with the first output end of the voltage selection circuit; the control electrode of the fifth transistor is coupled to the inverting output end of the second hysteresis comparator, the first electrode of the fifth transistor is coupled to the second input end, and the second electrode of the fifth transistor is coupled to the first electrode of the sixth transistor; the control electrode of the sixth transistor is coupled to the non-inverting output terminal of the first hysteresis comparator, and the second electrode of the sixth transistor is coupled to the first output terminal.
  9. 9. A chip comprising the voltage selection circuit according to any one of claims 1 to 8.
  10. 10. An electronic device comprising a chip according to claim 9.

Description

Voltage selection circuit Technical Field Embodiments of the present disclosure relate to the field of integrated circuit technology, and in particular, to a voltage selection circuit. Background The voltage selection circuit is used for selecting a circuit with higher voltage to supply power for a subsequent system. If the input voltage of the subsequent system is selected from the voltage VIN1 and the voltage VIN2, the subsequent system is powered by VIN1 when VIN1 is higher than VIN2, and the subsequent system is powered by VIN2 when VIN2 is higher than VIN 1. There is a delay in switching between VIN1 and VIN2 to prevent switching back and forth when VIN1 and VIN2 are close, which increases the power consumption of the system. To prevent the through-connection of VIN1 and VIN2 during the switch, there is typically a dead time when VIN1 and VIN2 are switched, during which neither VIN1 nor VIN2 power the system. The dead time is set to avoid the through-connection of VIN1 and VIN2, where no power supply charges the output point during the dead time, so it is desirable that the dead time be as short as possible. Dead time is difficult to control under various process corner and temperature deviations. The system is powered by a large storage capacitor during the dead zone, and the length of the dead zone time can influence the amount of consumed charge, thereby influencing the voltage drop on the storage capacitor, and causing unstable power supply. Disclosure of Invention Embodiments described herein provide a voltage selection circuit, a chip, and an electronic device. According to a first aspect of the present disclosure, a voltage selection circuit is provided. The voltage selection circuit comprises an input comparison circuit, a first hysteresis comparator, a second hysteresis comparator, a first output control circuit and a second output control circuit. The input comparison circuit is configured to compare magnitudes of a first input voltage from a first input terminal and a second input voltage from a second input terminal to generate a first indication signal and a second indication signal, and to provide the first indication signal and the second indication signal to the first hysteresis comparator and the second hysteresis comparator, respectively. Wherein the first indication signal and the second indication signal are mutually opposite signals. The first hysteresis comparator is configured to generate a third indication signal and a fourth indication signal from the first indication signal, to output the third indication signal from an inverting output of the first hysteresis comparator and to output the fourth indication signal from an non-inverting output of the first hysteresis comparator. Wherein the power supply voltage of the first hysteresis comparator is equal to the first input voltage. The second hysteresis comparator is configured to generate a fifth indication signal and a sixth indication signal from the second indication signal, to output the fifth indication signal from an inverting output of the second hysteresis comparator and to output the sixth indication signal from an non-inverting output of the second hysteresis comparator. Wherein the power supply voltage of the second hysteresis comparator is equal to the second input voltage. The first output control circuit is configured to generate an output voltage from the first input voltage and output the output voltage from the first output terminal of the voltage selection circuit in a case where the voltages of the third and sixth indication signals are both smaller than the first input voltage. The second output control circuit is configured to generate an output voltage from the second input voltage and output the output voltage from the first output terminal in a case where the voltages of the fourth and fifth instruction signals are both smaller than the second input voltage. In some embodiments of the present disclosure, the first output control circuit includes a first transistor, and a second transistor. The control electrode of the first transistor is coupled to the inverting output end of the first hysteresis comparator. The first electrode of the first transistor is coupled to the first input terminal. The second pole of the first transistor is coupled to the first pole of the second transistor. The control electrode of the second transistor is coupled to the non-inverting output terminal of the second hysteresis comparator. The second electrode of the second transistor is coupled to the first output terminal. In some embodiments of the present disclosure, the first output control circuit includes a first transistor, and a second transistor. The control electrode of the first transistor is coupled to the in-phase output end of the second hysteresis comparator. The first electrode of the first transistor is coupled to the first input terminal. The second pole of the first transistor is coupled to the first pole of th