Trigger comparator circuit

Claim 2

A trigger comparator for sensing voltage level variations in a voltage source, said comparator comprising: a. an operational amplifier having a first differential input terminal, a second differential input terminal, and an output terminal; b. a voltage divider means having a first and second outer terminal for connection to the voltage source, a first tap terminal and the second outer terminal defining a first tapped portion, and a second tap terminal and the second outer terminal defining a second tapped portion, the second tapped portion being greater in resistance than the first tapped portion; c. means for connecting the second differential input terminal of the operational amplifier to the second tap terminal; d. means for connecting the first differential input terminal of the operational amplifier to a source of reference voltage; e. switch means, having a first switch terminal connected to the first tap terminal, a switch control terminal connected to the output terminal of the operational amplifier; and a second switch terminal for connection to a source of working voltage; whereby in response to an increase in the voltage magnitude at the voltage source the switch means establishes a connection between the first and second tap terminals to channel current supplied by the source of working voltage through the first tapped portion of the voltage divider thereby increasing the voltage magnitude at the second tap terminal and holding the switch means in its conducting state until a decrease in voltage magnitude at the voltage source.

Claim 3

A trigger comparator for sensing voltage level variations from a normal voltage level at a voltage source, said comparator comprising: a. an operational amplifier having a first differential input terminal, a second differential input terminal and an output terminal; b. a first voltage divider means, the first voltage divider means having first, second and third resistance means serially connected and arranged for connection across the voltage source, the junction of the first and second resistance means defining a first divider tap terminal, and the junction of the second and third resistance means defining a second divider tap terminal; c. means for connecting the first differential input terminal of the operational amplifier to a source of reference voltage; d. means for connecting the second differential input terminal of the operational amplifier to the second divider tap termianl; e. switch means, having a switch control terminal connected to the output terminal of the operational amplifier, a first switch terminal connected to the first divider tap terminal, and a second switch terminal for connection to a source of working voltage; whereby in response to an increase in the voltage level at the voltage source, a corresponding voltage level increase Appears at the output terminal of the operational amplifier to turn ''''ON'''' the switch means and to channel current supplied by the source of working voltage through the first divider tap terminal, thereby changing the potential at the second divider tap terminal to support said increase in voltage level in locking the switch means ''''ON'''' until the voltage level at the voltage source returns to normal.

Claim 4

A trigger comparator for sensing voltage level variations from a normal voltage level at a voltage source, said comparator comprising: a. an operational amplifier having a first differential input terminal, a second differential input terminal and an output terminal; b. a first voltage divider means, the first voltage divider means having first, second and third resistance means serially connected and arranged for connection across the voltage source, the junction of the first and second resistance means defining a first divider tap terminal, and the junction of the second and third resistance means defining a second divider tap terminal; c. means for connecting the first differential input terminal of the operational amplifier to a source of reference voltage; d. means for connecting the second differential input terminal of the operational amplifier to the second divider tap termianl; e. switch means, having a switch control terminal connected to the output terminal of the operational amplifier, a first switch terminal connected to the first divider tap terminal, and a second switch terminal for connection to a source of working voltage; whereby in response to an increase in the voltage level at the voltage source, a corresponding voltage level increase Appears at the output terminal of the operational amplifier to turn ''''ON'''' the switch means and to channel current supplied by the source of working voltage through the first divider tap terminal, thereby changing the potential at the second divider tap terminal to support said increase in voltage level in locking the switch means ''''ON'''' until the voltage level at the voltage source returns to normal.

