Current comparator

A current comparator, comprising:

• a first inverting amplifier that comprises,
• first and second input terminals,
• an output terminal,
• a reference current source that supplies a reference current to the first input terminal,
• a load circuit that supplies a first current to the output terminal, wherein the load circuit is coupled to the first input terminal and the first current is substantially equal to the reference current,
• a driving circuit that generates an output voltage having a prescribed level by controlling the first current according to an input current applied to the second input terminal, and
• a circuit coupled between a control terminal of the driving circuit and the output terminal;
• and
• a second inverting amplifier that comprises,
• a pull-up transistor, and
• a pull-down transistor, wherein the pull-up transistor and the pull-down transistor are coupled in series between first and second prescribed voltages, wherein the pull-up transistor is controlled by the reference current, and wherein the pull-down transistor is controlled by the output voltage at the output terminal of the first inverting amplifier.

A comparator, comprising:

• first and second input terminals;
• an output terminal;
• a reference current source that supplies a reference current to the first input terminal;
• an input current source that supplies an input current to the second input terminal;
• a resistive circuit coupled between the first input terminal, the second input terminal and the output terminal that provides an output voltage to the output terminal according to the input current and the reference current, and
• an inverting amplifier that comprises,
• a pull-up transistor, and
• a pull-down transistor, wherein the pull-up transistor and the pull-down transistor are coupled in series between first and second prescribed voltages, and wherein the pull-up transistor is controlled by the reference current, and wherein the pull-down transistor is controlled by the output voltage at the output terminal.

A current comparator, comprising:

• first and second input terminals;
• an output terminal;
• a reference current source that supplies a reference current to the first input terminal;
• a first transistor and a second transistor having control electrodes coupled together and first electrodes coupled to a first prescribed voltage, wherein a second electrode of the first transistor is coupled to the control electrode of the second transistor and the first input terminal, wherein the second electrode of the second transistor is coupled to the output terminal, wherein the second transistor supplies a first current to the output terminal, and wherein the first current is substantially equal to the reference current;
• a third transistor having a first electrode coupled to a second prescribed voltage, a control electrode coupled to the second input terminal and a second electrode coupled to the output terminal, wherein the third transistor generates an output voltage by controlling the first current according to an input current applied to the second input terminal;
• and
• a fourth transistor having a control electrode coupled to an enabling voltage, a first electrode of the fourth transistor is coupled to a control electrode of the third transistor and the second input terminal, and a second electrode of the fourth transistor is coupled to the output terminal.

A current comparator, comprising:

• first and second input terminals;
• an output terminal;
• a reference current source that supplies a reference current to the first input terminal;
• a load circuit that supplies a first current to the output terminal, wherein the load circuit is coupled between the first input terminal and the output terminal;
• a driving circuit coupled between the second input terminal and the output terminal that generates an output voltage by controlling the first current according to an input current applied to the second input terminal;
• and
• a first transistor coupled between the driving circuit and the output terminal, wherein the first transistor has a control electrode coupled to receive a first prescribed voltage, wherein the first transistor is coupled between an electrode of a transistor in the load circuit and a control terminal of the driving circuit.