Comparator having a reduced number of elements

A comparator circuit adapted for receiving a potential, the comparator circuit comprising:

• a first transistor, of a first conductivity type, including
• a first end having at least one terminal,
• a second end having at least one terminal, and
• a first control terminal for controlling a current flow between the first and second ends;
• a second transistor of a second conductivity type, including
• a first end having at least one terminal, the first end being coupled to the first control terminal,
• a second end having at least one terminal, the second end being coupled to the potential, and
• a second control terminal for controlling a current flow between the first and second ends, the second control terminal being coupled to the first end of the first transistor;
• a first resistance element coupled between the second control terminal and the potential;
• a second resistance element coupled between the first control terminal and the potential;
• and
• a third transistor of the second conductivity type, including a third control terminal coupled to the first end of the second current path.

A comparator circuit adapted for receiving a potential, the comparator circuit comprising:

• a first transistor, of a first conductivity type, including
• a first end having at least one terminal,
• a second end having at least one terminal, and
• a first control terminal for controlling a current flow between the first and second ends;
• a second transistor of a second conductivity type, including
• a first end having at least one terminal, the first end being coupled to the first control terminal,
• a second end having at least one terminal, the second end being coupled to the potential, and
• a second control terminal for controlling a current flow between the first and second ends, the second control terminal being coupled to the first end of the first transistor;
• a first resistance element coupled between the second control terminal and the potential;
• a second resistance element coupled between the first control terminal and the potential;
• a third resistance element coupled between another potential and the first control terminal;
• a third transistor of the second conductivity type, including a third control terminal coupled to the first end of the second current path;
• a fourth transistor including
• a first end having at least one terminal, the first end being coupled to the second end of said first transistor,
• a second end having at least one terminal, the second end being coupled to the potential, and
• a fourth control terminal for controlling a current flow between the first and second ends, the control terminal being coupled to the first end of the first transistor;
• a capacitor coupled in parallel with the first and second ends of said fourth transistor;
• and
• a fourth resistance element coupled between the second end of said first transistor and another potential.

A comparator circuit with a hysteresis, the comparator circuit being adapted for receiving a first potential and a second potential, the comparator circuit comprising:

• a first transistor of a first conductivity type, including
• a first collector means,
• a first emitter means, and
• a first base;
• a second transistor of a second conductivity type, including
• a second collector means,
• a second emitter means, and
• a second base, the first collector means being coupled to the second base and the second collector means being coupled to the first base between the first potential and the second potential so as to provide positive feedback;
• a first resistance element coupled between the second base and the second potential;
• a second resistance element in a positive feedback path between the first base and the second collector means;
• and
• a third transistor of the second conductivity type having a third base coupled to the second collector means.

A comparator circuit adapted for receiving a potential, the comparator circuit comprising:

• a first transistor, of a first conductivity type, including
• a first collector means,
• a first emitter means, the first collector means and first emitter means defining a first current path, and
• a first base;
• a second transistor of a second conductivity type, including
• a second collector means coupled to the first base,
• a second emitter means coupled to the potential, the second collector means and second emitter means defining a second current path coupled between the first base and the second potential, and
• a second base coupled to the first collector means;
• a first resistance element coupled between the second base and the potential;
• a second resistance element coupled between the first base and the potential;
• and
• a third transistor of the second conductivity type, including a third emitter means coupled to the second potential, and a third base coupled to the second current path.

A comparator circuit adapted for receiving a potential, the comparator circuit comprising:

• a first transistor, of a first conductivity type, including
• a first collector means,
• a first emitter means, the first collector means and first emitter means defining a first current path, and
• a first base;
• a second transistor of a second conductivity type, including
• a second collector means coupled to the first base,
• a second emitter means coupled to the potential, the second collector means and second emitter means defining a second current path coupled between the first base and the second potential, and
• a second base, coupled to the first collector means;
• a first resistance element coupled between the second base and the potential;
• a second resistance element coupled between the first base and the potential;
• a third resistance element coupled between another potential and the first base;
• a third transistor of the second conductivity type, including a third collector means, a third emitter means, the third collector means and a third emitter means defining a third current path, and third base coupled to the second current path;
• a fourth transistor including
• a fourth collector means, the collector means being coupled to the emitter means of the first transistor,
• a fourth emitter means, the emitter means being coupled to the potential, the fourth collector means and fourth emitter means defining a fourth current path coupled between first emitter means and the second potential, and
• a fourth base, the base being coupled to the first collector means;
• a capacitor coupled in parallel with the fourth current path;
• and
• a fourth resistance element coupled between the first emitter means and the first potential.