Claim 5

A trigger comparator for sensing variations in the voltage level of a voltage source, said comparator comprising: a. an operational amplifier having an inverting input terminal, a non-inverting input terminal and an output terminal; b. a first voltage divider means having first, second and third resistors serially connected and arranged for connection across the voltage source, the junction of the second and third resistors being connected to the non-inverting input terminal of the operational amplifier; c. means for connecting the inverting input terminal of the operational amplifier to a source of reference voltage; d. a transistor switch, the base of said switch being connected to the output terminal of the operational amplifier, the emitter of said switch being connected to the junction of the first and second resistors and the collector of said switch arranged for connection to a source of working voltage; whereby in response to an increase in the voltage level at the voltage source, a corresponding voltage level increase at the output terminal of the operational amplifier turns ''''ON'''' the transistor switch and channels current supplied by the source of working voltage to the junction of the first and second resistors thereby raising the voltage level at the non-inverting input terminal of the operational amplifier so as to lock the transistor switch ''''ON'''' until a decrease in voltage level at the voltage source.

Claim 6

A trigger comparator for sensing variations in the voltage level of a voltage source, said comparator comprising: a. an operational amplifier having an inverting input terminal, a non-inverting input terminal and an output terminal; b. a first voltage divider means having first, second and third resistors serially connected and arranged for connection across the voltage source, the junction of the second and third resistors being connected to the non-inverting input terminal of the operational amplifier; c. means for connecting the inverting input terminal of the operational amplifier to a source of reference voltage; d. a transistor switch, the base of said switch being connected to the output terminal of the operational amplifier, the emitter of said switch being connected to the junction of the first and second resistors and the collector of said switch arranged for connection to a source of working voltage; whereby in response to an increase in the voltage level at the voltage source, a corresponding voltage level increase at the output terminal of the operational amplifier turns ''''ON'''' the transistor switch and channels current supplied by the source of working voltage to the junction of the first and second resistors thereby raising the voltage level at the non-inverting input terminal of the operational amplifier so as to lock the transistor switch ''''ON'''' until a decrease in voltage level at the voltage source.

Claim 7

The invention as defined in claim 3 wherein the emitter of the transistor switch is connected to the junction of the first and second resistors through a first bias diode poled in the same direction as the emitter base junction of said transistor switch.

Claim 8

The invention as claimed in claim 3 further comprising a fourth and fifth resistor serially connected and arranged to form a second voltage divider between the output terminal of the operational amplifier and the voltage source at the first resistor, the base of the transistor switch being connected to the junction of the fourth and fifth resistors.

Claim 9

The invention as claimed in claim 4 further comprising a fourth and fifth resistor serially connected and arranged to form a second voltage divider between the output terminal of the operational amplifier and the voltage source at the first resistor, the base of the transistor switch being connected to the junction of the fourth and fifth resistors.

Claim 10

The invention as defined in claim 4 further comprising means to forward bias the first bias diode.

Claim 11

The invention as defined in claim 7 wherein the means to forward bias the first bias diode comprises a sixth resistor having one end connected to the emitter of the transistor switch and the other end arranged for connection to a source of bias voltage.

Claim 12

The invention as defined in claim 4 wherein the transistor switch includes an npn transistor and the emitter of said transistor is connected to the anode of said diode.

Claim 13

The invention as defined in claim 4 wherein the transistor switch includes a pnp transistor and the emitter of said transistor is connected to the cathode of said diode.

Claim 14

The invention as defined in claim 3 wherein the voltage source, the reference voltage and the source of working voltage have a common terminal connected to the first resistor.

Claim 15

The invention as defined in claim 8 wherein the voltage source, the reference voltage, the source of working voltage and the source of bias voltage have a common terminal connected to the first resistor.

Claim 16

The invention as defined in claim 6 further comprisIng: a. a seventh and eighth resistor serially connected and arranged to form a third voltage divider between the output terminal of the operational amplifier and the voltage source at the first resistor; b. an output transistor, having its base connected to the junction of the seventh and eighth resistors and its collector arranged for connection to a source of output current, c. a second bias diode, poled in the same direction as the emitter base junction of the output transistor, connecting the emitter of the output transistor to the voltage source at the first resistor, d. a ninth resistor having one end connected to the emitter of the output transistor and the other end arranged for connection to the source of working voltage.